# GCN_circulars

GRB_name: GRB080319B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7484
SUBJECT: GRB 080319B optical observations
DATE:    08/03/20 13:57:38 GMT
FROM:    AAVSO GRB Network at AAVSO  <matthewt@aavso.org>

Veli-Pekka Hentunen (Varkaus, Finland), Arto Oksanen (Muurame, Finland),
and Petri Kehusmaa (Hyvinkaa, Finland) report to the AAVSO High Energy
Network the following optical detections and upper limits of GRB 080319B
(Racusin et al., GCN Circular #7427):

Veli-Pekka Hentunen and Markku Nissinen (Taurus Hill Obs., Varkaus,
Finland) report the detection of the optical afterglow of GRB 080319B
(Racusin et al., GCN Circular #7427).  The afterglow was observed
unfiltered for a total of 1500 seconds using an SBIG ST8-XME CCD mounted
on a Meade LX200 0.3-m telescope.  Observations commenced approximately
15.3 hours post-burst; the mid-point of the observations was 2008 March
19.8999 UT. The afterglow was clearly detected at an unfiltered
magnitude of 19.08 +/- 0.02, calibrated relative to USNO-A2.0
1200-07324239.

A detailed report of this observation is available at the following URL:
ftp://ftp.aavso.org/grb/Veli-PekkaHentunen_080319B_2454545.53358_.txt

A FITS image of this observation is available at the following URL:
ftp://ftp.aavso.org/grb/Veli-PekkaHentunen_080319B_2454545.53358_.fits


Petri Kehusmaa (Slope Rock Observatory, Hyvinkaa, Finland) reports a
non-detection of the optical afterglow of GRB 080319B.  The afterglow
was observed through a V filter for a total of 1800 seconds using an
SBIG ST-7XME CCD mounted on a 0.2-m telescope.  Observations commenced
approximately 17 hours post-burst; the mid-point of the observations was
2008 March 19.9675 UT.  The afterglow was not detected in the V-band
with an upper limit of R=17.6 (calibrated relative to USNO-A2.0).

A detailed report of this observation is available at the following URL:
ftp://ftp.aavso.org/grb/PetriKehusmaa_GRB080319B_2454545.93778_.txt

A FITS image of this observation is available at the following URL:
ftp://ftp.aavso.org/grb/PetriKehusmaa_GRB080319B_2454545.93778_.fits

Arto Oksanen and Olli-Pekka Reimaala (Hankasalmi Obs., Hankasalmi,
Finland) also report the detection of the optical afterglow of GRB
080319B.  The afterglow was observed unfiltered for a total of 2040
seconds (17 x 120s) using an SBIG STL-1001E CCD mounted on an RC Optical
Systems 0.4-m telescope. Observations commenced approximately 19.3 hours
post-burst; the mid-point of the observations was 2008 March 20.0639 UT.
The afterglow was clearly detected at an unfiltered (CR) magnitude 19.0
+/- 0.1, calibrated relative to USNO-A2.0. Note that this magnitude uses
a different comparison star from that of Hentunen and Nissinen (see
above), and may be offset by a few tenths of a magnitude.

A detailed report of this observation is available at the following URL:
ftp://ftp.aavso.org/grb/ArtoOksanen_GRB080319B_2454545.72325_.txt

A FITS image of this observation is available at the following URL:
ftp://ftp.aavso.org/grb/ArtoOksanen_GRB080319B_2454545.72325_.fits

The AAVSO thanks the Curry Foundation for their continued support of the
AAVSO International High Energy Network.


GRB_name: GRB080319B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7485
SUBJECT: GRB 080319B: Allen Telescope Array Observations
DATE:    08/03/20 14:16:39 GMT
FROM:    Josh Bloom at UC Berkeley  <jbloom@astron.berkeley.edu>

Garrett Keating, Geoffrey Bower, Rick Forster, and J. S. Bloom (UC  
Berkeley) report for the Allen Telescope Array team:

"The Allen Telescope Array observed GRB 080319B (Racusin et al.; GCN  
7247) at a frequency of 1.43 GHz.  Observations were obtained on 20  
March 2008 between 5 and 7 UT. From this initial dataset, we report a  
non-detection at the location of afterglow with a 3 sigma upper limit  
of 18 mJy.  Observations are continuing."

This message may be cited.


GRB_name: GRB080319B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7486
SUBJECT: GRB 080319B: Gemini-South photometry
DATE:    08/03/20 14:26:36 GMT
FROM:    Daniel Perley at U.C. Berkeley  <dperley@astro.berkeley.edu>

D. A. Perley, J. S. Bloom (UC Berkeley) and H.-W. Chen (U Chicago) report:

On the night of 2008-03-20 (UT) we observed the optical afterglow of GRB 
080319B (GCN 7427, Racusin et al.) with Gemini-South + GMOS in g, r, i, 
and z filters (4x180s in each filter).  The source is well-detected in 
all bands.  Magnitudes, calibrated to SDSS DR6, are:

UTstart  UTend    t(hr)  filt mag   err
06:52:17 07:10:19 24.808  g   20.95 0.09
07:11:19 07:26:11 25.099  r   20.55 0.03
07:27:10 07:42:04 25.363  i   20.40 0.05
07:43:04 07:57:55 25.686  z   20.32 0.03

We thank the observing staff for performing these observations.


GRB_name: GRB080319C
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7487
SUBJECT: Konus-Wind observation of GRB 080319C
DATE:    08/03/20 14:34:46 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val@mail.ioffe.ru>

S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks,
and T. Cline on behalf of the Konus-Wind team report:

The long GRB 080319C (Swift-BAT trigger #306778: Pagani et al., GCN
7442, Stamatikos et al., GCN 7483)
triggered Konus-Wind at T0=44757.938 s UT (12:25:57.938).

The burst light curve shows a multipeaked structure
with a total duration of ~15 s.

As observed by Konus-Wind the burst
had a fluence of 1.50(-0.21, +0.34)x10^-5 erg/cm2,
and a 256-ms peak flux measured from T0+0.256 s
of 3.35(-0.70, +0.79)x10^-6 erg/cm2/s
(both in the 20 keV - 4 MeV energy range).

The time-integrated spectrum of the burst
(from T0 to T0+16.640 s) is well fitted (in the 20 keV-4 MeV range)
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with alpha = -1.20 +/- 0.10,
and Ep = 594(-131, +224) keV (chi2 = 79.3/73 dof).
Fitting by GRBM (Band) model yields:
the low-energy photon index is alpha = -1.01 +/- 0.13,
the high energy photon index beta = -1.87(-0.63, +0.15),
the peak energy Ep = 307(-92, +141) keV (chi2 = 76.1/72 dof).

All the quoted errors are at the 90% confidence level.

The Konus-Wind light curve of this GRB is available
at http://www.ioffe.rssi.ru/LEA/GRBs/GRB080319_T44757/


GRB_name: GRB080320A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7488
SUBJECT: GRB 080320: Gemini-N optical afterglow
DATE:    08/03/20 17:00:48 GMT
FROM:    Nial Tanvir at IofA U.Cambridge  <nrt@ast.cam.ac.uk>

N. R. Tanvir, E. Rol (U. Leicester), A. Stephens (Gemini), report
on behalf of a larger collaboration:

We obtained griz observations of the field of GRB 080320 starting
approximately 80 mins post-burst with Gemini-N/GMOS.  Conditions were
rather poor, with some cirrus, which reduced the depth of the images.
A 2nd epoch of i-band imaging was obtained 9 hours post-burst.

A fading point source is seen in both i-band images, somewhat outside
the enhanced XRT error circle (GCN 7479).  The position (J2000) of
this counterpart, with respect to nearby SDSS stars, is (to 0.25
arcsec in each coordinate):

 RA =  11 50 56.427
 dec= +57 09 23.90

The SDSS galaxy noted in GCN 7480 is about 3 arcsec away from the
counterpart, and therefore probably unrelated to it.

Preliminary photometry (again relative to SDSS field stars) gives
i'=22.9, and fading between the epochs of 0.37+/-0.03 mag. This
relatively slow rate of fading could indicate a contribution from a
host galaxy.  The counterpart is seen in the z-band, but is absent (or
very faint) in the r-band image with a limit of about r~24.  This red
r-i colour could be explained by a Lyman-alpha break if the redshift
is z~4.5 to 5.

Further analysis is ongoing.


GRB_name: GRB080320A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7489
SUBJECT: GRB 080320: optical limit
DATE:    08/03/20 19:06:50 GMT
FROM:    Daniele Malesani at Niels Bohr Inst,Dark Cosmology Center  <malesani@astro.ku.dk>

D. Malesani (DARK), A. A. Djupvik, J. Niemela (NOT), J. P. U. Fynbo 
(DARK), report on behalf of a larger collaboration:

We observed the field of GRB 080320 (Grupe et al., GCN 7473) with the 
Nordic Optical Telescope. R-band observations were carried out with the 
StanCam instrument, with mean time 2008 March 20.254 UT (1.47 hr after 
the GRB).

We do not detect any object at the position of the afterglow reported by 
Tanvir et al. (GCN 7488) nor inside the XRT error circle (Goad et al., 
GCN 7479). Our limiting magnitude is R=22 (based on USNO-B1), consistent 
with the nearly-simultaneous measurement of Tanvir et al. (GCNs 7480, 7488).


GRB_name: GRB080319D
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7490
SUBJECT: GRB 080319D: Swift XRT refined analysis
DATE:    08/03/20 20:01:09 GMT
FROM:    Dirk Grupe at PSU/Swift-XRT  <grupe@astro.psu.edu>

Dirk Grupe and Peter Brown (PSU)  report on behalf of the Swift-XRT team:

The Swift-XRT started observing GRB 080319D (trigger=306793, Brown et 
al. GCN
7453) at 17:07:37 UT, 148 seconds after the BAT trigger.

The astrometrically corrected X-ray position (using the XRT-UVOT 
alignment and
matching UVOT field sources to the USNO-B1 catalogue) is: RA, Dec = 
99.47254,
+23.94275 which is equivalent to:

RA (J2000):  06 37 53.41
Dec (J2000): +23 56 33.9

with an uncertainty of 1.7 arcsec (radius, 90% confidence).

The 0.3-10 keV X-ray light curve starts with three flares up to 20 
counts/s. The
afterglow decays very fast and started to flatten at about 1000 s after the
burst. The light curves shows another break at about 5 ks after the 
burst and is
currently decaying with a decay slope of 1.3.

The spectrum of the PC data can be well fit by an absorbed single
powerlaw with photon  index 2.12  0.27 and column density of
 (3.8  1.4)e21 cm-2.  This is in excess of
the Galactic column density of 2.17e21 cm-2 in this direction.
Using this spectrum we estimated a count rate to flux conversion of
1 count/s converts to 6.28e-11 ergs/cm2/s.

If the underlying powerlaw decay continues as is, we predict an XRT 
count rate
of 1.6e-3 counts/s at T+24 hours and 6.5e-4 counts/s at T+48 hours
after the burst, or 1.0e-13 ergs/s/cm2 and 4.1e-14 ergs/s/cm2, 
respectively.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB080320A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7491
SUBJECT: GRB 080320: J detection with FLAMINGOS
DATE:    08/03/20 21:08:10 GMT
FROM:    Adria C. Updike at Clemson U  <aupdike@clemson.edu>

Adria C. Updike, Brian C. Donehew, Ian Oliver, and Dieter H. Hartmann
(Clemson University) report:

We used the Kitt Peak 2.1m telescope and the FLAMINGOS instrument in NIR
imaging mode to obtain J-band exposures of the field of GRB 080320 (GCN
7473, Grupe et al.). In 80 minutes of stacked exposures, we marginally
detect the
afterglow (GCN 7488, Tanvir et al.) at J ~ 20 (using a 2MASS comparison
star located at RA=11:50:47.4, Dec=+57:10:07.41).  The midtime of the
stacked exposures was ~3 hours after the trigger.  Further analysis is
ongoing.

This message may be cited.


GRB_name: GRB080320A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7492
SUBJECT: GRB 080320: Early Super-LOTIS Observations
DATE:    08/03/21 01:56:21 GMT
FROM:    Grant Williams at Steward Observatory  <ggwilli@gmail.com>

G. G. Williams (MMTO) and P. A. Milne (Steward Observatory), on behalf
of the Super-LOTIS Collaboration, report:

The robotic 0.6-m Super-LOTIS telescope began observing the error box
of GRB 080320 (Swift Trigger 306858, Grupe et al. GCN 7473) at
04:38:34.3 UT, 56.3 seconds after the trigger.  Our initial
observations include 5 x 10s exposures, 5 x 20s exposures, and 30 x
60s exposures, all in the R-band.

We do not detect any variable sources or afterglow candidates within
the refined XRT error box (Goad et al. GCN 7479) or at the location of
the OT candidate (Tanvir et al. GCN 7488, Updike et al. GCN 7491) in
any of our single exposures or combined exposures to the following
3-sigma limiting magnitudes:

t_start (UT)    t_end (UT)     exp t (s)     t_start-t_0 (s)    Limit
       coadd?
----------------------------------------------------------------------------------------------------------
04:38:34.3     04:38:44.3     10.0           56.3                R > 17.7      N
04:39:59.3     04:40:19.3     20.0           141.3              R > 18.3      N
04:42:13.7     04:43:13.7     60.0           275.7              R > 19.0      N
04:38:34.3     04:39:52.6     50.0           56.3                R > 18.7      Y
04:39:59.3     04:42:07.0     100.0         141.3               R > 19.4      Y
04:42:13.7     04:47:41.5     300.0         275.7               R > 20.0      Y


GRB_name: GRB080319B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7493
SUBJECT: GRB 080319B - CARMA mm Observations
DATE:    08/03/21 02:06:56 GMT
FROM:    S. Bradley Cenko at Caltech  <cenko@srl.caltech.edu>

D. C.-J. Bock (CARMA), P. C. Chandra (NRAO/UVA), S. R. Kulkarni (Caltech),
D. A. Frail (NRAO), and S. B. Cenko (Caltech) report on behalf of a
larger collaboration:

We have observed the position of GRB080319B (Racusin et al.; GCN 7247)
with the Combined Array for Research in Millimeter-wave Astronomy (CARMA)
at 95 GHz on 2008 March 20 (mean time 11:30 UT). We report a non-detection
at the optical afterlow position with a 3-sigma limit of 0.75 mJy.


GRB_name: GRB080320A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7494
SUBJECT: GRB 080320: Swift XRT refined analysis
DATE:    08/03/21 03:33:14 GMT
FROM:    Dirk Grupe at PSU/Swift-XRT  <grupe@astro.psu.edu>

Dirk Grupe reports on behalf of the Swift-XRT team:


The XRT began observing the field of GRB 080320 (trigger=306858; Grupe 
et al.,
GCN Circ 7473) at 04:40:29.4 UT, 171.0 seconds after
the BAT trigger.

The astrometrically corrected X-ray position (using the XRT-UVOT 
alignment and
matching UVOT field sources to the USNO-B1 catalogue) is: RA, Dec = 
177.7353,
+57.1574 which is equivalent to:

RA (J2000):  11 50 56.46
Dec (J2000): +57 09 26.8

with an uncertainty of 1.4 arcsec (radius, 90% confidence).


The 0.3-10 keV X-ray light curve starts with three flares up to 12 
counts/s.
The afterglow decays very fast and started to flatten at the end of the 
first orbit
about 1000 s after the burst. The light curve is currently decaying with a
shallow decay slope of 0.63 +/- 0.05.

The spectrum of the Photon Counting data of the first three orbits
can be well fitted by an absorbed single powerlaw with a photon
index Gamma = 1.96 +/- 0.20 and column density of (6.9 +/- 4.0)e20 cm-2
This is slightly in excess of the Galactic column density of 1.35e20 
cm-2 in this direction.
Using this spectrum we estimated a count rate to flux conversion of
 1 count/s converts to 4.22e-11 ergs/cm2/s.

If the underlying powerlaw decay continues as is, we predict an XRT 
count rate
of 0.026 counts/s at T+24 hours or 1.1e-12 ergs/s/cm2.


GRB_name: GRB080319A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7495
SUBJECT: GRB 080319A: UVOT Observations
DATE:    08/03/21 11:33:57 GMT
FROM:    Stephen Holland at USRA/NASA/GSFC/SSC  <sholland@milkyway.gsfc.nasa.gov>

S. T. Holland (CRESST/GSFC/USRA) and C. Pagani (PSU) report on behalf
of the Swift/UVOT team:

      The Swift/UVOT observed the field of GRB 080319A starting 542 s
after the BAT trigger (Pagani et al., GCN Circ. 7426).  We detect the
optical afterglow in the white filter at the location of the P60
source (Cenko, 2008, GCN Circ. 7429).

Magnitudes and upper limits are reported below.

Filter    T_start (s) T_stop  Exposure      Mag  Err  Comment
    v          669       1544      432     >20.7       3-sigma UL
    b          767       1480       29     >19.8       3-sigma UL
    u          743       1618       58     >19.9       3-sigma UL
  white        562        662       98      21.1  0.3
               875        975       98     >21.4       3-sigma UL

The above magnitudes are not corrected for the Galactic extinction
corresponding to a reddening of E_{B-V} = 0 .02 mag (Schlegel et al.,
1998, ApJS, 500, 525).  The photometry is on the UVOT flight system
described in Poole et al. (2008, MNRAS, 383,627).  No early-time upper
limits are available for the uvw1, uvm2, and uvw2 filters due to the
lack of data resulting from the slew to GRB 080319B, which occurred 25
minutes after GRB 080319A.


GRB_name: GRB080319B
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7496
SUBJECT: GRB 080319B: UVOT Observations
DATE:    08/03/21 11:34:39 GMT
FROM:    Stephen Holland at USRA/NASA/GSFC/SSC  <sholland@milkyway.gsfc.nasa.gov>

S. T. Holland (CRESST/USRA/GSFC) & J. L. Racusin (PSU) report on
behalf of the Swift/UVOT team:

      The Swift/UVOT observed the field of GRB 080319B starting 51 s
after the BAT trigger (Racusin et al., GCN Circ. 7427).  We detect the
optical afterglow all filters.  Preliminary magnitudes are reported
below.

Filter    T_start (s) T_stop  Exposure      Mag  Err  Comment
    v          175        575      393    <11.5        Saturated
    b          654        664       10     13.39 0.01
    u          630        649       19     12.44 0.01
   uvw1        605        625       19     12.49 0.02
   uvm2        581        600       19     13.39 0.05
   uvw2        685        705       19     13.36 0.04
  white         67        169       98    <13.9        Saturated

The above magnitudes are not corrected for the Galactic extinction
corresponding to a reddening of E_{B-V} = 0 .01 mag (Schlegel et al.,
1998, ApJS, 500, 525).  The photometry is on the UVOT flight system
described in Poole et al. (2008, MNRAS, 383,627).


GRB_name: GRB080319C
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7497
SUBJECT: GRB 080319C: UVOT Observations
DATE:    08/03/21 11:37:34 GMT
FROM:    Stephen Holland at USRA/NASA/GSFC/SSC  <sholland@milkyway.gsfc.nasa.gov>

S. T. Holland (CRESST/USRA/GSFC) & C. Pagani (PSU) report on behalf of
the Swift/UVOT team:

   The Swift/UVOT observed the field of GRB 080319C starting 210 s
after the BAT trigger (Pagani et al., GCN Circ. 7442).  We detect the
optical afterglow in the v, b, u, and white filters at location of the
KAIT optical afterglow (Li, et al., 2008, GCNC 7441).  The UVOT source
position is

RA(J2000) =  17:15:55.49
Dec(J2000) = +55:23:30.6

with an estimated uncertainty of +/-0.53 arcsec (radius, 90%
confidence).

   Magnitudes and upper limits are reported below.

Filter    T_start (s) T_stop  Exposure      Mag  Err  Comment
v          334        353       19     18.09 0.30
b          433        443       10     19.02 0.53
u          408        581       39     19.08 0.36
uvw1        383       2410      214    >20.0        3-sigma UL
uvm2        358       2385      175    >19.6        3-sigma UL
uvw2        463       2336      175    >19.9        3-sigma UL
white        227        327       98     18.81 0.08

The above magnitudes are not corrected for the Galactic extinction
corresponding to a reddening of E_{B-V} = 0 .03 mag (Schlegel et al.,
1998, ApJS, 500, 525).  The photometry is on the UVOT flight system
described in Poole et al. (2008, MNRAS, 383,627).  The non-detections
in the three ultraviolet filters may indicate that the redshift is
z >~ 3.


GRB_name: GRB080319D
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7498
SUBJECT: GRB 080319D, Swift-BAT refined analysis
DATE:    08/03/21 13:15:13 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

T. Ukwatta (GWU) S. D. Barthelmy (GSFC), P. J. Brown (PSU),
J. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC),
H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), K. McLean (GSFC/UMD),
D. Palmer (LANL), A. Parsons (GSFC), T. Sakamoto (GSFC/UMBC),
G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC)
(i.e. the Swift-BAT team):
 
Using the data set from T-239 to T+963 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 080319D (trigger #306793)
(Brown, et al., GCN Circ. 7453).  The BAT ground-calculated position is
RA, Dec = 99.479, 23.982 deg which is 
   RA(J2000)  =  06h 37m 55.0s 
   Dec(J2000) = +23d 58' 56.0" 
with an uncertainty of 2.6 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 59%.
 
The mask-weighted light curve shows a roughly symmetric peak starting
at ~T+0, peaking at ~T+23, and ending at ~T+50 sec.
T90 (15-350 keV) is 24 +- 4 sec (estimated error including systematics).
 
The time-averaged spectrum from T+5.0 to T+34.5 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.92 +- 0.35.  The fluence in the 15-150 keV band is 3.2 +- 0.7 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+25.35 sec in the 15-150 keV band
is 0.1 +- 0.1 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/306793/BA/


GRB_name: GRB080319B
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7499
SUBJECT: GRB080319B: Time-Independent XRT Spectrum
DATE:    08/03/21 16:41:56 GMT
FROM:    Nat Butler at MIT/CSR  <nrbutler@space.mit.edu>

Nat Butler (UC Berkeley) reports:

I have applied our time-dependent pileup correction code (Butler &
Kocevski 2007; ApJ, 663, 407) to the XRT spectrum of GRB080319B (see, Racusin
et al., GCN 7459).  Although I find similar temporal properties in the     
afterglow decay to those quoted by the XRT team, I find significantly
different spectral properties.  Notably, there is no significant evidence
for a time-variation in N_H and no significant need for a thermal component.
The WT model (0.4-10 keV) and PC mode (0.3-10 keV) spectra fitted jointly
and well (chi^2/nu=799.70/788) with an absorbed powerlaw yields:

Gamma = 1.84+/-0.01
N_H = 1.7+/-0.1 x 10^21 cm^(-2) @ z=0.937 (Vreeswijk et al., GCN 7451), in 
  addition to the expected Galaxy contribution along the line of sight.  Here 
  we assume the solar chemical abundances from Anders & Ebihara (1982).
  This value of N_H implies ~2 mag extinction in the observer frame V band
  assuming the mean Galactic dust+gas properties.

Allowing the photon indices to vary separately: Gamma1=1.84^{+0.1}_{-0.2} and 
Gamma2=1.85+/-0.05, closely consistent.  The fractional possible increase in 
rest-frame N_H between the WT mode data (t=660s to 4.95 ksec) and the PC mode 
data (t=4.95 to 174 ksec) is modest and weakly significant: 
0.74^{+0.43}_{-0.37}%.  I suspect the indicated variations are purely due to 
calibration uncertainties in the WT mode data.  The hard WT mode spectral fit 
in GCN 7459 can be reproduced by relaxing our pileup correction.

Additional evidence disfavors an interpretation of an evolving X-ray
spectrum:

Time resolved fits to the WT mode data show no significant evidence for
spectral evolution in the WT mode data considered alone. See,
http://astro.berkeley.edu/~nat/080319B_spec.jpg

The light curve is a simple (broken) powerlaw for the WT mode data, with
no flaring.  Afterglows with such light curves typically exhibit weak
or no spectral evolution (e.g., Butler & Kocevski 2007, ApJ, 668, 400).
There is no significant variations in the X-ray hardness ratio for this event.
See, http://astro.berkeley.edu/~nat/080319B_hardness.jpg

A fit to BAT data (see also, Cummings et al., GCN 7462) in a time     
region (58s to 303s; chi^2/nu=36.46/55) overlapping the XRT observation has
a roughly consistent powerlaw (Gamma=2.1+/-0.1), and also allows for a
smooth extrapolation in flux between BAT and XRT assuming a simple powerlaw
model connecting the flux in both instruments.

This message can be cited.


GRB_name: GRB080319D
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7500
SUBJECT: GRB 080319D: optical upper limit
DATE:    08/03/21 17:57:03 GMT
FROM:    Giuseppe Greco at U Bologna  <giuseppe.greco2@studio.unibo.it>

G. Greco (Bologna University), F. Terra (Second University of
Roma "Tor Vergata"), C. Bartolini, A. Guarnieri, A. Piccioni
(Bologna University), F. Munz, G. Pizzichini (INAF/IASF Bologna),
D. Nanni (INAF/OAR and Second University of Rome "Tor Vergata"),
A. Shearer (Centre for Astronomy, Galway), 
R. Gualandi (Bologna Observatory) report:


We observed the field of GRB 080319D (Brown et al., GCN 7453)
with the 152 cm telescope located in Loiano, under unfavourable
conditions due to full moon light.

One Rc-band observation (1x600 sec) was done on 2008
March at 20.779 UT middle exposure time.

We do not detect any object at the position of the candidate
afterglow reported by Immler et al. (GCN 7458).
Our 3-sigma limiting magnitude is R~20 (based on the Nomad1 catalogue).

The image has been posted in our public directory
from where it can be retrieved
by sftp using
hostname: ermione.bo.astro.it
username: publicGRB
password: GRB_bo.
directory: GRB080319D


GRB_name: GRB080319B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7501
SUBJECT: GRB 080319B: optical upper limit
DATE:    08/03/21 18:51:16 GMT
FROM:    Giuseppe Greco at U Bologna  <giuseppe.greco2@studio.unibo.it>

G. Greco (Bologna University), F. Terra (Second University of
Roma "Tor Vergata"), C. Bartolini, A. Guarnieri, A. Piccioni
(Bologna University), F. Munz, G. Pizzichini (INAF/IASF Bologna),
D. Nanni (INAF/OAR and Second University of Rome "Tor Vergata"),
A. Shearer (Centre for Astronomy, Galway), R. Gualandi 
(Bologna Observatory) report:

We observed the field of GRB 080319B (GCN 7427, Racusin et al.)  
with the 152 cm telescope located in Loiano under unfavorable
conditions due to the illumination of the full moon. 

By adding four consecutive 10 min exposures in the Rc filter at 
mean time 2008 March 20.947 UT we do not detect any object at
the position of the optical bright afterglow reported by 
Racusin et al. (GCN 7428).

Our 3-sigma limiting magnitude is R~20.3 (based on Nomad1 catalogue).

The image has been posted in our public directory 
from where it can be retrieved 
by sftp using 
hostname: ermione.bo.astro.it
username: publicGRB
password: GRB_bo.
directory: GRB080319B


GRB_name: GRB080319B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7502
SUBJECT: GRB 080319B: TORTORA light curve
DATE:    08/03/21 19:54:17 GMT
FROM:    Sergey Karpov at SAO RAS  <karpov@sao.ru>

S. Karpov, G. Beskin (SAO RAS, Russia), S. Bondar (RIPI, Russia), C. Bartolini,
G. Greco, A. Guarnieri, A. Piccioni (Astronomy Department of Bologna
University, Italy), D. Nanni, F. Terra (Second University of Roma "Tor
Vergata", Italy), E. Molinari, G. Chincarini, F.M. Zerbi, S. Covino, V. Testa
(Osservatorio Astronomico di Brera, Italy), G. Tosti (Universita di Perugia,
Italy), F. Vitali, L.A. Antonelli (Osservatorio Astronomico di Roma, Italy),
P. Conconi, G.  Cutispoto (Osservatorio Astronomico di Catania, Italy),
G. Malaspina (Osservatorio Astronomico di Brera, Italy), L. Nicastro (Istituto
di Astrofisica Spaziale e Fisica Cosmica, Palermo, Italy), E. Palazzi (Istituto
di Astrofisica Spaziale e Fisica Cosmica, Bologna, Italy), E. Meurs (Dunsink
Observatory, Ireland), P.  Goldoni (Observatori Astronomic - Universitat de
Valencia Edificio de Institutos de Investigacion, Spain)

report on behalf of TORTOREM team:

Following GCN 7452 we publish a preliminary light curve of GRB 080319b with
reduced temporal resolution (10 frames time binning, 1.3 seconds effective
exposure, no gaps between frames). The photometry is performed in instrumental
system and calibrated towards the V magnitudes of nearby Tycho2 stars. The
light curve is available online at

http://vo.astronet.ru/~karpov/grb080319b_lc_10.gif

The light curve shows fast (~5 seconds) uprise towards the peak V=5.5 at T+23,
complex multi-peak structure till T+50 and featureless decay then. In total,
the transient has been visible for ~65 seconds; 6 seconds in the T+30 - T+36
interval are currently excluded from the analysis due to repointing of REM
telescope at that time.

The light curve is consistent with the one published by Pi of the Sky (Cwiok et
al, GCN 7445).

The video sequence of the data is available at

http://vo.astronet.ru/~karpov/grb080319b.avi

and with reduced temporal resolution at

http://vo.astronet.ru/~karpov/grb080319b_lowres.avi

The results of analysis of full-resolution (0.13s exposure) data will be
published later.


GRB_name: GRB080319D
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7503
SUBJECT: GRB 080319D: GROND Observations
DATE:    08/03/21 20:53:09 GMT
FROM:    Christian Clemens at MPE  <cclemens@mpe.mpg.de>

C. Clemens, S. Klose (Tautenburg Obs.), J. Greiner, A. Kupcu Yoldas, A. 
Yoldas, T. Kruehler and G. Szokoly (Eoetvoes Univ., Budapest and MPE 
Garching) (all others MPE Garching) report on behalf of the GROND team:

We observed the field of GRB 080319D (SWIFT trigger 306793; P. J. Brown et 
al., GCN 7453) simultaneously in g', r', i', z', J, H and K with GROND 
(Greiner et al. 2008, PASP) mounted at the 2.2m ESO/MPI telescope at La Silla 
Observatory (Chile).

Observations started at 00:15 UT on March 20th, 2008, about 7.2 hrs after the 
GRB trigger at an airmass of 1.7 to 2.5. We obtained 0.5 hrs of total 
integration time in g', r', i' and z' and found a source, which might be the 
host galaxy, also present in the DSS2 red images at

RA (J2000) = 06h 37m 53.56s
DEC (J2000) = 23d 56' 34.2''

within the 0.5'' Swift UVOT error circle reported by S. Immler et al. in GCN 
7458. The object is seen in all bands except K, implying a redshift smaller 
than 3.5.

Our co-added images reveal roughly estimated magnitudes of g' = 21.3, r' = 
20.7, i' = 19.9 and z' = 19.7, calibrated against USNO-B catalogue stars.

No statement about variability, i.e. an additional contribution from afterglow 
light, can be made at this point. Further observations are planned.


GRB_name: GRB080319B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7504
SUBJECT: GRB 080319B: Optical observation (Brno, CZ)
DATE:    08/03/21 21:58:31 GMT
FROM:    Rudolf Novak at N.Copernicus Obs/Czech Rep  <exebece@gmail.com>

We observed GRB 080319B using 40cm Newtonian telescope, SBIG ST-7XMEi
CCD camera and R-band Kron-Cousins filter. We found afterglow to be
R=20.0+-0.3 mag at 2008.03.20 0.125 UT. Given time is mid-exposure
(total exposure: 6.7h). Weather conditions were poor because of clouds
and Moon. We used 13 nearby USNO-B1.0 stars to get R magnitude. An
aperture photometry package Munipack
(http://adsabs.harvard.edu/abs/1998stel.conf...30H) was used for data
reduction.

Rudolf Novak
Nicholas Copernicus Observatory & Planetarium in Brno, Czech Republic
(http://ccd.astronomy.cz)

Filip Hroch
Masaryk University, Brno
(http://monteboo.blogspot.com)


GRB_name: GRB080320A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7505
SUBJECT: GRB 080320, Swift-BAT refined analysis
DATE:    08/03/22 14:06:04 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

K. McLean (GSFC/UMD), S. D. Barthelmy (GSFC), J. Cummings (GSFC/UMBC),
E. Fenimore (LANL), N. Gehrels (GSFC), D. Grupe (PSU),
H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), D. Palmer (LANL),
A. Parsons (GSFC), T. Sakamoto (GSFC/UMBC), G. Sato (GSFC/ISAS),
M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-119 to T+183 sec from the telemetry downlinks,
we report further analysis of BAT GRB 080320 (trigger #306858)
(Grupe, et al., GCN Circ. 7473).  The BAT ground-calculated position is
RA, Dec = 177.763, 57.162 deg, which is 
   RA(J2000)  =  11h 51m 03.1s 
   Dec(J2000) = +57d 09' 42.6" 
with an uncertainty of 1.8 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 93%.
 
The mask-weighted light curve shows a FRED peak starting at ~T-5 sec,
peaking at ~T+0, and ending at ~T+35 sec.  There a possible (3 sigma)
precursor peak at ~T-55 sec with a width of about 5 sec.
T90 (15-350 keV) is 14 +- 2 sec (estimated error including systematics).
 
The time-averaged spectrum from T-1.7 to T+13.8 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.70 +- 0.22.  The fluence in the 15-150 keV band is 2.7 +- 0.4 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+0.15 sec in the 15-150 keV band
is 0.6 +- 0.1 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/306858/BA/


GRB_name: GRB080319B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7506
SUBJECT: Radio Detection of GRB 080319B
DATE:    08/03/22 21:08:48 GMT
FROM:    Alicia Soderberg at Caltech  <ams@astro.caltech.edu>

Alicia Soderberg (Princeton),  Poonam Chandra (U. Virginia), and Dale
Frail (NRAO) report on behalf of a larger collaboration:

"We observed the field of GRB 080319B (GCN 7427) with the Very 
Large Array beginning at Mar 21.56 UT.  At 4.86 GHz we detect a radio 
source coincident with the optical afterglow position (GCN 7428) at
coordinates (J2000):

RA =  14 31 41.01   +/-  0.05
Dec = 36 18 09.7    +/-   0.4

with flux density 189 +- 39 microJy.  Further observations are scheduled.

The National Radio Astronomy Observatory is a facility of the National
Science Foundation operated under cooperative agreement by Associated
Universities, Inc."


GRB_name: GRB080319B
Detection_method: VLA Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7507
SUBJECT: GRB 080319B: Second & Third Epoch WSRT Radio Observations
DATE:    08/03/23 02:43:15 GMT
FROM:    Alexander van der Horst at NASA/MSFC  <avdhorst@science.uva.nl>

A.J. van der Horst (NASA/ORAU) reports on behalf of a large collaboration:

"We re-observed the position of the GRB 080319B afterglow at 4.9 GHz with
the Westerbork Synthesis Radio Telescope at March 21.84 to 22.03 UT and at
March 22.84 to 23.03 UT, i.e. 2.7 and 3.7 days after the burst (GCN 7427).

We do not detect a radio source at the position of the optical counterpart
(GCN 7428) at 2.7 days. The three-sigma rms noise in the map around that
position is 108 microJy per beam. We note that this upper limit is not
consistent with the almost simultaneous VLA detection at 4.86 GHz reported
in GCN 7506.
We tentatively detect a radio source at 4 sigma significance at 3.7 days,
with a flux density of 163 +/- 39 microJy.

We would like to thank the WSRT staff for scheduling and obtaining these
observations."


GRB_name: GRB080319C
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7508
SUBJECT: GRB 080319C: Suzaku WAM observation of the prompt emission
DATE:    08/03/23 23:47:34 GMT
FROM:    Makoto Tashiro at Saitama U/Swift  <tashiro@phy.saitama-u.ac.jp>

K.Onda, M. Tashiro, Y. Terada, Y. Urata, A. Endo,
M. Suzuki, N. Kodaka, K. Morigami (Saitama U.),
M. Ohno, T. Uehara, T. Takahashi, Y. Fukazawa,
C. Kira, Y. Hanabata (Hiroshima U.), T. Tamagawa (RIKEN),
K. Yamaoka, Y. E. Nakagawa, S. Sugita (Aoyama Gakuin U.),
T. Enoto, R. Miyawaki, K. Nakazawa, K. Makishima (Univ. of Tokyo),
E. Sonoda, M. Yamauchi, H. Tanaka, R. Hara (Univ. of Miyazaki),
M. Kokubun, M. Suzuki, T. Takahashi (ISAS/JAXA), S. Hong (Nihon U.),
on behalf of the Suzaku WAM team, report:

The long GRB 080319C (Swift/BAT trigger #306778 ; Pagani et al.,
GCN 7442) triggered the Suzaku Wide-band  All-sky Monitor (WAM)
which covers an energy range of 50 keV - 5 MeV at 12:25:56 UT (=T0).
The observed light curve shows a multi-peaked structure starting at T0s,
ending at T0+14s with a duration (T90) of about 13 seconds.
The fluence in 100 - 1000 keV was 6.4(+0.4, -0.9)*10^-6 erg/cm^2.
The 1-s peak flux measured from T0+2s was 4.2(+0.2, -0.3) photons/cm^2/s
in the same energy range.

Preliminary result shows that the time-averaged spectrum from
T0s to T0+13s is well fitted by a power-law with exponential cutoff model:
   dN/dE ~  E^{-alpha} * exp(-(2-alpha)*E/Epeak) with
   alpha       0.67(+0.30, -0.36), and
   Epeak       761(+255, -136) keV (chi^2/d.o.f. = 32.2/23).

All the quoted errors are at statistical 90% confidence level,
in which the systematic uncertainties are not included.
The light curves for this burst are available at:
 
http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html


GRB_name: GRB080319B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7509
SUBJECT: GRB 080319B: Spitzer Mid-infrared Observations
DATE:    08/03/24 05:59:23 GMT
FROM:    S. Bradley Cenko at Caltech  <cenko@srl.caltech.edu>

H. Teplitz (IPAC), M. Werner (JPL), S. B. Cenko, S. R. Kulkarni and A. Rau
(Caltech) report on behalf of a larger collaboration:

We have imaged the field of GRB080319B (Racusin et al., GCN 7427) with the
blue filter (15.8 um) of the IRS peak-up camera on board the Spitzer Space
Telescope.  Observations consisted of 60 pointings, each with two dithered
30 s cycles, beginning at March 21.81 UT (~ 2.55 d after the burst).  At
the location of the optical afterglow, we measure a flux density of 35.7
+/- 3.9 uJy.

We wish to thank the entire Spitzer team for the prompt execution of these
observations.


GRB_name: GRB080319B
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7511
SUBJECT: GRB 080319B : Apparent spectral evolution in very early Swift/XRT WT mode data: intrinsic or pile-up effect?
DATE:    08/03/24 22:35:33 GMT
FROM:    Binbin Zhang at UNLV  <zbb@physics.unlv.edu>

Bin-Bin Zhang (University of Nevada Las Vegas), Enwei Liang (Guangxi 
University, China) and Bing Zhang (University of Nevada Las Vegas) report:

We have processed the Swift XRT data of GRB 080319B, paying special 
attention to the possible spectral evolution in the WT mode data 
(Racusin et al. GCN 7459; cf. Butler GCN 7499). We perform a 
time-dependent spectral analysis using the method described in (Zhang, 
Liang & Zhang 2007, ApJ, 666, 1002). Since the early data are strongly 
affected by photon pile-up, we use a box annulus region for the WT mode 
data (outer radius 40*20, inner radius 8*20; see also Racusin et al. GCN 
7459) and time-dependent circle annulus regions for the PC mode data to 
extract spectra and lightcurves. We fit the time-dependent spectra using 
a simple power-law model with the absorption from the MilkyWay Galaxy 
(NH_G=1.12e20 cm^{-2} ) and from the host galaxy (NH_host=7.3e20 
cm^{-2}, obtained from fitting to the integrated 1st orbit WT mode 
spectrum). We confirm Butler (GCN 7499) that the apparent spectral 
evolution after 200 seconds is due to instrumental "pile up" effect. 
However, in the very early time t ~ (68-100) seconds, an apparent weak 
but significant hard-to-soft spectral evolution sustains even if we take 
into account the pile-up corrections. The photon index evolves from 1.67 
Â± 0.02 to 1.77 Â± 0.02 during this period. Our results can be found at 
http://grb.physics.unlv.edu/~xrt/xrtweb/080319B/080319B.html.

To make sure that this early-time spectral evolution is not due to the 
pile-up effect, we extract the time-dependent spectra with box annuli 
having different sizes. By excluding the central regions, we enlarge the 
outer radius up to 80 pixel * 20 pixel to make sure that there are 
enough photons for the spectral analysis. Our tests show that even if 
the inner box size is as large as 30 pixel * 20 pixel (spectra in annuli 
with such a large inner radius is not possible to be affected by the 
pile-up effect), the early time (before 200 seconds) XRT WT data still 
show significant spectral evolution. We therefore cautiously conclude 
that this early spectral evolution is likely intrinsic.

Strong hard-to-soft spectral evolution has been seen in the early steep 
decay phase of many GRB X-ray afterglows (e.g. Zhang et al. 2007, 666, 
1002), which points towards a non-forward-shock origin of the emission. 
We notice that the lightcurve before 200 seconds show several weak 
flaring/flicking features, which is more easily seen in linear scale 
(see http://grb.physics.unlv.edu/~xrt/xrtweb/080319B/earlylc.png). In 
view that some steep decay segments with overlapping flares typically 
show hard-to-soft spectral evolution (Group C in Zhang et al. 2007), we 
suspect that the weak spectral evolution in this burst is also related 
to the weak flaring/flicking features. It is however puzzling why this 
segment naturally transforms to a smooth decay after 200 seconds which 
show no further spectral evolution.

Throughout our fit we have fixed the NH_host values. Another possibitly 
is that the apparent spectral evolution is caused by a varying NH_host 
value (Racusin et al. GCN 7459). We test such a scenario by fixing the 
photon index to \Gamma=1.76 (average value after 200s) and fit the 
time-dependent spectra before 200s using the same model 
(wabs*zbwas*zwabs) but allowing NH_host to be a free parameter.  We 
obtain acceptable fits, and found that the NH_host in the early time 
evolves dramatically to one half of its initiall valve (from ~ 1.1e21 
cm^{-2} to ~ 6.6e20 cm^{-2}). The time evolution of the NH_host value 
can be found at http://grb.physics.unlv.edu/~xrt/xrtweb/080319B/nh.png. 
This is another plausible physical scenario, although a model for the 
rapid depletion of NH_host is called for.

The reduced chi2 in our fitting to the wabs*zwabs*powerlaw model is 
typically ~1. Although a possible thermal component has been suggested 
(cf. Racusin et al. GCN 7459), in our fitting no thermal component is 
required by the data.

This message can be cited.


GRB_name: GRB080325A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7512
SUBJECT: GRB 080325: Swift detection of a burst
DATE:    08/03/25 04:25:22 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

L. Vetere (PSU), P. J. Brown (PSU), D. Grupe (PSU),
C. B. Markwardt (CRESST/GSFC/UMD), C. Pagani (PSU),
D. M. Palmer (LANL), J. L. Racusin (PSU), M. C. Stroh (PSU) and
T. N. Ukwatta (GSFC/GWU) report on behalf of the Swift Team:

At 04:09:17 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 080325 (trigger=307604).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 277.895, +36.511 which is 
   RA(J2000) = 18h 31m 35s
   Dec(J2000) = +36d 30' 38"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  Because this is a 64-sec long image trigger, the
TDRSS lightcurve does not show any significant signal (as is typical). 

The XRT began observing the field at 04:11:49.2 UT, 151.9 seconds after
the BAT trigger. XRT found a bright, uncatalogued X-ray source located
at RA, Dec 277.8920, +36.5221 which is equivalent to:
   RA(J2000)  = 18h 31m 34.0s
   Dec(J2000) = +36d 31' 19.5"
with an uncertainty of 4.7 arcseconds (radius, 90% containment). This
location is 40 arcseconds from the BAT onboard position, within the BAT
error circle. No event data are yet available to assess possible
redshift constraints using X-ray spectroscopy and the nH-z relation
from Grupe et al. (2007). 


UVOT took a finding chart exposure of 100 seconds with the White (160-650 nm)
filter starting 162 seconds after the BAT trigger. No afterglow candidate has
been found in the initial data products. Image catalog data are not available
at this time. The 8'x8' region for the list of sources generated on-board
covers 100% of the XRT error circle. The list of sources is typically complete
to about 18 mag. No correction has been made for the expected extinction
corresponding to E(B-V) of 0.06. 




Burst Advocate for this burst is L. Vetere (vetere AT astro.psu.edu). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB080325A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7513
SUBJECT: GRB 080325: Enhanced Swift-XRT position
DATE:    08/03/25 11:21:05 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 199 s of overlapping XRT Photon Counting mode and UVOT
data for GRB 080325, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 277.89272, +36.52381 which is equivalent
to:

RA (J2000): 18h 31m 34.25s
Dec (J2000): +36d 31' 25.7"

with an uncertainty of 2.6 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest position
can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is
described by Goad et al. (2007, A&A, 476, 1401
http://www.swift.ac.uk/xrt_positions/Goad.pdf), the current algorithm is an
extension of this method.

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB080319D
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7514
SUBJECT: GRB 080319D: GROND Detection of the Optical Counterpart
DATE:    08/03/25 12:41:09 GMT
FROM:    Christian Clemens at MPE  <cclemens@mpe.mpg.de>

C. Clemens, S. Klose (Tautenburg Obs.), J. Greiner, A. Kupcu Yoldas, A. 
Yoldas, T. Kruehler and G. Szokoly (Eoetvoes Univ., Budapest and MPE 
Garching) (all others MPE Garching) report on behalf of the GROND team:

We observed the field of GRB 080319D for a second time at 23:43 UT on March 
23rd, 2008, about 4.3 days after the GRB trigger with 0.5 hrs of total 
integration time in g', r', i' and z'.

We do not detect any object within the Swift UVOT error circle (S. Immler et 
al., GCN #7458) to the following 3-sigma upper limits:

g' > 24.7, r' > 23.4, i' > 22.7 and z' > 22.5.

This indicates a clear fading of the optical afterglow compared to our first 
epoch observations (C. Clemens et al., GCN #7503).


GRB_name: GRB080325A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7515
SUBJECT: GRB 080325: NIR afterglow candidate
DATE:    08/03/25 15:43:08 GMT
FROM:    Adria C. Updike at Clemson U  <aupdike@clemson.edu>

Adria C. Updike, Brian C. Donehew, Ian Oliver, and Dieter H. Hartmann
(Clemson University) report:

We imaged the field of GRB 080325 (Vetere et al., GCN 7512) with the KPNO
2.1m + FLAMINGOS in the J band beginning 5 hours and 42 minutes after the
trigger.  Within the enhanced XRT position (Osborne et al., GCN 7513), we
detect a source at RA = 18:31:34.185, Dec = +36:31:19.60 (+/- 2
arcseconds).

Days after trigger        Band      Magnitude
--------------------------------------------------
0.23775                    J        18.76 +/- 0.14
0.25022                    J        18.85 +/- 0.13
0.26427                    J        19.42 +/- 0.26

Magnitudes are derived relative to the 2MASS catalog.  This sequence
suggests a fading source.  Further observations are required to confirm
this detection.

This message may be cited.


GRB_name: GRB080325A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7516
SUBJECT: GRB 080325: Early observations from OSN
DATE:    08/03/25 18:33:39 GMT
FROM:    Antonio Deugarte at IAA-CSIC  <deugarte@iaa.es>

A. de Ugarte Postigo (ESO, Chile), A. Sota,
J.Gorosabel, A.J. Castro-Tirado (IAA-CSIC) report,

We have observed the field of GRB 080325  (Vetere et al.
GCN 7512) with the 1.5m OSN telescope at Sierra Nevada
Observatory (Granada, Spain) starting at 04:23:01 UT, 12.48
minutes after the burst. Inside the initial XRT error box
there is an object with coordinates R.A.: 18:31:34.13
Dec.: +36:31:19.8 (J2000 +/- 0.5"), which is also present in
the DSS, consistent with the coordinates reported by
Updike et al. (GCN 7515). Inside the refined XRT error box
(Osborne et al. GCN 7513) we do not detect any new source
down to the following 3-sigma limits (t-t0 being the mean
observing time since the GRB):

(t-t0) (min)  |  Exp. time  (s)   |  I-band limit
12.65          |  20                     |  > 19.5
14.36          | 9x20                  |  > 20.8
39.46          | 2300s                |  > 21.8

This message may be cited


GRB_name: GRB080319C
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7517
SUBJECT: GRB 080319C: Gemini-North spectroscopic redshift
DATE:    08/03/25 18:37:49 GMT
FROM:    Klaas Wiersema at U of Leicester  <kw113@star.le.ac.uk>

K. Wiersema, N. Tanvir (University of Leicester), P. Vreeswijk, J. Fynbo 
(DARK Cosmology Centre), R. Starling, E. Rol (Leicester) and P. Jakobsson 
(Hertfordshire) report on behalf of a large collaboration:

We observed the afterglow of GRB 080319C (GCN 7442) with Gemini North, 
using the GMOS-N instrument. We took spectra using the B600 grism 
(exposure time 4 x 900s) in bad weather conditions: exposures were taken 
through holes in the cloud deck. Observations started at 14:51 UT on
March 19th.

The spectrum shows several absorption lines of C IV, Al II, Si II, Al III, 
Mg I and the CrII / ZnII blend. From these we find the redshift z = 1.95.

We are very grateful to the Gemini staff, in particular Paul Hirst, for 
executing these observations.


GRB_name: GRB080325A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7518
SUBJECT: GRB 080325: Swift/UVOT Upper Limits
DATE:    08/03/25 20:25:03 GMT
FROM:    Peter Brown at PSU  <pbrown@astro.psu.edu>

P. J. Brown and L. Vetere (PSU) report on behalf
of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field
of GRB 080325 (trigger=307604) starting 163 s after
the BAT trigger (Vetere et al., GCN Circ. 7512).
We do not detect an optical/uv afterglow at the
enhanced XRT position (Osborne et al., GCN Circ. 7513),
or NIR candidate (Updike et al., GCN Circ. 7515) in
the initial finding chart observations or subsequent
summed images down to the following 3 sigma upper limits:

Filter    T_start (s) T_stop  Exposure      MagLimit
 white        163        262       98     >20.6
 white        163       5905      392     >21.5
   v          269        513      240     >19.3
   v          269       6297      419     >19.6
   b         5501       5700      197     >20.6
   u         4131      22211      353     >20.9
   uvw1      3925      21975     2371     >21.8
   uvm2      3720      10211      891     >21.1
   uvw2      5912       6111      197     >20.1

The above magnitudes are not corrected for the Galactic
extinction corresponding to a reddening of
E(B-V) = 0 .064 mag (Schlegel et al.,1998, ApJS, 500, 525).
The photometry is on the UVOT flight systemdescribed in
Poole et al. (2008, MNRAS, 383,627).


GRB_name: GRB080319B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7519
SUBJECT: GRB080319B: optical observations 
DATE:    08/03/25 21:41:49 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

Yu. Krugly,  I. Slyusarev (Institute of Astronomy of Kharkiv National 
University), A. Pozanenko (IKI) report on behalf of larger collaboration:

We observed the afterglow of GRB080319B (Racusin et al. GCN 7427) with 0.7m 
telescope of Institute of Astronomy, Kharkiv National Univ. starting on (UT) 
March 19, 18:20 and continuing to March 20, 02:44. The series consist of 
continuous observations in R and a few frames were taken in V around (UT) 
19:58.

The afterglow  (Racusin et al. GCN 7427, Holland et al. GCN 7428, Li et al. 
GCN 7430) is detected in the obtained single images.

Preliminary photometry of combined images reveals a possible rapid decline 
of the light curve between (UT, mid time) 18:25 (R~19.1) and 19:04 (R~19.9) 
and then light curve flattering toward the end of observation March 20 (UT) 
02:00 (R~20.1). The light curve between (UT) 19:00 and 02:39 is close to a 
constant and  not compatible with power law decay index of alpha=1.2.

The magnitude of the comparison star is based on SDSS calibration (Cool et 
al, GCN 7465).
The message may be cited. 


GRB_name: GRB080325A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7520
SUBJECT: GRB 080325: GROND Observations
DATE:    08/03/25 22:56:25 GMT
FROM:    Christian Clemens at MPE  <cclemens@mpe.mpg.de>

C. Clemens, A. Kupcu Yoldas, J. Greiner, A. Yoldas, T. Kruehler and G. Szokoly 
(Eoetvoes Univ., Budapest and MPE Garching) (all others MPE Garching) report 
on behalf of the GROND team:

We observed the field of GRB 080325 (Swift trigger 307604; L. Vetere et al., 
GCN #7512) simultaneously in g', r', i', z', J, H and K with GROND (Greiner 
et al. 2008, PASP) mounted at the 2.2m ESO/MPI telescope at La Silla 
Observatory (Chile).

Observations started at 09:50 UT on March 25th, 2008, about 5.7 hrs after the 
GRB trigger. We obtained 20 mins of total integration time in J, H and K 
during morning twilight.

We do not detect any new source within the 2.6'' enhanced Swift-XRT error 
circle reported by J. Osborne et al. (GCN #7513) to the following 3-sigma 
upper limits:

J > 20.4, H > 19.4 and K > 19.0.

We also detect the afterglow candidate, about 6" south of the centre of the 
enhanced Swift-XRT error circle, reported by A. Updike et al. (GCN #7515) to 
following magnitude:

J = 18.60 +/- 0.06,

calibrated against 2MASS catalogue stars.


GRB_name: GRB080325A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7521
SUBJECT: GRB080325: XRT Refined Analysis
DATE:    08/03/25 23:24:28 GMT
FROM:    Loredana Vetere at PSU  <vetere@astro.psu.edu>

L. Vetere, J. L. Racusin (PSU) report on behalf of the Swift-XRT team:

We have analysed the first 8 orbits of Swift-XRT data obtained for BAT GRB
080325 (trigger 307604, Vetere et al., GCN Circ. 7512).

The data consist of 360 s in Windowed Timing (WT) mode, starting 160 s after the
BAT trigger and 7.8 ks in Photon Counting (PC) mode. The astrometrically
corrected X-ray position is given  in Osborne et al. GCN 7513.

The early WT light-curve shows flaring activity followed by a fast decay that
can be fit by a power law with a slope of alpha1=5.7  0.5. The following PC
light curve starts at 3.6 ks after BAT trigger and shows a much slower decay
with a slope of alpha2=0.8  0.2. If the light-curve continues to decay at the
same rate, we predict an XRT count rate of 0.011 count/s at T+24 hours.

The spectrum formed from all the WT data can be modeled with a power-law of
photon index Gamma = 2.4  0.1, with an absorbing column of NH = (3.0  0.1)e21
cm^-2, significantly in excess with respect to the Galactic value of 3.81e20
cm^-2.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB080325A
Detection_method: MITSuME
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7522
SUBJECT: GRB 080325: MITSuME Akeno optical upper limits
DATE:    08/03/26 07:40:25 GMT
FROM:    Nobuyuki Kawai at Tokyo Tech  <nkawai@hp.phys.titech.ac.jp>

Y. Kudou, T. Shimokawabe and N. Kawai (Tokyo Tech) report on behalf of
the MITSuME collaboration: 

We observed the error box of GRB 080325 (L. Vetere et al. GCN 7512)
with the 3-color 50cm MITSuME Telescope at Akeno, Japan starting
at 16:51:16 Mar 25 UT, 12.7 hr after the trigger under a poor sky
condition at a low altitude.
In the co-added images of Ic, Rc, and g' bands, we did not detect
any afterglow candidate in the XRT error circle.  
The 3-sigma limiting magnitudes based on USNO-B1.0 (I-band) and NOMAD
(R-band,g'-band) stars are following.

Filter   start time   end time    Exposure   Mag (3-sigma upper limit)
-----------------------------------------------------------------
g'     16:51:16      17:54:41     15 x 60 s     17.2
Rc     16:51:16      17:54:41     15 x 60 s     16.4
Ic     16:51:16      17:54:41     15 x 60 s     17.0
-----------------------------------------------------------------


GRB_name: GRB080310A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7523
SUBJECT: GRB080310, late-time photometry with LBT
DATE:    08/03/26 16:22:55 GMT
FROM:    Peter Garnavich at U of Notre Dame  <pgarnavi@nd.edu>

J. Hill (LBTO/UAz), R. Ragazzoni, A. Baruffolo (Padova), and
P. Garnavich (Notre Dame) report:

The Large Binocular Telescope (LBT) observed the position of GRB 080310
(Chornock et al. GCN 7381; Cummings et al., GCN 7382) with the
LBC red and blue cameras between March 19.3 and 19.5 (UT). Twenty
200 sec exposures in the Sloan-r filter were obtained in 1.3"
seeing and with a significant sky background from the Moon.

The combined image shows a faint source present at the position
of the afterglow. From stars calibrated in the SDSS we estimate
the brightness of the source to be r=25.4+/-0.2 mag. This is
consistent with an afterglow  power-law decay index of 2.4 between
2 and 9 days after the burst (Wegner et al., GCN 7423). The
true afterglow decay rate could be steeper if host galaxy light
is contributing to the source flux.

A faint galaxy (r~24) is detected 2.1" southeast of the afterglow and
another is 3.0" to the southwest. For a redshift of 2.43 and a standard
cosmology, the projected distances from the afterglow are 17 kpc and
24 kpc. These galaxies may be the source of the two foreground absorption
line systems observed in the afterglow spectrum (Vreeswijk et al., GCN
7391).


The LBT is an international collaboration among institutions in the
United States, Italy and Germany. The LBT Corporation partners are:
*  The University of Arizona on behalf of the Arizona university system
*  Istituto Nazionale di Astrofisica, Italy
*  LBT Beteiligungsgesellschaft, Germany, representing the Max Planck
Society, the Astrophysical Institute Potsdam, and Heidelberg University
*  The Ohio State University
*  The Research Corporation, on behalf of The University of Notre Dame,
University of Minnesota and University of Virginia

This message may be cited.


GRB_name: GRB080325A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7524
SUBJECT: GRB 080325: Subaru detection of NIR afterglow candidate
DATE:    08/03/27 06:50:55 GMT
FROM:    Nobuyuki Kawai at Tokyo Tech  <nkawai@hp.phys.titech.ac.jp>

I. Tanaka, T.-S. Pyo, T. Hattori, K. Aoki (Subaru, NAOJ), C. Tokoku,
T. Yamada (Tohoku U), K. Ohta (Kyoto U), and N. Kawai (Tokyo Tech)
report on behalf of the Subaru GRB team:

We observed the field of GRB 080325 (Vetere et al., GCN 7512) with
MOIRCS on the Subaru Telescope in J and Ks bands starting at 12:51 UT,
March 25, about 8.7 hours after the trigger.  The observation lasted
until 15:43 UT with effective exposures of 18 min in J band and 80 min
in Ks band.  We detected a faint extended object (Ks=19.5) in the
enhanced Swift XRT error circle (Osborne et al., GCN 7513).  We
measure the coordinates of its center as:

18:31:34.24 +36:31:24.3 (J2000, uncertainty 0".3).

There seemed to be a bright spot at the north end of this object.

We performed another set of observation with MOIRCS at March
26.5-26.7 in Ks and J bands.  We confirmed that the north spot of the
source had faded significantly, and the total magnitude of the source
had faded by 0.5 mag.

Based on the positional coincidence and the fading behavior, we
suggest that the faint extended source is the host galaxy of GRB
080325, and the spot in the north was the afterglow.

The source 6" south of the enhanced Swift-XRT error circle reported by
Updike et al. (GCN 7515) was also present in our image, and we measure
its magnitude at ~14:00 UT, March 25 (10 hours after the trigger) as:

J = 18.62 +/- 0.03,

consistent with the magnitude reported by Clemens et al. (GCN 7520).  
Thus it is not likely to be the afterglow of the GRB.


GRB_name: GRB080328A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7525
SUBJECT: GRB 080328: Swift detection of a burst with an optical counterpart
DATE:    08/03/28 08:28:44 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

M. Perri (ASDC), D. N. Burrows (PSU), S. Campana (INAF-OAB),
P. A. Evans (U Leicester), N. Gehrels (NASA/GSFC),
C. Guidorzi (INAF-OAB), C. B. Markwardt (CRESST/GSFC/UMD),
K. L. Page (U Leicester), D. M. Palmer (LANL),
D. Perez (U Leicester), P. Romano (INAF-IASFPA),
R. L. C. Starling (U Leicester), G. Stratta (ASDC),
D. E. Vanden Berk (PSU), P. A. Ward (MSSL-UCL) and
H. Ziaeepour (UCL-MSSL) report on behalf of the Swift Team:

At 08:03:04 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 080328 (trigger=307931).  Swift slewed immediately to the 
burst.  The BAT on-board calculated location is 
RA, Dec 80.479, +47.524 which is 
   RA(J2000) = 05h 21m 55s
   Dec(J2000) = +47d 31' 26"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a multi-peaked
structure with a duration of about 110 sec.  The peak count rate
was ~9500 counts/sec (15-350 keV), at ~10 sec after the trigger. 

The XRT began observing the field at 08:04:44.0 UT, 99.4 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
fading, uncatalogued X-ray source with an enhanced position: RA, Dec
80.48189, 47.51035 which is equivalent to:
   RA(J2000)  = 05h 21m 55.65s
   Dec(J2000) = +47d 30' 37.3"
with an uncertainty of 2.6 arcseconds (radius, 90% containment). This
location is 49 arcseconds from the BAT onboard position, within the BAT
error circle. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of
3.38e+21 cm^-2 (Kalberla et al. 2005), so we cannot constrain the
redshift at this time using the relation from Grupe et al. (2007). A
summary of the promptly downlinked data is given at
http://www.swift.ac.uk/sper/307931/. 

The initial flux in the 2.5 s image was 1.08e-08 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of nominal 400 seconds with the V filter
starting 216 seconds after the BAT trigger. There is a candidate afterglow in
the list of sources generated on-board at
  RA(J2000)  = 05:21:55.85 =  80.4827
  DEC(J2000) = +47:30:39.2  =  47.5109
with a 1-sigma error radius of about 0.6 arc sec. This position is 2.8 arc sec. 
from the center of the XRT error circle. The estimated magnitude is 17.7 with a
1-sigma error of about 0.5 mag. No correction has been made for the expected
extinction of about 1.9 magnitudes. 

Burst Advocate for this burst is M. Perri (perri AT asdc.asi.it). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB080328A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7526
SUBJECT: GRB080328: Faulkes Telescope North observations
DATE:    08/03/28 09:39:11 GMT
FROM:    Cristiano Guidorzi at INAF-OAB  <cristiano.guidorzi@brera.inaf.it>

C. Guidorzi (INAF-OAB),, A. Gomboc (U. Ljubljana), D. Bersier, C.G. 
Mundell, I.A. Steele, R.J. Smith, D. Carter, S. Kobayashi, M. Bode 
(Liverpool JMU), P. O'Brien, N. Bannister, N. Tanvir (U. Leicester) 
report:

The 2-m Faulkes North Telescope (Hawaii) automatically reacted to the
Swift burst GRB080328 (trigger=307931, Perri et al. GCN 7525).

Observations started about 167 s after the trigger time. We confirm
the detection of the optical counterpart by UVOT.

From the first 3x10 s exposure frames in R, we estimate a temporal
decay index between 167 and 240 s after the trigger time of
alpha = 1.4 +/- 0.2.

Filter  Tstart(s)  Exposure(s)    Mag
-----------------------------------------------
    R       167           10      16.96 +/- 0.02
    R       198           10      17.26 +/- 0.02
    R       230           10      17.44 +/- 0.02
-----------------------------------------------

Magnitudes are calibrated with respect to USNOB1 R2 in the R filter.
A systematic error on absolute magnitudes of ~0.3 must be included.


GRB_name: GRB080328A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7527
SUBJECT: GRB 080328: Enhanced Swift-XRT position
DATE:    08/03/28 11:00:29 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 855 s of overlapping XRT Photon Counting mode and UVOT
data for GRB 080328, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 80.48231, +47.51063 which is equivalent
to:

RA (J2000): 05h 21m 55.75s
Dec (J2000): +47d 30' 38.3"

with an uncertainty of 1.7 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest position
can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is
described by Goad et al. (2007, A&A, 476, 1401
http://www.swift.ac.uk/xrt_positions/Goad.pdf), the current algorithm is an
extension of this method.

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB080319B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7528
SUBJECT: GRB080319B, BVRcIc field calibration
DATE:    08/03/28 12:39:47 GMT
FROM:    Arne A. Henden at AAVSO  <arne@aavso.org>

A. Henden (AAVSO) reports:

While the field of GRB080319B has been observed by SDSS, we have also
obtained a four-night BVRcIc field calibration using the 35cm robotic
telescope at Sonoita Research Observatory.  The calibration file
has a limiting magnitude around V=16, with good standards brighter
than V=11 or so.  The file is available at
ftp://ftp.aavso.org/public/calib/grb/grb080319b.dat

This calibration is based on numerous Landolt standards, and has
an external zeropoint error of about 0.02mag. We are continuing
calibration of this field, moving to the west to pick up the
9th magnitude star SAO 64192, and will extend the calibration
file when that photometry is available.  Our system is available
for any other bright BVRI calibrations (4<V<19) for this field or any
other field; contact the author for such requests.

The AAVSO thanks the Curry Foundation for their continued support of the
AAVSO International High Energy Network.


GRB_name: GRB080325A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7529
SUBJECT: GRB080325 - I and z-band Imaging
DATE:    08/03/28 15:27:18 GMT
FROM:    Myungshin Im at Seoul Nat U  <mim@astro.snu.ac.kr>

M. Im, I. Lee (Seoul National Univ), and Y. Urata (Saitama U/ASIAA)
on behalf of EAFON team.

   We took a series of I-band and z-band images of GRB080325,
  using the 1.0m telescope at Mt. Lemmon (Arizona, US)
  operated by the Korea Astronomy Space Science Institute.
   The z-band observation started at March 27, 08:46:06 UT
  (2.19223 days after the burst) and the I-band observation
  started at March 27, 10:41:05 UT (2.27208 days after the burst).

   We do not find an optical counterpart at the location of
  the NIR afterglow candidate reported by Tanaka et al. (GCN 7524),
  in both I and z-band stacked images.
   We set the limit of the GRB afterglow as I > 21.2 mag (3-sigma),
  calibrated with a USNO-B star at (18:31:36.3, 36:31:51.0).

   The afterglow candidate reported by Updike et al. (GCN 7515)
  is detected at both I- and z-bands, with the I-band magnitude
  of I=19.0 +- 0.1 mag, calibrated with the same star as above.
   However, we note that this object is also visible in the DSS
  image (POSS-II), and therefore it is unlikely to be a GRB afterglow.

   We thank the LOAO operator, I. Baek for her assistance for this
  observation.


GRB_name: GRB080328A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7530
SUBJECT: Swift/UVOT observations of GRB080328
DATE:    08/03/28 17:49:09 GMT
FROM:    Paul Ward at MSSL  <paw@mssl.ucl.ac.uk>

P. Ward (MSSL-UCL), P. Schady (MSSL-UCL) and M. Perri (ASDC) report on  
behalf of the Swift-UVOT team

The Swift/UVOT observed the field of GRB 080328 starting 110s after  
the BAT trigger (Perri et al., GCN 7525). The afterglow is detected at

RA:      05h 21m 55.87s
DEC:  +47d 30' 39.4"

only in the white and v filters, with an error radius of 0.6 arcsec  
(90% confidence).
The afterglow is seen to decay in both these filters, and has the  
following magnitudes and 3-sigma upper limits (in the UVOT photometric  
system, Poole et al. (2008, MNRAS, 383, 627)).

Filter Tstart(s)  Exp(s)  Magnitude

white 110  99.8 17.84 +/- 0.05
white 867  99.8 20.43 +/- 0.27
white 5611 399.8 > 21.60
v  217  399.8 17.90 +/- 0.08
v  973  399.8 19.25 +/- 0.20
v  6023 399.8 > 20.00  

The afterglow is not detected in any other filters, perhaps due to the  
high Galactic extinction value of  E(B-V) = 0.58 mag. The following  
are the 3-sigma upper limits for these filters.

Filter Tstart(s)  Exp(s)  Magnitude

b  851  493.6      > 20.96
u   673  338.5    > 20.59
uvw1 648  362.8   > 20.54
uvm2 623  393.2 > 20.38
uvw2 728  498.5   > 20.88

The values quoted above are not corrected for Galactic extinction  
corresponding to a reddening of E(B-V) = 0.58 mag in the direction of  
the burst (Schlegel et al. 1998).


GRB_name: GRB080325A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7531
SUBJECT: GRB 080325, Swift-BAT refined analysis
DATE:    08/03/28 18:08:58 GMT
FROM:    Craig Markwardt at NASA/GSFC/UMD  <craigm@milkyway.gsfc.nasa.gov>

E. Fenimore (LANL), S. D. Barthelmy (GSFC), J. Cummings (GSFC/UMBC),
N. Gehrels (GSFC), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD),
K. McLean (GSFC/UMD), D. Palmer (LANL), A. Parsons (GSFC),
T. Sakamoto (GSFC/UMBC), G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU),
J. Tueller (GSFC), T. Ukwatta (GWU), (i.e. the Swift-BAT team), and
L. Vetere (PSU):

Using the data set from T-323 to T+963 sec from all of the telemetry,
we report further analysis of BAT GRB 080325 (trigger #307604)
(Vetere, et al., GCN Circ. 7512).  The BAT ground-calculated position
is RA, Dec = 277.906, 36.516 deg which is
    RA(J2000)  =  18h 31m 37.5s
    Dec(J2000) = +36d 30' 57.9"
with an uncertainty of 2.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 10%.

The mask weighted light curve has a broad FRED-like structure, with
a rise to peak within ~20 sec, followed by a gradual decay extending
out to T+200 sec. The low partial coding in the initial part of the
burst makes it difficult to distinguish between statistical and real
fluctuations.  T90 (15-350 keV) is 128.4 +- 34.2 sec (estimated
error including systematics).

The time-averaged spectrum from T-29.3 to T+170.5 sec is best fit by a
simple power-law model.  The power law index of the time-averaged
spectrum is 1.68 +- 0.17.  The fluence in the 15-150 keV band is
4.9 +- 0.4 x 10^-06 erg/cm2. The 1-sec peak photon flux measured from
T+38.02 sec in the 15-150 keV band is 1.4 +- 0.6 ph/cm2/sec.  All the
quoted errors are at the 90% confidence level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/307604/BA/


GRB_name: GRB080328A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7532
SUBJECT: GRB 080328: Swift XRT refined analysis
DATE:    08/03/28 19:06:57 GMT
FROM:    Matteo Perri at ISAC/ASDC  <perri@asdc.asi.it>

M. Perri and G. Stratta (ASDC) report on behalf of the Swift XRT team:

We have analysed the first 3 orbits of Swift XRT data of the BAT GRB
080328 (Perri et al., GCN Circ. 7525). The data consist of 151 s in
Windowed Timing (WT) mode, from  T+108s to T+259s, and of
6.9 ks in Photon Counting (PC) mode thereafter.

The best XRT position is the UVOT-enhanced position reported by
Beardmore et al. (GCN Circ. 7527).

The early 0.3-10 keV X-ray light curve in WT mode shows a rapid decay.
Starting from T+260s up to T+13.7ks the curve is well fit by a broken
power-law model with decay indices alpha1=-0.57 (+0.09) (-0.06),
alpha2=-1.10 (+/-0.05) and a temporal break at (1.7+/-0.3) ks.

The WT X-ray spectrum is well fit by an absorbed power-law model
with a photon index of 2.1 (+/-0.1), a column density of
(4.2+/-0.4)e21 cm**-2 and an average observed 0.3-10 keV flux
of 9.3e-10 erg/cm**2/s. The PC X-ray spectrum during the first orbit,
from  T+260s to T+2106s, is also well fit by an absorbed power-law
model with a photon index of 2.2 (+/-0.1) and a column density of
(5.0+/-0.6)e21 cm**-2. The observed 0.3-10 keV flux for this spectrum
is 1.5e-10 erg/cm**2/s. We note the Galactic column density in the
direction of the source is 3.4e21 cm**-2.

Assuming the X-ray emission continues to decline at the same rate, we
predict a 0.3-10 keV XRT count rate of 0.03 count/s at T+24hr, which
corresponds to an observed 0.3-10 keV flux of about
1.4e-12 erg/cm**2/s.

This circular is an official product of the Swift XRT Team.


GRB_name: GRB080328A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7533
SUBJECT: GRB 080328, Swift-BAT refined analysis
DATE:    08/03/28 21:11:42 GMT
FROM:    Craig Markwardt at NASA/GSFC/UMD  <craigm@milkyway.gsfc.nasa.gov>

H. Krimm (GSFC/USRA), S. D. Barthelmy (GSFC), J. Cummings (GSFC/UMBC),
E. Fenimore (LANL), N. Gehrels (GSFC), C. Markwardt (GSFC/UMD),
K. McLean (GSFC/UMD), D. Palmer (LANL), A. Parsons (GSFC), M. Perri (ASDC),
T. Sakamoto (GSFC/UMBC), G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU),
J. Tueller (GSFC), T. Ukwatta (GWU)
(i.e. the Swift-BAT team):

Using the data set from T-120 to T+183 sec from the recent telemetry
downlink, we report further analysis of BAT GRB 080328 (trigger
#307931) (Perri, et al., GCN Circ. 7525).  The BAT ground-calculated
position is RA, Dec = 80.490, 47.523 deg which is
    RA(J2000)  =  05h 21m 57.7s
    Dec(J2000) = +47d 31' 23.8"
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 37%.

The mask-weighted light curve consists of about about ten major pulses
spread over ~100 sec.  T90 (15-350 keV) is 90.6 +- 1.5 sec (estimated
error including systematics).

The time-averaged spectrum from T-2.2 to T+117.5 sec is best fit by a
simple power-law model.  The power law index of the time-averaged
spectrum is 1.52 +- 0.04.  The fluence in the 15-150 keV band is
9.4 +- 0.2 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from
T+9.3 sec in the 15-150 keV band is 5.5 +- 0.3 ph/cm2/sec.  All the
quoted errors are at the 90% confidence level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/307931/BA/


GRB_name: GRB080328A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7534
SUBJECT: GRB 080328: BTA optical imaging and spectroscopy
DATE:    08/03/29 00:10:31 GMT
FROM:    Alberto Castro-Tirado at Inst.de Astro. de Andalucia  <ajct@iaa.es>

T. A. Fatkhullin, A. S. Moskvitin, V. V. Sokolov (SAO-RAS, Nizhnij Arkhyz), 
A. S. Pozanenko (IKI, Moscow), A. de Ugarte Postigo (ESO, Santiago), M. 
Jelnek, J. Gorosabel and A. J. Castro-Tirado (IAA-CSIC Granada), on 
behalf of a larger collaboration, report:

"Following the detection of GRB 080328 by Swift (Perri et al. GCNC 
7525), we have obtained BVRI imaging and spectroscopy (3800-7500 A) with 
the 6.0m BTA SAO-RAS telescope starting on Mar 28.76 UT  (i.e. 12.4 hr 
after the onset of the event). A faint optical source (with R about 
22.5) consistent with the UVOT position (Ward et al. GCNC 7530) is 
detected in all frames, thus implying an upper limit of about 2.5 for 
the GRB 080328 redshift. Its brightness is not consistent with the 
extrapolation of the early decay reported by Guidorzi et al. (GCNC 7526) 
indicating significant contribution of the reverse shock emission in the 
FTN data. Our BTA spectrum (2 x 900s) shows only a faint continuum and 
nothing conclusive can be reported (except the non-existence of strong 
emission lines arising from an underlying host galaxy)."

This message can be quoted.

[GCN OPS NOTE(29mar08): Per author's request, 3 typos were fixed
in the Fatkhullin, Moskvitin and Pozanenko names.]


GRB_name: GRB080319B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7535
SUBJECT: GRB 080319B: Continued Gemini-South followup and possible host galaxy
DATE:    08/03/29 10:11:00 GMT
FROM:    Daniel Perley at U.C. Berkeley  <dperley@astro.berkeley.edu>

D. A. Perley, J. S. Bloom (UC Berkeley) and H.-W. Chen (U Chicago) report:

We have continued to monitor the optical afterglow of GRB 080319B from 
Gemini-South.  Additional images were taken on UT March 21, 25, and 28. 
  Despite the presence of the Moon and low elevation of the target, the 
afterglow remains detected in all filters.  We report on photometry, 
calibrated to SDSS DR6, as follows (including an improved analysis of 
images obtained on UT March 20, previously reported in GCN 7486).

t(hr)  filt mag   err
24.808  g   20.83 0.05
25.099  r   20.53 0.02
25.363  i   20.37 0.03
25.686  z   20.32 0.04

48.653  r   21.56 0.03

144.553 g   23.59 0.15
144.886 r   23.49 0.09
145.220 i   23.13 0.06
145.553 z   23.48 0.11

216.703 r   23.56 0.06
217.036 i   23.28 0.06

The object appears visibly extended at late times, with a possible 
projection extending to the south; this may be the host galaxy of this 
gamma-ray burst.  The imaging was acquired under variable seeing 
conditions and we caution that the presence of an underlying host may 
complicate the photometry.

While roughly consistent with simple power-law decay of alpha=1.2-1.3 
(e.g. GCN 7438, Li et al.), in detail the observations deviate slightly 
from a simple power-law, including a flattening in the last two sets of 
observations that may be due host galaxy light (and possibly a small 
amount of supernova contribution.)

In addition, we note the presence of a very red source at an offset of 
2.65" (slightly west of south) from the afterglow.  Preliminary 
photometry of this object gives the following:

g = 24.3  +/- 0.2  (marginal detection)
r = 23.76 +/- 0.06
i = 22.55 +/- 0.03
z = 21.71 +/- 0.03

This offset corresponds to 21 kpc at a redshift of 0.937 (Vreeswijk et 
al., GCN 7451).  It is dominated by a bright PSF-like center but also is 
visibly extended to the south.  It may be an intervening absorber.

Further follow-up is planned and encouraged.


GRB_name: GRB080330A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7536
SUBJECT: GRB 080330: TAROT Calern observatory optical detection
DATE:    08/03/30 04:02:13 GMT
FROM:    Alain Klotz at CESR-CNRS  <Alain.Klotz@free.fr>

Klotz, A. (CESR-OMP), Boer M. (OHP), Atteia J.L. (LATT-OMP) report:

We imaged the field of GRB 080330 detected by SWIFT
(trigger 308041) with the TAROT robotic telescope (D=25cm)
located at the Calern observatory, France.

The observations started 20.4s after the GRB trigger
(4.5s after the notice). The elevation of the field decreased from
from 26 degrees above horizon and weather conditions
were good.

We detect a new raising source in the error box given by SWIFT
We detected the candidate couterpart in the XRT location
at the following position (+/- 1 arcsec):

RA(J2000) = 11h 17m 04s47
DEC(J2000) +30d 37' 26"90

OT was R~16.8 at 300s after GRB.

Magnitudes were estimated with the nearby USNO-B1 stars
and are not corrected for galactic dust extinction.

N.B. Galactic coordinates are lon=197.8461 lat=+69.1207
and the galactic extinction in R band is 0.0 magnitudes
estimated from D. Schlegel et al. 1998ApJ...500..525S.

This me


GRB_name: GRB080330A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7537
SUBJECT: GRB 080330: Swift detection of a burst with an optical counterpart
DATE:    08/03/30 04:02:22 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

J. Mao (INAF-OAB), W. H. Baumgartner (GSFC/UMBC), D. N. Burrows (PSU),
N. Gehrels (NASA/GSFC), S. T. Holland (CRESST/USRA/GSFC),
J. A. Kennea (PSU), K. M. McLean (GSFC/UMD), D. M. Palmer (LANL),
A. M. Parsons (GSFC), M. Stamatikos (NASA/ORAU),
R. L. C. Starling (U Leicester), T. N. Ukwatta (GSFC/GWU) and
D. E. Vanden Berk (PSU) report on behalf of the Swift Team:

At 03:41:16 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 080330 (trigger=308041).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 169.302, +30.570 which is 
   RA(J2000) = 11h 17m 12s
   Dec(J2000) = +30d 34' 13"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a multiple-peak
structure with a duration of about 60 sec.  The peak count rate
was ~1500 counts/sec (15-350 keV), at ~0 sec after the trigger. 


The XRT began observing the field at 03:42:27.4 UT, 70.5 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
fading, uncatalogued X-ray source located at RA, Dec 169.26095,
30.62298 which is equivalent to:
   RA(J2000)  = 11h 17m 2.63s
   Dec(J2000) = +30d 37' 22.7"
with an uncertainty of 3.077 arcseconds (radius, 90% containment). This
location is 229 arcseconds from the BAT onboard position, outside the
BAT error circle. 

A power-law fit to a spectrum formed from promptly downlinked event
data does not constrain the column density, so we cannot provide limits
on the redshift using spectroscopy and the relation from Grupe et al. 
(2007). A summary of the promptly downlinked data is given at
http://www.swift.ac.uk/sper/308041/. 

The initial flux in the 2.5 s image was 2.03e-09 erg cm^-2 s^-1 (0.2-10
keV). 


UVOT took a finding chart exposure of nominal 100 seconds with the White
(160-650 nm) filter starting 82 seconds after the BAT trigger. There is a
candidate afterglow in the list of sources generated on-board at
  RA(J2000)  = 11:17:04.51 = 169.2688
  DEC(J2000) = +30:37:22.1  =  30.6228
with a 1-sigma error radius of about 1.0 arc sec. This position is 6.1 arc sec. 
from the center of the XRT error circle. The estimated magnitude is 18.8 with a
1-sigma error of about 0.5 mag. No correction has been made for the expected
extinction corresponding to E(B-V) of 0.02. 




Burst Advocate for this burst is J. Mao (jirong.mao AT brera.inaf.it). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB080330A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7538
SUBJECT: GRB 080330A: ROTSE-III Detection of Optical Counterpart
DATE:    08/03/30 04:04:25 GMT
FROM:    Brad Schaefer at LSU  <schaefer@grb.phys.lsu.edu>

B. E. Schaefer (Louisiana State) and T. Guver (U Istanbul) report on
behalf of the ROTSE collaboration:

ROTSE-IIIb, located at McDonald Observatory, Texas, responded to GRB 
080330A (Swift trigger 308041). The first image was at 03:41:39.2 UT, 22.4 
s after the burst (7.2 s after the GCN notice time). The unfiltered images 
are calibrated relative to USNO A2.0. We detect a new object, not visible 
in the DSS (second epoch), with coordinates:

     11:17:04.5 +30:37:24.0 (J2000), 

with positional uncertainty of 1" or better.  This is inside the XRT error
box.  The object is roughly 17.5 magnitude, and it declined immediately
only to rise again to a peak at 16.9 mag roughly ~300 seconds after the
burst.  A jpeg image is available at
http://www.rotse.net/images/gsb308041_3b00_img.jpg

Continuing observations are in progress. 


GRB_name: GRB080330A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7539
SUBJECT: GRB 080330: Liverpool Telescope Optical observations
DATE:    08/03/30 04:21:17 GMT
FROM:    Andreja Gomboc at LT,ARI,Liverpool JMU  <ag@astro.livjm.ac.uk>

A. Gomboc (University of Ljubljana), C. Guidorzi (U. Bicocca & INAF-OAB), 
A. Melandri, C. G. Mundell, A. Monfardini, R.J. Smith, I.A. Steele,D. 
Bersier, S. Kobayashi, M. Burgdorf, D. Carter (Liverpool JMU) report:

The 2-m Liverpool Telescope reacted robotically to GRB 080330 (Swift 
trigger 308041) starting 3 min after the GRB trigger time. We detect 
initially rising and subsequently fading optical candidate in r', i' and 
g' filters at the posotion consistent with XRT source, UVOT (Mao et al., 
GCN 7537) and TAROT optical candidate (Klotz, Boer & Atteia, GCN 7536).

The magnitude of the source in first frames is r'=17.3 +-0.1.


GRB_name: GRB080330A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7540
SUBJECT: GRB080330 - SDSS Pre-Burst Observations
DATE:    08/03/30 04:24:11 GMT
FROM:    Richard J. Cool at U.of AZ/Steward Obs  <rcool@as.arizona.edu>

Richard J. Cool (Arizona), Daniel J. Eisenstein (Arizona),
David W. Hogg (NYU), Michael R. Blanton (NYU), David J. Schlegel
(LBNL), J. Brinkmann (APO), Donald Q. Lamb (Chicago), Donald
P. Schneider (PSU), and Daniel E. Vanden Berk (PSU) report:

The Sloan Digital Sky Survey (SDSS) imaged the field of burst
GRB080330 prior to the burst.  As these data should be useful
as a pre-burst comparison and for calibrating photometry,
we are supplying the images and photometry measurements for
this GRB field to the community.

Data from the SDSS, including 5 FITS images, 3 JPGS, and
3 files of photometry and astrometry, are being placed at
http://mizar.as.arizona.edu/~grb/public/GRB080330

We supply FITS images in each of the 5 SDSS bands of a 8'x8'
region centered on the GRB position (ra=169.302 (11:17:12.5),
dec=30.5700 (30:34:12.0); Swift-BAT 308041), as well as 3 gri
color-composite JPGs (with different stretches). The units
in the FITS images are nanomaggies per pixel.  A pixel is
0.396 arcsec on a side. A nanomaggie is a flux-density unit
equal to 10^-9 of a magnitude 0 source or, to the extent that
SDSS is an AB system, 3.631e-6 Jy.  The FITS images have WCS
astrometric information.

In the file GRB080330_sdss.calstar.dat, we report photometry
and astrometry of 219 bright stars (r<20.5) within 15' of the
burst location.  The magnitudes presented in this file are asinh
magnitudes as are standard in the SDSS (Lupton 1999, AJ, 118,
1406). Beware that some of these stars are not well-detected
in the u-band; use the errors and object flags to monitor
data quality.

In the files GRB080330_sdss.objects_flux.dat and
GRB080330_sdss.objects_magnitudes.dat, we report photometry
of 1512 objects detected within 6' of the GRB position.
We have removed saturated objects and objects with model
magnitudes fainter than 23.0 in the r-band.  The fluxes listed
in GRB080330_sdss.objects_flux.dat are in nanomaggies while
the magnitudes listed in GRB080330_sdss.objects_magnitudes.dat
are asinh magnitudes.


All quantities reported are standard SDSS photometry, meaning
that they are very close to AB zeropoints and magnitudes are
quoted in asinh magnitudes.  Photometric zeropoints are known
to about 2% rms.  None of the photometry is corrected for
dust extinction.  The Schlegel, Finkbeiner, and Davis (1998)
predictions for this region are A_U=0.082 mag, A_g=0.060 mag,
A_r = 0.044 mag, A_i=0.033 mag, and A_z=0.023 mag.

The file GRB080330_sdss.spectro.dat contains a list of the
2 objects with SDSS spectroscopy within 6 arcminutes of the
GRB position.  In addition to the redshift and 1-sigma error
for each object, this file also lists the object spectroscopic
classification.


SDSS astrometry is generally better than 0.1 arcsecond per
coordinate.  Users requiring high precision astrometry should
take note that the SDSS astrometric system can differ from
other systems such as those used in other notices; we have
not checked the offsets in this region.

More detailed information pertaining to our SDSS GRB releases
can be found in our initial data release paper (Cool et
al. 2006, PASP 118, 733).  See the SDSS DR4 documentation for
more details: http://www.sdss.org/dr5.

These data have been reduced using a slightly different
pipeline than that used for SDSS public data releases.
We cannot guarantee that the values here will exactly match
those in the data release in which these data are included.
In particular, we expect the photometric calibrations to differ
by of order 0.01 mag.

This note may be cited, but please also cite the SDSS data
release paper, Adelman-McCarthy et al. (2007, ApJS, 172, 634),
when using the data or referring to the technical documentation.


GRB_name: GRB080330A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7541
SUBJECT: GRB 080330: error in reported XRT position
DATE:    08/03/30 04:36:19 GMT
FROM:    David Burrows at PSU/Swift  <dnburrows@gmail.com>

D. N. Burrows (PSU) reports on behalf of the Swift XRT team:

The XRT position for GRB 080330 that was distributed in GCN Circ. 
7537 was incorrect.   The initial on-board XRT position determined 
immediately after the spacecraft slew was

GRB_RA:          169.2707d {+11h 17m 04.9s} (J2000),
GRB_DEC:         +30.6223d {+30d 37' 20.2"} (J2000),

with a nominal error circle radius of 5.0 arcseconds.  This position 
was 6.1 arcseconds from the UVOT position.  It appears that shortly 
after arriving on-target, the spacecraft began slowly drifting 
because the star tracker did not lock properly on the star 
field.  The updated XRT position based on promptly downloaded data 
was determined using inaccurate aspect information from the satellite 
and was therefore incorrect.  We apologize for any confusion that 
this may have caused.  We reiterate that the XRT position appears to 
be consistent with the optical position.


GRB_name: GRB080330A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7542
SUBJECT: GRB 080330A: PAIRITEL Infrared Detections
DATE:    08/03/30 05:22:44 GMT
FROM:    Josh Bloom at UC Berkeley  <jbloom@astron.berkeley.edu>

J. S. Bloom (UC Berkeley) and D. L. Starr (UCB; LCOGT) report:

"We began observing the field of GRB 080330A (Mao et al. GCN 7537) at  
2008-03-30 03:53:24.8 UT with PAIRITEL. In a stack of the first 33  
frames (each 7.8 sec) exposures, consistent with the BAT/XRT/UVOT  
(7537, also Burrows et al. GCN 7541) and groundbased position (7536,  
7539, 7538), we find a point source in JHKs bands. The preliminary  
photometry yields:

# t (MJD)       terr (day)      filt     mag     merr
54555.164606    0.001499        h       15.33       0.04
54555.164606    0.001499        k       14.59       0.04
54555.164606    0.001499        j        16.00       0.04

We find a position relative to 2MASS of (700 mas rms uncertainty):
     ra = 11:17:04.496  dec = +30:37:23.53 J2000

Observations are ongoing."


GRB_name: GRB080330A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7543
SUBJECT: GRB 080330: TAROT Calern observatory optical observations
DATE:    08/03/30 06:31:40 GMT
FROM:    Alain Klotz at CESR-CNRS  <Alain.Klotz@free.fr>

Klotz, A. (CESR-OMP), Boer M. (OHP), Atteia J.L. (LATT-OMP) report:

We complete the TAROT analysis of GRB 080330 detected by SWIFT
(trigger 308041) at the location of the rising afterglow
detected by Klotz et al. (GCNC 7536). We refined the
coordinates (better than 1 arcsec) :

RA(J2000) = 11h 17m 04s49
DEC(J2000) +30d 37' 23"5

We consider the date of trigger : t0 = 2008-03-30T03:41:17

The first image is trailed with a duration of 60.0s
(see the description in Klotz et al., 2006, A&A 451, L39).
We do not detect the OT with a limiting magnitude of:
t0+20.4s to t0+80.4s : R > 17.0

This limiting magnitude is compatible with the detection
R~17.5 by ROTSE-IIIb (Schaefer et Guver GCNC 7538) at
~t0+25s.

The later images, in tracking mode, show the afterglow.
We measured the alpha index considering flat flux is
proportional to t^-alpha:

t0+ 88s to t0+ 332s : alpha=-0.8 (rise)
t0+332s to t0+ 428s : maximum of brightness R~16.8
t0+428s to t0+1068s : alpha=+0.4 (decay)
t0+1068s : R~17.2

Two images were taken between t0+1177s
and t0+1363s during the dawn. They seem to show
a plateau or even a rebrightening.
Observations are now stoped at Calern.

This message may be cited.


GRB_name: GRB080330A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7544
SUBJECT: GRB 080330: NOT redshift
DATE:    08/03/30 07:19:56 GMT
FROM:    Daniele Malesani at Niels Bohr Inst,Dark Cosmology Center  <malesani@astro.ku.dk>

Daniele Malesani, Johan P.U. Fynbo (DARK), Pall Jakobsson (Univ. 
Hertfordshire), Paul M. Vreeswijk (DARK), Sami-Matias Niemi (NOT), 
report on behalf of a larger observation:

We observed the afterglow of GRB 080330 (Mao et al., GCN 7537) with the 
NOT equipped with ALFOSC. We clealy detect the optical counterpart 
(Klotz et al., GCN 7536; Mao et al., GCN 7537, Schaefer & Guver, GCN 
7538; Gomboc et al., GCN 7539; Bloom & Starr, GCN 7542). We measure R = 
17.55 on March 30.17596 UT (32.1 min after the GRB), assuming R = 17.61 
for the USNO star 1206-0188558 at RA = 11:16:57.541, Dec = +30:37:51.51.

A 1800 s spectrum with ALFOSC was acquired starting 46 min after the 
GRB, covering the range 3700-8000 AA. A preliminary reduction of the 
data reveals absorption features in the spectrum from C IV, Zn II, Fe 
II, and Mg II at redshift z=1.51.

We acknowledge excellent support from the NOT staff


GRB_name: GRB080330A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7545
SUBJECT: GRB 080330: GROND Observations
DATE:    08/03/30 10:06:42 GMT
FROM:    Christian Clemens at MPE  <cclemens@mpe.mpg.de>

C. Clemens, A. Kupcu Yoldas, J. Greiner, A. Yoldas, T. Kruehler (all MPE 
Garching) and G. Szokoly (Eoetvoes Univ., Budapest and MPE Garching) report 
on behalf of the GROND team:

We observed the field of GRB 080330 (Swift trigger 308041; Mao et al., GCN 
#7537) simultaneously in g', r', i', z', J, H and K with GROND (Greiner et 
al. 2008, PASP) mounted at the 2.2m ESO/MPI telescope at La Silla Observatory 
(Chile).

Observations started at 03:44:23 UT on March, 30th, 2008, about 3.1 mins after 
the GRB trigger. We found a bright point source at

RA (J2000) = 11h 17m 04.48s
DEC (J2000) = 30d 37' 24.4'',

coincident with the optical afterglow first reported by Klotz et al. (GCN 
#7536 and #7543).

Based on the first 240 s of effective exposures in J and H, we estimate 
magnitudes of

J=15.92 +/- 0.02 and H=15.45 +/- 0.01,

calibrated against 2MASS stars.


GRB_name: GRB080330A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7546
SUBJECT: GRB080330: LOAO R-band Detection
DATE:    08/03/30 12:06:18 GMT
FROM:    Myungshin Im at Seoul Nat U  <mim@astro.snu.ac.kr>

M. Im, I. Lee (Seoul National Univ.), Y. Urata (Saitama U/ASIAA),
J.W. Lee, J. Yoon, S.-L. Kim, C.-U. Lee (KASI), on behalf of EAFON team.

   We took R-band images of GRB080330 (Hao et al. GCN 7537)
  using the 1.0m telescope at Mt. Lemmon (Arizona, US)
  operated by the Korea Astronomy Space Science Institute.
   The R-band imaging started at March 30, 06:57:55.1 UT
  (3:15:56 after the burst).

    We clearly detect the afterglow at the location reported by
  Schaefer et al. (GCN 7538).

      Start time         Mid-point                Rmag
  -------------------------------------------------------------
      06:57:55.1         07:11:50.4           19.63 +- 0.05
  (3hr15m after burst) (3hr30m after burst)

  The magnitude is calibrated with a GSC2.2 star at
  (11:16:56.54, +30:37:51.4).
  The afterglow faded by more than 2 magnitudes since the
  detections shoftly after the burst (GCN 7536, 7538, 7543).

   This message may be cited.


GRB_name: GRB080330A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7547
SUBJECT: GRB 080330: Redshift Confirmation from Hobby-Eberly Telescope Spectroscopy
DATE:    08/03/30 15:21:39 GMT
FROM:    Antonino Cucchiara at PSU  <cucchiara@astro.psu.edu>

A. Cucchiara & D. B. Fox (PSU) report on behalf of a larger
collaboration:

"Starting on 2008 March 30.35 UT we used the Marcario LRS spectrograph
on the Hobby-Eberly Telescope (R ~ 230 ) to obtain 2 x 1000s spectra
of the optical afterglow (Mao et al., GCN 7537) of GRB 080330. The
spectrum covers the wavelength range 4100 to 10,500 Angstrom. We
observe multiple metal absorption features including the MgII doublet
(2796, 2803 A) and MgI (2852 A), FeII (2586, 2600 A), ZnII (2026 A)
and NiII (1741,1751 A) at redshift z = 1.51.  Our observations are
consistent with the redshift and features reported by Malesani et
al. (GCN 7544)."


GRB_name: GRB080328A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7548
SUBJECT: Konus-Wind observation of GRB 080328
DATE:    08/03/30 15:58:08 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val@mail.ioffe.ru>

S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks,
and T. Cline on behalf of the Konus-Wind team report:

The long GRB 080328 (Swift-BAT trigger #307931: Perri et al., GCN
7525, Krimm et al., GCN 7533)
triggered Konus-Wind at T0=28982.306 s UT (08:03:02.306).

The burst light curve shows a multipeaked structure
with a total duration of ~90 s.

As observed by Konus-Wind the burst
had a fluence of 2.23(-0.22, +0.23)x10^-5 erg/cm2,
and a 256-ms peak flux measured from T0+10.512 s
of (2.51 +/- 0.41)x10^-6 erg/cm2/s
(both in the 20 keV - 1 MeV energy range).

The time-integrated spectrum of the burst
(from T0 to T0+90.368 s) is well fitted (in the 20 keV-1 MeV range)
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with alpha = -1.13(-0.20, +0.17),
and Ep = 289(-57, +93) keV (chi2 = 62.8/56 dof).

The spectrum of the most intense part (from T0+8.448 to T0+16.640 s)
is well fitted (in the same range)
by a power law with exponential cutoff model
with alpha =  -0.59(-0.19, +0.17)
and Ep = 338(-40, +51) keV (chi2 = 60.8/56 dof).
The fluence of this part is (8.79 +/- 0.68)x10^-6 erg/cm2.

All the quoted errors are at the 90% confidence level.

The Konus-Wind light curve of this GRB is available
at http://www.ioffe.rssi.ru/LEA/GRBs/GRB080328_T28982/


GRB_name: GRB080330A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7549
SUBJECT: GRB 080330, Swift-BAT refined analysis
DATE:    08/03/30 16:39:37 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

C. Markwardt (GSFC/UMD), S. D. Barthelmy (GSFC), J. Cummings (GSFC/UMBC),
E. Fenimore (LANL), N. Gehrels (GSFC), H. Krimm (GSFC/USRA),
J. Mao (INAF-OAB), K. McLean (GSFC/UMD), D. Palmer (LANL),
A. Parsons (GSFC), T. Sakamoto (GSFC/UMBC), G. Sato (GSFC/ISAS),
M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-240 to T+963 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 080330 (trigger #308041)
(Mao, et al., GCN Circ. 7537).  The BAT ground-calculated position is
RA, Dec = 169.278, 30.607 deg, which is 
   RA(J2000)  =  11h 17m 06.7s 
   Dec(J2000) = +30d 36' 24.1" 
with an uncertainty of 1.8 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 53%.
 
The mask-weighted light curve shows an initial set of 3 overlapping peaks
(the brightest first) starting at ~T_zero, and the 3rd ending at ~T+15 sec,
then it returns to baseline.  A 4th peak starts at roughly T+50 sec and
ends at roughly T+70 sec.  T90 (15-350 keV) is 61 +- 9 sec
(estimated error including systematics).
 
The time-averaged spectrum from T-0.5 to T+71.9 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
2.53 +- 0.45.  The fluence in the 15-150 keV band is 3.4 +- 0.8 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+0.44 sec in the 15-150 keV band
is 0.9 +- 0.2 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/308041/BA/
 
We note that the fluence ratio in a simple power-law fit between the
25-50 keV band and the 50-100 keV band is 1.44.  This fluence ratio is larger
than 1.32 which can be achieved in the Band function of alpha=-1.0, beta=-2.5,
and Epeak=30 keV.  Thus, preliminary analysis shows that Epeak of the burst
is very likely around or below 30 keV.  Therefore the burst can be classified
as an X-ray flash (e.g. Sakamoto et al. ApJ in press, arXiv:0801.4319).


GRB_name: GRB080330A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7550
SUBJECT: GRB080330: TNT optical observations
DATE:    08/03/30 16:49:47 GMT
FROM:    L.P. Xin at NAOC  <xlp@bao.ac.cn>

X.F.Wang, J.Z.Li, Q.C.Feng, L.P.Xin, M.Zhai, 
Y.L.Qiu, J.Y.Wei, J.Y.Hu,  J.S.Deng, J.Wang, 
Y.Urata and  W.K.Zheng on behalf of EAFON report:

We have observated the field of GRB080330
(Mao et al. GCN 7537)  in R band with TNT
at Xinglong observatory, the magnitude of afterglow 
derieved from USNO-b1.0 is R=20.4+/-0.2
with the mean time of 9.4hr after the burst.

This message may be cited

For more information about Xinglong GRBs Follow-up 
observations, please visit the website:
http://www.xinglong-naoc.org/grb/


GRB_name: GRB080328A
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7551
SUBJECT: GRB 080328: Suzaku WAM observation of the prompt emission
DATE:    08/03/30 23:10:38 GMT
FROM:    Makoto Tashiro at Saitama U/Swift  <tashiro@phy.saitama-u.ac.jp>

N. Kodaka, M. Tashiro, Y. Terada, Y. Urata, A. Endo,
K. Onda, M. Suzuki, K. Morigami (Saitama U.),
K. Yamaoka, Y. E. Nakagawa, S. Sugita (Aoyama Gakuin U.),
M. Ohno, T. Uehara, T. Takahashi, Y. Fukazawa,
C. Kira, Y. Hanabata (Hiroshima U.), T. Tamagawa (RIKEN),
T. Enoto, R. Miyawaki, K. Nakazawa, K. Makishima (Univ. of Tokyo),
E. Sonoda, M. Yamauchi, H. Tanaka, R. Hara (Univ. of Miyazaki),
M. Kokubun, M. Suzuki, T. Takahashi (ISAS/JAXA), S. Hong (Nihon U.),
on behalf of the Suzaku WAM team, report:

The long GRB 080328 (Swift/BAT trigger #307931 ; Perri et al.,
GCN 7525) was detected by the the Suzaku Wide-band  All-sky Monitor
(WAM) which covers an energy range of 50 keV - 5 MeV at 2008-03-28 
08:03:14 UT (=T0). The observed light curve shows a multi-peaked
structure starting at T0+0s, ending at T0+100 with a duration (T90)
of about 85 seconds. The fluence in 100 - 1000 keV was
1.61 (-0.40,+0.37) * 10^-5 erg/cm^2. The 1-s peak flux measured from
T0+0s was 6.4 (-0.39,+0.39) photons/cm^2/s in the same energy range.

Preliminary result shows that the time-averaged spectrum from T0-0s to
T0+100s is well fitted by a single power-law with a photon index
of 1.72 (-0.26, +0.38) (chi^2/d.o.f = 11.9/15).
All the quoted errors are at statistical 90% confidence level,
in which the systematic uncertainties are not included.

The light curves for this burst are available at:
http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html


GRB_name: GRB080330A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7552
SUBJECT: GRB 080330 Swift-UVOT refined analysis
DATE:    08/03/30 23:28:41 GMT
FROM:    Paul Kuin at MSSL  <npkuin@googlemail.com>

N.P.M. Kuin (MSSL/UCL) and J.Mao (INAF) report on behalf of the
Swift-UVOT team:

The Swift/UVOT started observations of  GRB 080330 (Mao et al,
GCN Circ. 7537) with a settling exposure in the UVOT v-filter
starting 2008-03-30 at 03:42:19 U, 63 seconds after the BAT
trigger, and a finding chart exposure in the white filter starting
83 seconds after the trigger. During the subsequent exposure in the
V filter, starting at 189 seconds after the trigger, the spacecraft
lost lock and drifted. In the V image, a clear trail is visible
that all the stars in the field follow. In other filters, there is
no clear evidence of lost counts, except in one image in b. Those
exposures are short, or have much background (white), which suggest
that only a fraction of the counts is lost.

The extraction of the magnitudes below relies on a 5 aperture
around the source. No counts are visible due to the source outside
the aperture in the images. However, these magnitudes should be
regarded as upper limits until a more detailed reduction can be
done. Based on some tests, the magnitude may be underestimated as
much as 0.7 magnitudes. The v-filter data were extracted using
an aperture closely matching the shape of the trail and were
measured from the event data. There is an uncertainty in this
approach as well, since it is not clear what part of the PSF is
sampled. Therefore the V magnitudes can be over-or underestimated
by 0.25 magnitudes.

The observations start before a peak is reached. In the white filter,
a peak is apparent at T+128 +/- 5 seconds. In the v filter data, two
peaks may be present at T+ 438 and 1038 +/- 25s. It is unlikely that
the satellite drift caused these variations because the aperture
included the whole trail. The uvw1 magnitude has upper limits until quite
late in the burst, and must rise between T+791 and T+1416s. This
is an indication of achromatic evolution in this burst.

Only an upper limit is found in the uvw2 and uvm2 filters,
which is consistent with the reported redshift of 1.51 (Malesani,
et al. GCN 7544, and Cucchiara et al. GCN 7547).

Filter Tstart(s) Tstop(s) Exp(s) Mag     Mag-error [systematic error]

wh         83     183      98    18.2       0.06 [+0.7]
v         189     588     399.8  18.5-17.2  0.3  [+/-0.25] (*)
uvm2      594    1390      58.4 >18.55           (3 sigma UL)
uvw1      619     638      19.5 >18.02           (3 sigma UL)
u         644     664      19.4  17.14      0.16 [+0.7]
b         669     678       9.6  18.9       0.6  [+0.7]
wh        683     693       9.8  17.76      0.14 [+0.7]
uvw2      698     870      38.9 >18.77           (3 sigma UL)
uvw1      772     791      19.8 >18.04           (3 sigma UL)
u         796     815      19.4  16.66      0.17 [+0.7]
b         822     832       9.6  17.66      0.22 [+0.7]
white     836     979     107.8  17.55      0.03 [+0.7]
v         985    1384     400    18.0-17.2  0.3  [+/-0.25] (*)
uvw1     1416    1436      19.4  17.7       0.3  [+0.7]
b        1464    1483      19.8  18.14      0.22 [+0.7]
white    1490    1499       9.6  17.91      0.15 [+0.7]

(*) For the V magnitudes the range is given as seen in the event data.

The values quoted above are not corrected for the expected Galactic
extinction corresponding to a reddening of E_{B-V} = 0.02 mag in the
direction of the burst (Schlegel et al. 1998).


GRB_name: GRB080330A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7553
SUBJECT: GRB 080330, SMARTS optical/IR afterglow observations
DATE:    08/03/31 01:58:36 GMT
FROM:    Bethany Cobb at Yale U  <cobb@astro.yale.edu>

B. E. Cobb (Yale), part of the larger SMARTS consortium, reports:

Using the ANDICAM instrument on the 1.3m telescope at CTIO, we
obtained optical/IR imaging of the error region of GRB 080330
(GCN 7537, Mao et al.), with a mid-exposure time of
2008-03-30 04:17:29 UT, which is ~36 minutes post-burst.
Several dithered images were obtained in each filter,
with total summed exposure times of 180s in each of BRIYJK and
120s in each of H and V.

The GRB afterglow (GCN 7537, Mao et al.) is detected in all our images
with the following magnitudes (which have not been corrected
for Galactic reddening):

B= 18.27 +/- 0.04
V= 17.90 +/- 0.04
R= 17.59 +/- 0.03
I= 17.09 +/- 0.03
J= 16.36 +/- 0.07
H= 15.76 +/- 0.07
K= 15.14 +/- 0.06

Optical photometry is calibrated against Landolt standard stars
and IR photometry is calibrated against the 2MASS star at
coordinates RA/DEC=11:17:03.34 +30:38:31.1.

The afterglow clearly decays between individual images.
In R-band images taken between 20 and 52 minutes post-burst,
the afterglow decays by 0.7 magnitudes, indicating
an approximate decay rate of alpha = -0.7 (where afterglow flux
is proportional to t^alpha).


GRB_name: GRB080330A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7554
SUBJECT: GRB 080330: REM optical observations
DATE:    08/03/31 08:35:23 GMT
FROM:    Paolo D'Avanzo at INAF-OAB  <paolo.davanzo@brera.inaf.it>

P. D'Avanzo, S. Covino, D. Fugazza, L.A. Antonelli, L.  Calzoletti,  S. 
Campana, G.  Chincarini, M.L. Conciatore, S. Cutini, V. D'Elia, F.  
D'Alessio, F.  Fiore, P. Goldoni, D. Guetta,  C. Guidorzi, G.L.  Israel, 
E. Maiorano, N. Masetti, A. Melandri, E. Meurs, L. Nicastro,  E. 
Palazzi, E. Pian, S. Piranomonte, L.  Stella, G.  Stratta, G.  
Tagliaferri, G. Tosti, V.Testa, S.D. Vergani,  F. Vitali report on 
behalf of the REM team:

The robotic 60-cm REM telescope located at La Silla (Chile) observed 
automatically the field of the GRB 080330 (Mao et al., GCN 7537) on 
March 30 03:42:11 UT (about 55 seconds after the burst).

We clearly detect the afterglow reported in GCNs 7536 (Klotz et al.), 
7537 (Mao et al.) 7538 (Schaefer & Guver), 7539 (Gomboc et al.), 7542 
(Bloom & Starr), 7544 (Malesani et al.), 7545 (Clemens et al.), 7546 
(Lee et al.), 7550 (Wang et al.).

The R-band light curve between 70s < t-t0 < 1800s clearly shows an 
initial rising with a maximum around 330s < t-t0 < 450s and a subsequent 
plateau with a possible rebrightening at 900s < t-t0 < 1100s, as noted 
in GCNs 7538 (Schaefer & Guver), 7543 (Klotz et al.) and 7552 (Kuin & Mao).

Further analysis is in progress.


GRB_name: GRB080330A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7555
SUBJECT: GRB080330: Swift XRT refined analysis
DATE:    08/03/31 12:26:12 GMT
FROM:    Jirong Mao at INAF-OAB  <jirong.mao@brera.inaf.it>

GRB080330: Swift XRT refined analysis

 J. Mao, A. Moretti, and C. Guidorzi (INAF-OAB) report on behalf of the Swift-XRT team:
 
We have analysed the Swift-XRT data obtained for BAT GRB 080330 (trigger #308041, Mao et al., GCN Circ. 7537). The data consist of 57 s in Windowed Timing (WT) mode, starting 77s after the BAT trigger and 1.36 ks in Photon Counting (PC) mode. The best X-ray position is given in Burrows GCN 7541.

The XRT light-curve can be fit by a power-law with a slope of alpha1=5.22+/-0.30 up to a break at t=167.9+/-7.3 s, which is followed by a shallow decay with a slope of alpha2=0.20+/-0.07.
 
The spectrum formed from all the WT data can be modeled with a power-law of photon index Gamma=2.03+/-0.09, with the fixed absorbing Galactic column of NH=1.23e20 cm^-2. The spectrum formed from the PC data can be modeled with a power-law of photon index Gamma=1.91 0.09, with an absorbing column of NH=(2.78+/-1.22)e21 cm^-2 (in excess with respect to the Galactic value of 1.23e20 cm^-2).

If the light-curve continues to decay with a slope of 0.20, after 48 hours, the light curve will have count rate of 0.18 count s^-1, corresponding to an observed (unabsorbed) flux of 5.4e-12(1.3e-11) ergcm^-2 s^-1. 

This circular is an official product of the Swift-XRT team.


GRB_name: GRB080330A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7556
SUBJECT: GRB080330: optical observations
DATE:    08/04/01 00:18:24 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

A. Sergeev, M. Andreev (Terskol Branch of Institute of Astronomy), V.
Petkov,  A. Kurenya (BNO INR RAS), A. Pozanenko (IKI) on behalf of larger
GRB follow up collaboration  report:

We observed the afterglow of GRB 080330 (Mao et al., GCN 7537) with the
Zeiss-2m telescope of  Mt.Terskol observatory on March 30.  The optical
counterpart (Klotz et al., GCN 7536; Mao et al., GCN 7537, Schaefer & Guver,
GCN 7538; Gomboc et al., GCN 7539; Bloom & Starr, GCN 7542) is clearly
detected.

The photometry of the afterglow against of the SDSS calibration stars (Cool
et al., GCN 7540) of the two epochs of combined images in R is following

T0+         exposure    R_mag
Mid time

0.575 d   4x900 s     21.05 +/-0.1
0.654 d   4x900 s     21.28 +/-0.1

Taking into account previous observation (R=20.4+/-0.2 at 9.4 hours after
burst, Wang et al., GCN 7550)  and  our observations one can suggest the
steepening of a power law decay index up to ~ 1.5 between 9.4 and 15.7 hours
after burst.


GRB_name: GRB080328A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7557
SUBJECT: GRB080328, RIMOTS optical upper limit
DATE:    08/04/01 09:54:59 GMT
FROM:    Hiroki Tanaka at U of Miyazaki  <hiro0218@astro.miyazaki-u.ac.jp>

H.Tanaka, K.Kono, R.Hara, N.Ohmori, H.hayasi, M.Yamauchi, E.Sonoda
(University of Miyazaki)

We have observed the field covering the error circle of
GRB080328 (GCN 7527, A.P. Beardmore et al.) with
the unfiltered CCD camera on the 30-cm telescope at
University of Miyazaki.
The observation was started 11:09:32 UT; about 186 minutes
after the Swift trigger time.

We have compared our data of 30 sec exposures
with the USNO-A2.0 catalog, there is no new source
at the reported position.

the upper limits are as follows:
--------------------------------------------------------------
Start(UT) End(UT) Num. of frames  Limit (mag.)
--------------------------------------------------------------
11:10:49 11:11:07  1   ~15.74
11:10:59 12:58:24  65   ~17.70
---------------------------------------------------------------


GRB_name: GRB080319B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7558
SUBJECT: GRB 080319B: TORTORA light curve (Correction)
DATE:    08/04/01 11:21:31 GMT
FROM:    Sergey Karpov at SAO RAS  <karpov@sao.ru>

S. Karpov, G. Beskin (SAO RAS, Russia), S. Bondar (RIPI, Russia), C. Bartolini,
G. Greco, A. Guarnieri, A. Piccioni (Astronomy Department of Bologna
University, Italy), D. Nanni, F. Terra (Second University of Roma "Tor
Vergata", Italy), E. Molinari, G. Chincarini, F.M. Zerbi, S. Covino, V. Testa
(Osservatorio Astronomico di Brera, Italy), G. Tosti (Universita di Perugia,
Italy), F. Vitali, L.A. Antonelli (Osservatorio Astronomico di Roma, Italy),
P. Conconi, G.  Cutispoto (Osservatorio Astronomico di Catania, Italy),
G. Malaspina (Osservatorio Astronomico di Brera, Italy), L. Nicastro (Istituto
di Astrofisica Spaziale e Fisica Cosmica, Palermo, Italy), E. Palazzi (Istituto
di Astrofisica Spaziale e Fisica Cosmica, Bologna, Italy), E. Meurs (Dunsink
Observatory, Ireland), P.  Goldoni (APC, SAp/CEA, Paris)

report on behalf of TORTOREM team:

We performed additional analysis of Tortora data on early optical
transient of GRB 080319B (GCN 7427, Racusin et al.)  reported by us in
GCN 7502 and found the systematic error of 6.1 s in the time zero
point. To compensate it, all data points have to be shifted 6.1 s to
earlier times. The modified light curve, also including minor
photometric adjustments, is available at

http://vo.astronet.ru/~karpov/grb080319b_lc_10_shifted.gif

We apologize for any inconvenience this may have caused.


GRB_name: GRB080330A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7559
SUBJECT: GRB080330: optical observations
DATE:    08/04/01 11:28:09 GMT
FROM:    Vladimir Sokolov at SAO RAS  <sokolov@sao.ru>

A. S. Moskvitin, T. A. Fatkhullin, V. N. Komarova, A. N. Burenkov (SAO-RAS,
Nizhnij Arkhyz)
on behalf of larger GRB follow up collaboration  report:


We observed the GRB 080330 afterglow (Mao et al., GCN 7537) in the R-band
(exposure 3x600 sec)
with the 1-m telescope of SAO RAS on March 30.928, 18.58 hours after the
trigger.
The weather conditions were tolerable.

The optical transient (Klotz et al., GCN 7536; Mao et al., GCN 7537,
Schaefer & Guver, GCN 7538; Gomboc et al., GCN 7539; Bloom & Starr,
GCN 7542; A. Sergeev et al., GCN 7556) is clearly detected.

The photometry of the afterglow is calibrated against 8 stars from USNO-A2.0.
The R-magnitude of the object is 21.49+/-0.28.

   This message may be cited.


GRB_name: GRB080330A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7560
SUBJECT: GRB 080330: Prompt PROMPT Observations
DATE:    08/04/02 14:47:56 GMT
FROM:    Mark Schubel at UNC/PROMPT  <mschubel@physics.unc.edu>

M. Schubel, D. Reichart, M. Nysewander, A. LaCluyze, K. Ivarsen, J. A. 
Crain, A. Foster, T. Brennan, J. Haislip, J. Styblova, and A. Trotter 
report:

Skynet observed the localization of GRB 080330 (Mao et al., GCN 7537) with 
two of the 16" PROMPT telescopes at CTIO beginning 31 seconds after the 
trigger (15 seconds after notification) in VRI.

We detect the afterglow (Klotz et al., GCN 7536) in all filters.  At 200 
seconds after the burst we measure R ~ 17.3 mag (calibrated to 11 USNO B1 
stars), at 246 seconds we measure I ~ 16.8 mag (calibrated to 11 USNO B1 
stars), and at 292 seconds we measure V ~ 16.6 mag (calibrated to 8 NOMAD 
stars).


GRB_name: GRB080330A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7561
SUBJECT: GRB080330: Improved Swift XRT Position
DATE:    08/04/03 09:58:40 GMT
FROM:    Jirong Mao at INAF-OAB  <jirong.mao@brera.inaf.it>

GRB080330: Improved Swift XRT Position

J. Mao (INAF-OAB) report on behalf of the Swift-XRT team:

Since the spacecraft began slowly drifting because the star tracker did 
not lock properly on the star field, the XRT position for GRB 080330 
that was distributed in GCN Circ. 7537 (Mao et al.) was incorrect. The 
initial on-borad XRT position determined immediately after the 
spacecraft slew was given by D. N. Burrows (GCN Circ. 7541). The final 
accurate XRT position from download data of Malindi is:

RA=169.2584d {11h 17m 02.02s} (J2000)

Dec=30.6229d{+30d 37' 22.58"} (J2000)
 
with the error radius 3.62 arcsec.


GRB_name: GRB080328A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7562
SUBJECT: GRB 080328: GAO 150cm telescope Optical Observation
DATE:    08/04/04 09:34:58 GMT
FROM:    Kenzo Kinugasa at Gunma Astro. Obs/Japan  <kinugasa@astron.pref.gunma.jp>

K. Kinugasa, O. Hashimoto, S. Honda, E. Nishihara, Y. Kozai (Gunma
Astronomical Observatory) and H. Karoji (NAOJ) report:

 The field of GRB 080328 (Perri et al. GCN 7525) was observed
with the 150 cm telescope of the Gunma Astronomical Observatory.
Starting at 09:49 UT (1.75 hours after the trigger), Rc frames
were acquired for 9 x 3-min exposures  under a poor seeing
(~4.5arcsec) condition.

 The UVOT position is close to a star, so that the field are affected
with the light from this star. We do not identify the optical counterpart
reported by UVOT to limiting magnitudes of Rc=20.7 relative to USNO-B1.0 R2
magnitudes at the meantime of 10:08 UT.

 Combining the results reported by Guidorzi et al. (GCN 7526), the decay
index is > 0.9, which is consistent with the intial index reported by
Guidorzi et al. (GCN 7526).


GRB_name: GRB080325A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7563
SUBJECT: GRB 080325: optical upper limit 
DATE:    08/04/04 15:16:08 GMT
FROM:    Graziella Pizzichini at IASF/CNR,Bologna  <pizzichini@iasfbo.inaf.it>

  F. Munz (INAF/IASF Bologna) F. Terra (Second University of
  Rome "Tor Vergata"), G. Greco, C. Bartolini, A. Guarnieri, A. Piccioni
  (Bologna University), G. Pizzichini (INAF/IASF Bologna),
  D. Nanni (INAF/OAR and Second University of Rome "Tor Vergata"),
  M. Redfern (National University of Ireland, Galway), A. De Blasi
  (Bologna Observatory) report:

  We observed the field of GRB 080325 (GCN 7512, Vetere et al.)
  with the 152 cm telescope located in Loiano.

  We obtained one 10 min exposure in the Rc filter at mean time
  2008 March 26 0.55  UT. Further observations were prevented by
  clouds and the moon. We do not detect any object in the Swift-XRT
  error box reported by Osborne et al. (GCN 7513).

  Our 3-sigma limiting magnitude is R~20.6 (based on Nomad1 catalogue).

  The image shall be posted in our public directory
  from where it can be retrieved by sftp using
  hostname: ermione.bo.astro.it
  username: publicGRB
  password: GRB_bo
  directory: GRB080325


GRB_name: GRB080405A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7564
SUBJECT: GRB 080405: Mars Oddysey and Swift-BAT detection, possible host galaxy
DATE:    08/04/06 04:59:33 GMT
FROM:    Jay R. Cummings at NASA/GSFC/Swift  <jayc@milkyway.gsfc.nasa.gov>

J. R. Cummings (NASA/GSFC/UMBC) on behalf of the Swift-BAT team
K. Hurley on behalf of the Mars Odyssey GRS team

At 09:18:55.6 UTC on April 5, 2008, BAT triggered on GRB 080405
(trigger #308549).  Automated attempts onboard to find a significant 
source in an image were prematurely terminated by a Swift preplanned 
slew manuver.

Mars Oddyssey GRS detected a ~10 s long event at 33236 s Mars time
(09:13:56 +/- 700 s Earth time), and the team informed the IPN.  The 
BAT team searched the BAT data for a corresponding event and found 
the failed onboard trigger and a large peak in the count rates.

Ground analysis of BAT data found a strong source at
RA, Dec 162.597,  -4.250, which is:

10h 50m 23.3s, -4d 15' 00" (J2000),

2.0 arcmin error radius (estimated 90% confidence). This is 0.4 arcmin
from [BTW2002] J105021.50-041505.9, the host galaxy of 2002AL (see
Becker et al. IAUC #7804).

The BAT light curve shows a slow-rise and slow-decay Gaussian-like
envelope with multiple peaks.  T90 is approximately 40 +- 5 seconds.
The peak countrate was about 9000 counts/sec at T+25 sec (15-350 keV). 
The source was 37% coded in the BAT field of view.  Because the burst 
was not detected onboard, the full burst response was not collected. 
Partial BAT data products will be available.

Swift will execute a TOO on April 6 for the narrow-field
instruments to observe this burst. 


GRB_name: GRB080405A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7565
SUBJECT: GRB 080405: Swift-XRT position
DATE:    08/04/07 10:04:46 GMT
FROM:    Boris Sbarufatti at INAF-IASF-Pa  <sbarufatti@ifc.inaf.it>

V. La Parola, B. Sbarufatti, V. Mangano (INAF-IASF PA) and D.N. Burrows
(PSU) report on behalf of the Swift XRT team.

The XRT began observing GRB 080405 (Cummings et al., GCN 7564) on
2008-04-07 at 04:25:49, ~43 hours after the trigger. The observation
is in PC mode and consists of 1.5 ksec split over two orbits. A
single uncatalogued source is detected in the whole XRT field of view,
with coordinates:
RA  = 10:50:23.64  (162.59850)
Dec = -04:17:18.5  (-4.288476)
with an uncertainty of 7.1 arcsec (radius, 90% containment). This
position lies 2.3 arcmin from the BAT position (slightly outside the
BAT error circle).
The source has a count rate of 1.029E-02  2.9E-03 c/s, corresponding to
an unabsorbed flux of 4.63e-13 ergs/s/cm-2  (assuming a standard
powerlaw spectrum with index 2.0 and a Galactic line of sight absorbing
column of 3.8e20 cm-2).
With these data we cannot assess if the source is decaying.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB080405A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7566
SUBJECT: GRB 080405: Swift-BAT refined analysis
DATE:    08/04/07 14:25:11 GMT
FROM:    Jay R. Cummings at NASA/GSFC/Swift  <jayc@milkyway.gsfc.nasa.gov>

T. Sakamoto  (GSFC/ORAU), L. Barbier (GSFC), S. Barthelmy (GSFC), 
J. Cummings (GSFC/UMBC), M. Stamatikos (GSFC/ORAU), T. Ukwatta (GWU),
K. McLean (GSFC/UMD), W. Baumgartner (GSFC/UMBC), E. Fenimore (LANL), 
H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), D. Palmer (LANL),
G. Sato (GSFC/ISAS), J. Tueller (GSFC)
(i. e. the Swift-BAT team)

We report further results on GRB 080405 (Cummings et al. GCN circ
#7564) based on the BAT event data from T-1.3 to T+8.7 seconds.
This interval covers only about the first fifth of the event, and
not the interval of peak flux.

The best BAT position remains the same: RA, Dec 162.597,  -4.250 deg
which is:
RA(J2000)  = 10h 50m 23.3s,
Dec(J2000) = -4d 15' 00" (J2000)
with an uncertainty of 2.0 arcmin (radius, sys+stat, 90% containment).

The burst was 36% coded at T0.  A Swift preplanned slew began at
about T+4 sec, and the burst left BAT's coded field of view entirely
at about T+45 sec.  The unweighted counting rates are still somewhat
sensitive to photons entering through the side of the instrument.

These rates show a slow rise becoming detectable beginning about
T-4 seconds, rising to a series of overlapping peaks at T+12, T+20, 
T+27, T+32, T+36, T+44, and T+47 seconds, with the peak at T+27 
appearing the highest.  The burst seems to follow an approximately 
Gaussian envelope (though as noted, the profile is modulated by the 
slew and by scattering and transmission through the side of the 
instrument).  T90 is 40 +-5 seconds. It fades below detectability at 
about T+52 seconds.

The spectrum from T-1.3 to T+8.7 sec is well fit by a single
power-law function with a photon index of 1.28 +- 0.07.  The fluence
is (1.2 +- 0.1) x 10^-6 ergs/cm2.  We estimate that the total fluence
of the entire burst is ~5 x 10-5 ergs/cm2; i. e. we caught only a
small fraction of the burst in our detailed data.


GRB_name: GRB080319B
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7567
SUBJECT: GRB 080319B: Potential Jet Break Observed by Swift-XRT and UVOT
DATE:    08/04/07 19:44:51 GMT
FROM:    Judith Racusin at PSU  <racusin@astro.psu.edu>

J.L. Racusin (PSU), S.R. Oates (UCL-MSSL), P. Schady (UCL-MSSL), S. T.
Holland (CRESST/USRA/GSFC), D.N. Burrows (PSU), report on behalf of the
Swift XRT and UVOT teams:

We have analyzed the first 19 days of Swift XRT data from GRB 080319B
(Racusin et al. GCN 7427), with a total exposure time of 200 ks.  The
light curve can be fit by a triple broken power-law with initial decay
slope of 1.54+/-0.01, breaking at 2790+/-664 s to a slope of 1.85+/-0.05,
breaking again at 41.4+/-9.0 ks to a slope of 1.17+/-0.06, and finally
breaking at 1.04+/-0.43 Ms to a slope of 2.9+/-2.3.

If this last break is interpreted as a jet break, the jet opening
half-angle is 8 degrees x (n/10 cm^-3)^(1/8).  We obtained Eiso=1.3x10^54
ergs (25 kev - 7 MeV) from Golenetskii et al. (GCN 7482), assuming
cosmological parameters of H_0=70 km/s/Mpc, Omega_M=0.3, Omega_Lambda =
0.7.  The corresponding beaming corrected energy is 1.3 x 10^52 ergs.

The uncertanties in the post-jet break slope and time are large.
Therefore, the evidence for a break is preliminary and further
observations will be required to confirm it.

Late-time UVOT white filter observations are also suggestive of a break at
approximately the same time as the X-ray break.  However, further
observations are needed to confirm the break because the afterglow flux is
near the UVOT detection limit.

We strongly encourage additional late-time optical follow-up to further
test for achromaticity and constrain the possible jet break.

This circular is an official product of the Swift Team.


GRB_name: GRB080330A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7568
SUBJECT: GRB 080330: RAPTOR detection of prompt optical flash
DATE:    08/04/07 20:55:40 GMT
FROM:    James Wren at LANL  <jwren@nis.lanl.gov>

J. Wren, W.T. Vestrand, P.R. Wozniak, H. Davis
of Los Alamos National Laboratory report:

Our RAPTOR telescopes responded to Swift trigger 308041
(Mao et al., GCN 7537) at 03:41:39.93 UTC, 23.1 seconds
after the trigger.  Our observations show an optical flash
(about 10 s duration) at T ~ 60 s that is simultaneous
with the fourth gamma-ray peak detected by that BAT
(Markwardt et al., GCN 7549).  Subsequently, we detect the
rise of an optical afterglow starting at T ~ 150 s that
levels off to a flat plateau at around T ~ 300 s and then
starts to rapidly decay after about T ~ 2000 s.  The
unfiltered measurements reported in the following table
are calibrated to the USNO-B1 R band.

t-mid(s)    exp(s)     mag     mag-err
-----------------------------------------
38.78       31.4      (18.3)   5 sigma limit
58.88       5.0       17.46    0.22
83.15       31.3      (18.4)   5 sigma limit
141.96      22.7      17.62    0.10
294.80      22.7      17.03    0.07
504.74      15.0      17.15    0.06


GRB_name: GRB080319B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7569
SUBJECT: GRB 080319B: HST observations
DATE:    08/04/08 00:55:27 GMT
FROM:    Nial Tanvir at IofA U.Cambridge  <nrt@ast.cam.ac.uk>

N. R. Tanvir (U. Leicester), A. J. Levan (U. Warwick),
A. S. Fruchter, J. Graham (STScI), K. Wiersema, E. Rol (U. Leicester)
report on behalf of a larger collaboration:

We obtained observations of GRB 080319B (GCN 7427) with HST/WFPC2 in
F606W and F814W filters on 2008 April 7th (2 orbits in each filter).

These data show the fading afterglow at magnitude F(814W_AB)=24.2
and F(606W_AB)=24.5.  This fading is consistent within
the errors with a continued power-law decline in optical
brightness.

PSF subtraction reveals no obvious sign of an underlying host galaxy,
although there is what appears to be a separate galaxy 1.5 arcsec to
the south, which might be producing one of the foreground absorption
systems (GCN 7451).

A colour image showing the field around the GRB is available at:

 http://www.star.le.ac.uk/~nrt3/080319b.html

Further analysis is ongoing.


GRB_name: GRB080319A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7570
SUBJECT: GRB 080319A: Early RAPTOR optical limits
DATE:    08/04/08 20:42:18 GMT
FROM:    James Wren at LANL  <jwren@nis.lanl.gov>

J. Wren, W.T. Vestrand, P.R. Wozniak, H. Davis
of Los Alamos National Laboratory report:

Our RAPTOR telescopes imaged the location of Swift trigger
306754 (Pagani et al., GCN 7426).  We do not detect the optical
counterpart initially reported by Cenko et al. (GCN 7429).  The
location of the counterpart was within the field of view of our
continuous all-sky monitoring system.  We can place 5 sigma
limits at approximately magnitude 9.0 during the time period
within 5 minutes both before and after the trigger.  Our
narrow-field instruments began observing the location at
05:46:51.90 UTC, 69.8 s after the Swift trigger, but also did
not detect the counterpart.  The limiting magnitudes of our
unfiltered observations when calibrated to the USNO-B1 R-band
are given in the following table.

t-mid(s)    exp(s)     mag     mag-err
--------------------------------------------
-19.18      10.0       9.0     5 sigma limit
14.07       10.0       9.0     5 sigma limit
72.35        5.0      16.9     5 sigma limit
156.60      10.0      17.4     5 sigma limit
423.25      30.0      18.0     5 sigma limit


GRB_name: GRB080408A
Detection_method: superAGILE
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7571
SUBJECT: GRB 080408: GRB Localization by SuperAGILE
DATE:    08/04/08 20:56:13 GMT
FROM:    Marco Feroci at IASF/INAF  <feroci@iasf-roma.inaf.it>

Subject: GRB 080408: Gamma Ray Burst Localization by SuperAGILE

P. Soffitta, I. Donnarumma, E. Del Monte, M. Feroci, Y. Evangelista, 
E. Costa, I. Lapshov, F. Lazzarotto, L. Pacciani, M. Rapisarda
(INAF/IASF Rome), A. Giuliani, S. Vercellone, A. Chen, S. Mereghetti, A. 
Pellizzoni, F. Perotti, F. Fornari, M. Fiorini, P. Caraveo, 
A. Zambra (INAF/IASF Milan), A. Bulgarelli, F. Gianotti, 
M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, 
M. Galli, (INAF/IASF Bologna), M. Tavani, G. Pucella, F. D'Ammando, V. 
Vittorini, A. Argan, A. Trois (INAF/IASF Rome), G. Barbiellini, 
F. Longo (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2),  
M. Prest, E. Vallazza (Universita' dell'Insubria), P. Lipari, 
D. Zanello (INFN Roma-1), and  P. Giommi, C. Pittori,  
(ASDC) and L. Salotti (ASI), on bhealf of the AGILE Team, report:

"SuperAGILE detected and localized a gamma ray burst 
on April 8th, at 18:12:48 UT. The event was approximately 
13 degrees off-axis. The observed duration in the 20-60 keV
energy range is about 20 seconds, with a single pulse structure.
The burst was triggered and localized onboard, although distributed
after verfication on ground.  
The burst position was reconstructed as (RA, Dec) (114.678 deg, 
33.305 deg), which is:

RA(J2000) = 07h 38m 42.68s
Dec(J2000) = 33d 18' 16.7"

with an uncertainty of 3' radius. The given uncertainty accounts 
for both the statistical and systematic errors. 

An analysis of the AGILE Gamma Ray Imager (GRID) data is in progress."

This message may be cited.


GRB_name: GRB080408A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7572
SUBJECT: GRB 080408: Analysis of AGILE Gamma-ray data
DATE:    08/04/08 21:56:59 GMT
FROM:    Sandro Mereghetti at IASF/CNR  <sandro@iasf-milano.inaf.it>

S. Mereghetti, S. Vercellone, A. Giuliani, A. Chen, A. Pellizzoni, F. 
Perotti, F. Fornari, M. Fiorini, P. Caraveo, A. Zambra (INAF/IASF Milan), 
P. Soffitta, I. Donnarumma, E. Del Monte, M. Feroci, Y. Evangelista, E. 
Costa, I. Lapshov, F. Lazzarotto, L. Pacciani, M. Rapisarda (INAF/IASF 
Rome), A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, 
F. Fuschino, M. Marisaldi, M. Galli, (INAF/IASF Bologna), M. Tavani, G. 
Pucella, F. D'Ammando, V. Vittorini, A. Argan, A. Trois (INAF/IASF Rome), 
G. Barbiellini, F. Longo (INFN Trieste), P. Picozza, A. Morselli (INFN 
Roma-2), M. Prest, E. Vallazza (Universita' dell'Insubria), P. Lipari, D. 
Zanello (INFN Roma-1), and P. Giommi, C. Pittori, (ASDC) and L. Salotti 
(ASI), on behalf of the AGILE Team, report:


A preliminary analysis of the AGILE GRID data (E>100 MeV) does not show 
any significant gamma ray emission at the time and coordinates of the 
burst GRB 080408 localized by SuperAGILE (GCN 7571).

This message may be cited.


GRB_name: GRB080409A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7573
SUBJECT: GRB 080409: Swift detection of a burst
DATE:    08/04/09 01:46:36 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

S. T. Holland (CRESST/USRA/GSFC), W. H. Baumgartner (GSFC/UMBC),
D. N. Burrows (PSU), J. R. Cummings (NASA/UMBC), J. A. Kennea (PSU),
C. B. Markwardt (CRESST/GSFC/UMD), F. E. Marshall (NASA/GSFC),
K. M. McLean (GSFC/UMD), K. L. Page (U Leicester),
D. M. Palmer (LANL), R. L. C. Starling (U Leicester) and
T. N. Ukwatta (GSFC/GWU) report on behalf of the Swift Team:

At 01:22:57 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 080409 (trigger=308812).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 84.333, +5.085 which is 
   RA(J2000) = 05h 37m 20s
   Dec(J2000) = +05d 05' 07"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a double-peaked
structure with a duration of about 10 sec.  The peak count rate
was ~5000 counts/sec (15-350 keV), at ~0.7 sec after the trigger. 

The XRT began observing the field at 01:24:21.6 UT, 84.0 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued
X-ray source with an enhanced position: RA, Dec 84.33035, 5.08523 which
is equivalent to:
  RA(J2000)  = 05h 37m 19.28s
  Dec(J2000) = +05d 05' 06.8"
with an uncertainty of 2.9 arcseconds (radius, 90% containment). This
location is 9.5 arcseconds from the BAT onboard position, within the
BAT error circle. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density in excess of the Galactic value (2.34e+21
cm^-2, Kalberla et al. 2005), with an excess column of 4.5
(+4.33/-3.19) x 10^21 cm^-2 (90% confidence). The relation of Grupe et
al. (2007) implies that this burst has a redshift z<4.3, although high
redshift fits to the absorbed XRT spectrum are possible if paired with
an anomalously large column. A summary of the promptly downlinked data
is given at http://www.swift.ac.uk/sper/308812/. 

UVOT took a finding chart exposure of  95 seconds with the White (160-650 nm)
filter starting 87 seconds after the BAT trigger. No afterglow candidate has
been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of
the XRT error circle. The 3-sigma upper limit is about 19.5 mag. 
No correction has been made for the expected extinction corresponding to E(B-V)
of 0.78 mag. 

Burst Advocate for this burst is S. T. Holland (sholland AT milkyway.gsfc.nasa.gov). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB080409A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7574
SUBJECT: GRB 080409: REM optical/NIR observations
DATE:    08/04/09 02:28:26 GMT
FROM:    Paolo D'Avanzo at INAF-OAB  <paolo.davanzo@brera.inaf.it>

P. D'Avanzo, S. Covino, D. Malesani, D. Fugazza, L.A. Antonelli, L. 
Calzoletti, S. Campana, G. Chincarini, M.L. Conciatore, S. Cutini, V. 
D'Elia, F. D'Alessio, F. Fiore, P. Goldoni, D. Guetta, C. Guidorzi, G.L. 
Israel, E. Maiorano, N. Masetti, A. Melandri, E.J.A. Meurs, L. Nicastro, 
E. Palazzi, E. Pian, F. Piranomonte, S. Piranomonte, L. Stella, G. 
Stratta, G. Tagliaferri, G. Tosti, V. Testa, S.D. Vergani, and F. 
Vitali, report on behalf of the REM team:

The robotic 60-cm REM telescope located at La Silla (Chile) observed 
automatically the field of the GRB 080409 (Holland et al., GCN 7573) 
starting about 81 seconds after the burst. Airmass was large (about 2.9).

Preliminary photometry of our earliest images (R: 30 s, H: 50 s) reveal 
no new sources inside the XRT error circle down to 3sigma limiting 
magnitudes of H ~ 15.0 and R ~ 17.0.

[GCN OPS NOTE(09apr08): Per author's request, the "080309" in the Subject-line
and in the body of the Circular was changed to "080409".]


GRB_name: GRB080409A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7575
SUBJECT: GRB 080409: Enhanced Swift-XRT position
DATE:    08/04/09 04:12:30 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 91 s of overlapping XRT Photon Counting mode and UVOT
data for GRB 080409, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 84.32975, +5.08484 which is equivalent
to:

RA (J2000): 05h 37m 19.14s
Dec (J2000): +05d 05' 05.4"

with an uncertainty of 2.0 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest position
can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is
described by Goad et al. (2007, A&A, 476, 1401
http://www.swift.ac.uk/xrt_positions/Goad.pdf), the current algorithm is an
extension of this method.

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB080408A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7576
SUBJECT: GRB 080408: Swift-XRT position of a possible afterglow
DATE:    08/04/09 08:04:22 GMT
FROM:    Kim Page at U.of Leicester  <kpa@star.le.ac.uk>

K.L. Page (U. Leicester) reports on behalf of the Swift-XRT Team:

Swift performed a Target of Opportunity observation of the SuperAGILE GRB 
080408 (Soffitta et al., GCN Circ 7571), starting ~25 ks after the 
trigger. The intended observation was cut short by the BAT detection of 
GRB 080409 (Holland et al., GCN Circ. 7573), but a source is still 
detected during the 800 s of data obtained, at a position of RA, Dec = 
114.66547, +33.30341, which is equivalent to

RA(J2000):   07 38 39.71
Dec(J2000): +33 18 12.3

with an uncertainty of 8.6 arcsec (radius, 90% containment). This is 38.1 
arcsec from the SuperAGILE position, within their error circle.

The source has a count rate of 0.010 +/- 0.004 count s^-1, however, with 
the limited data, it is not possible to determine whether it is fading.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB080408A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7577
SUBJECT: UVOT/Swift Observations of GRB080408
DATE:    08/04/09 11:20:42 GMT
FROM:    Patricia Schady at MSSL/Swift  <ps@mssl.ucl.ac.uk>

P. Schady (MSSL-UCL) reports on behalf of the Swift-UVOT team:

The Swift/UVOT performed a Target of Opportunity observation on the SuperAGILE 
GRB 080408 (Soffitta et al., GNCN Circ. 7571), starting ~7hrs after the 
trigger. Observations were made in the b, u and uvw1 filters. The optical 
afterglow is not detected in any of these filters at the XRT position (Page et 
al., GCN Circ 7576) down to the following 3 sigma upper limits:

Filter  Tstart  Exp   Mag UL (3sig)
         (hrs)   (s)
b       7.12    185   > 19.96
u       7.06    200   > 19.63
uvw1    6.95    399   > 19.97

The above magnitudes are not corrected for the Galactic extinction 
corresponding to a reddening of E(B-V)=0.04 mag (Schlegel et al., 1998, ApJS, 
500, 525). The photometry is on the UVOT flight system described in Poole et 
al. (2008, MNRAS, 383, 627).


GRB_name: GRB080409A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7578
SUBJECT: GRB 080409: Swift XRT refined analysis
DATE:    08/04/09 11:53:54 GMT
FROM:    Rhaana Starling at U of Leicester  <rlcs1@star.le.ac.uk>

R.L.C. Starling, P.A. Evans, K.L. Page (U. Leicester) and S.T. Holland 
(CRESST/USRA/GSFC) report, on behalf of the Swift XRT team:

We have analysed the first three orbits of Swift XRT data (5.8 ks of data 
from T0+96s to T0+1.29e4s) for GRB 080409 (Holland et al., GCN Circ. 
7573). The enhanced position for the X-ray afterglow is given in Evans et 
al. (GCN Circ. 7575).

The light curve shows an initial increase with slope of alpha1~0.6 up to
T~480s. The light curve then turns over to decay with a slope of
alpha2=-0.8+/-0.1.  

The Photon Counting mode spectrum collected from the first three orbits 
can be fit with an absorbed power law of photon index Gamma=2.2+0.5/-0.7 
and a total absorbing column of NH=(5 +5/-4)e21 cm-2, exceeding the 
Galactic value of 2.4e21 cm-2. The 0.3-10 keV observed (unabsorbed) flux 
is 3.2e-12 (6.7e-12) erg/cm2/s, corresponding to a count rate of 5.8e-2 
count/s and a count rate to flux conversion of 1 count/s = 5.6e-11 erg/cm2/s.

The predicted count rates at T0+24h and T0+48h are 6.8e-3 and 4.0e-3 
count/s respectively, assuming the decay continues with alpha=-0.8.

This is an official product of the Swift XRT team.


GRB_name: GRB080409A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7579
SUBJECT: Swift/UVOT observations of GRB080409
DATE:    08/04/09 13:01:18 GMT
FROM:    Patricia Schady at MSSL/Swift  <ps@mssl.ucl.ac.uk>

Swift/UVOT began settled observations of the field of GRB 080409 starting 
88s after the BAT trigger (Holland et al., GCN Circ 7573). We do not 
detect an optical/uv afterglow at the enhanced XRT position (Evans et al., 
GCN Circ. 7575) in the initial finding chart observations or subsequent 
summed images down to the following 3 sigma upper limits:

Filter  T_start T_stop  Exp.    Mag UL (3sig)
  (s) (s) (s)
white   88      187     93      > 20.22
white   682     7079    494     > 21.16
v       188     587     393     > 19.45
v       721     12243   1099    > 20.03
b       667     676     412     > 20.42
u       642     661     432     > 20.13
uvw1    618     637     430     > 19.86
uvm2    593     12940   1070    > 20.23
uvw2    697     11330   1082    > 20.46

The above magnitudes are not corrected for the large Galactic extinction 
in the line of sight to GRB 080409, corresponding to a reddening of 
E(B-V)=0.78 mag (Schlegel et al., 1998, ApJS, 500, 525). The photometry is 
on the UVOT flight system described in Poole et al. (2008, MNRAS, 383, 
627).


GRB_name: GRB080330A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7580
SUBJECT: GRB 080330 optical observations
DATE:    08/04/09 18:36:58 GMT
FROM:    AAVSO GRB Network at AAVSO  <matthewt@aavso.org>

A. Block (Seeing In The Dark Internet Telescope, and Steward
Observatory, Tucson, AZ) and M. Templeton (AAVSO) report on behalf of
the AAVSO International High Energy Network the following observations
and analysis of the optical afterglow of GRB 080330 (Mao et al., GCN
Circular #7537; Klotz, Boer, and Atteia, GCN #7536):

Adam Block reports unfiltered photometry of the GRB 080330 afterglow
spanning 2008 March 30.1675 UT to 2008 March 30.3273, taken with the
Seeing In The Dark Internet Telescope 14-inch Celestron SCT, using an
SBIG ST1001 camera, located near Mayhill, New Mexico.  Forty-seven,
300-second unfiltered exposures were obtained beginning 20 minutes
post-burst, and continuing through t0 + 0.1736 days. Data acquisition
began after the reported peak (D'Avanzo, et al., GCN #7554), but during
the early decay epoch.  A break in the light curve is apparent at
approximately 25 minutes after the trigger; only one data point was
obtained prior to this point, and so a slope cannot be reliably derived. 
After t0 + 25 minutes, the data are reasonably well fit with a power law
index of -1.104 +/- 0.001, with a zero point unfiltered magnitude of
22.65 (m = m(t+1day)).  However, the light curve appeared to briefly
rebrighten by more than 0.2 magnitudes (1-sigma error = 0.09 mag)
approximately 70 minutes post-burst, suggesting a late-time
manifestation of the rebrightening seen during early light (Schaefer and
Guver, GCN #7538).  These observations are consistent with other
optical observations taken during this time frame; observations through
t0 + 250 minutes do not show evidence for the steeper slope described by
Sergeev et al (GCN #7556) for data taken at t > t0 + 0.5 days,
suggesting this break occurred between the end of these observations and
the start of observations by Sergeev et al.

A report detailing these observations is available at the following URL:

ftp://ftp.aavso.org/grb/AdamBlock_GRB080330_2454558.33910_.txt

The initial image of the GRB field is available at the following URL:

ftp://ftp.aavso.org/grb/AdamBlock_GRB080330_2454558.33910_.fits

A light curve of the unfiltered photometry is available at the following
URL:

http://www.caelumobservatory.com/outgoing/grb080330LOG.jpg

Photometry and a full description of the observations will appear in the
Journal of the AAVSO, and are available from A. Block upon request to
ngc1535@caelumobservatory.com.

The AAVSO thanks the Curry Foundation for their continued support of the
AAVSO International High Energy Network.


GRB_name: GRB080408A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7581
SUBJECT: GRB 080408: GROND detection of optical/NIR afterglow candidate
DATE:    08/04/10 06:55:11 GMT
FROM:    Thomas Kruehler at MPE/MPI  <kruehler@mpe.mpg.de>

T. Kruehler, J. Greiner, A. Kupcu Yoldas, C. Clemens, A. Yoldas (all MPE
Garching) and G. Szokoly (Eoetvoes Univ., Budapest and MPE Garching)
report on behalf of the GROND team:

We observed the field of GRB 080408 detected by SuperAGILE (Soffitta et
al., GCN #7571) simultaneously in g'r'i'z'JHK with GROND mounted at the
2.2m ESO/MPI telescope at La Silla Observatory (Chile).

Observations started at 23:22:39 UT on April 8th, 2008, 5h 10min, and 
continued on April, 9th at 23:21:34 UT, 29h 9min after the burst. Due to
visibility constraints, only about 1 hr of observations were obtained at
each epoch.

In the first epoch we detect a single point source in the XRT error 
circle (Page et al. GCN #7576) at

RA (J2000) = 07:38:39.59
DEC (J2000) = +33:18:14.9

with an uncertainty of 0.5".

The object is detected in all of the seven bands, implying a redshift
smaller than 3.5.

Preliminary photometry yields magnitudes of g' = 23.12, r' = 22.03, i' =
21.62, z' = 21.26, J = 20.60, H = 19.90 and K = 19.06, with typical 
errors of +/- 0.10 in g'r'i'z' and +/- 0.15 in JHK. Magnitudes are
calibrated against USNO and 2MASS field stars.

In the second night, the object had faded to a r' band magnitude of 23.2
+/- 0.2.

We therefore suggest this to be the afterglow of GRB 080408.

The given magnitudes are not corrected for the Galactic foreground
reddening of E(B-V)=0.04 mag (Schlegel et al., 1998).


GRB_name: GRB080409A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7582
SUBJECT: GRB 080409: Swift-BAT refined analysis
DATE:    08/04/10 13:14:20 GMT
FROM:    Jay R. Cummings at NASA/GSFC/Swift  <jayc@milkyway.gsfc.nasa.gov>

D. Palmer (LANL), S. D. Barthelmy (GSFC), W. Baumgartner (GSFC/UMBC) ,
J. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC),
S. T. Holland (CRESST/USRA/GSFC), H. Krimm (GSFC/USRA),
C. Markwardt (GSFC/UMD),  K. McLean (GSFC/UMD), A. Parsons (GSFC),
T. Sakamoto (GSFC/UMBC), G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU),
J. Tueller (GSFC), T. Ukwatta (GWU)
(i.e. the Swift-BAT team):

Using the data set from T-239 to T+963 sec from the recent telemetry
downlink, we report further analysis of BAT GRB 080409 (trigger #308812)
(Holland, et al., GCN Circ. 7573).  The BAT ground-calculated position
is RA, Dec = 84.304, 5.078 deg which is
   RA(J2000)  =  05h 37m 12.9s
   Dec(J2000) = +05d 04' 39.9"
with an uncertainty of 2.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 46%.

The mask-weighted light curve shows 3 well-separated peaks, at T-13,
T+0, and T+10 sec, that are about 1, 2, and, 2 sec wide respectively.
The first is much smaller than the others, the second at T+0 is the
largest.  T90 (15-350 keV) is 20.2 +- 8.0 sec (estimated error including
systematics).

The time-averaged spectrum from T-13.1 to T+10.4 sec is best fit by a
simple power-law model.  The power law index of the time-averaged
spectrum is 2.10 +- 0.20.  The fluence in the 15-150 keV band is
6.1 +- 0.7 x 10^-07 erg/cm2.  The 1-sec peak photon flux measured from
T+0.00 sec in the 15-150 keV band is 3.7 +- 0.3 ph/cm2/sec.  All the
quoted errors are at the 90% confidence level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/308812/BA/


GRB_name: GRB080330A
Detection_method: retraction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7583
SUBJECT: GRB 080330: Swift-XRT refined position retraction
DATE:    08/04/11 14:32:16 GMT
FROM:    Jirong Mao at INAF-OAB  <jirong.mao@brera.inaf.it>

J. Mao and C. Guidorzi (INAF-OAB) on behalf of the Swift-XRT team report:

A re-examination of the XRT data on GRB080330 (Mao et al.
GCN Circ. 7537) taken during the first orbit revealed that
the XRT improved position distributed by Mao (GCN Circ. 7561)
is incorrect due to star tracker loss-of-lock problems already
mentioned by Burrows (GCN Circ. 7541).
We re-processed the first orbit PC data and extracted the following
refined position from 136 to 311 s after the burst,
when the star tracker drifting seems to have little impact:
RA, Dec = 169.26950, +30.62355 which is equivalent to:

RA (J2000): 11h 17m 04.68s
Dec (J2000): +30d 37' 24.78"

with an uncertainty of 4.0 arcsec (radius, 90% confidence).
This is consistent with the optical ground-based position
(2.7 arcsec away from the PAIRITEL position reported by
Bloom and Starr, GCN Circ. 7542).

This is an official product of the Swift XRT team.


GRB_name: GRB080411A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7584
SUBJECT: GRB 080411: Swift detection of a bright burst
DATE:    08/04/11 21:47:27 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

F. E. Marshall (NASA/GSFC), S. D. Barthelmy (GSFC),
W. H. Baumgartner (GSFC/UMBC), A. P. Beardmore (U Leicester),
D. N. Burrows (PSU), N. Gehrels (NASA/GSFC), O. Godet (U Leicester),
S. T. Holland (CRESST/USRA/GSFC), H. A. Krimm (CRESST/GSFC/USRA),
C. B. Markwardt (CRESST/GSFC/UMD), K. M. McLean (GSFC/UMD),
C. Pagani (PSU), K. L. Page (U Leicester), D. M. Palmer (LANL),
M. Stamatikos (NASA/ORAU), R. L. C. Starling (U Leicester),
T. N. Ukwatta (GSFC/GWU), L. Vetere (PSU) and P. A. Ward (MSSL-UCL)
report on behalf of the Swift Team:

At 21:15:32 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 080411 (trigger=309010).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 38.018, -71.342 which is 
   RA(J2000)  =  02h 32m 04s
   Dec(J2000) = -71d 20' 30"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The TDRSS BAT lightcurve shows the burst
starting with a fast rise from background to ~13,000 counts/sec in
approximately 0.5 sec.  There are several peaks after that with the
fourth peak (T+19 sec) at 75,000 cnts/sec.  There are several more peaks 
after that lasting out to at least T+70 sec. 

The XRT began observing the source at 21:16:42 UT (71 s after the 
trigger).  The XRT centroided on something very bright. 
We have lost most of our prompt diagnostic messages
because the spacecraft switched from TDRSS telemetry
to Malindi telemetry shortly after the burst, and our
prompt image does not include the source.  However,
the information within the header indicates that the
source is located near the center of the XRT field
of view, and is therefore probably real.  If real,
the position is 
GRB_RA:           37.9860d {+02h 31m 56.6s} (J2000),
GRB_DEC:         -71.3021d {-71d 18' 07.5"} (J2000),

with an uncertainty of 4.3 arcseconds (90% confidence 
radius), and the flux during this image was approximately
4.4e-7 cgs (~ 10 Crabs) in the 0.1 s image.  The XRT 
position is 148 arcseconds from the BAT position. 

No UVOT data for this burst are currently available. 

Burst Advocate for this burst is F. E. Marshall (marshall AT milkyway.gsfc.nasa.gov). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB080330A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7585
SUBJECT: GRB080330: MAGIC telescope GeV observation
DATE:    08/04/11 23:41:23 GMT
FROM:    Markus Garczarczyk at MPI/MAGIC  <garcz@mppmu.mpg.de>

Gaug M., Garczarczyk M., Antonelli A., Bastieri D., Covino S., Galante N., 
La Barbera A., Longo F. and Scapin V. for the MAGIC collaboration

The MAGIC Imaging Atmospheric Cherenkov Telescope performed a follow-up 
observation of the BAT burst GRB080330 (GCN circular 7537, Mao et al.).
We received the GCN alert at 03:41:33 UT (T0+16s), data taking with MAGIC 
started at 03:42:47 UT (T0+91s), short after the prompt emission phase 
measured to be T90=61+/-9s. The observation was carried out at a zenith 
angle of 48 degrees. The observation continued for 1039s.

No evidence for VHE gamma-ray emission above the analysis threshold of
313 GeV was found. The observation was carried out in (less sensitive) 
moon-observation mode.

A preliminary analysis, for the hypothesis of steady emission and 
assumption of a differential photon spectral index of -2.5, yields the 
following 95% CL differential flux upper limits, including a 30% 
systematic uncertainty on the telescope efficiency:

E (175- 300 GeV): 0.36 * 10^-10 erg/cm^-2/s
E (300-1000 GeV): 0.49 * 10^-10 erg/cm^-2/s
for a time window from 03:42:47 UT to 03:59:01 UT

We can also exclude emission of a constant flux in any 100s time bin 
smaller than:

E (175- 300 GeV): 8.42 * 10^-10 erg/cm^-2/s
E (300-1000 GeV): 2.05 * 10^-10 erg/cm^-2/s
for a time window from 03:42:47 UT to 03:59:01 UT

This message can be cited.


GRB_name: GRB080411A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7586
SUBJECT: GRB 080411: GROND detection of optical afterglow candidate
DATE:    08/04/11 23:51:51 GMT
FROM:    Thomas Kruehler at MPE/MPI  <kruehler@mpe.mpg.de>

T. Kruehler, A. Kupcu Yoldas, J.Greiner, C. Clemens, A. Yoldas (all MPE
Garching) and G. Szokoly (Eoetvoes Univ., Budapest and MPE Garching)
report on behalf of the GROND team:

We observed the field of GRB 080411 detected by BAT (Marshall et al., GCN
#7584) simultaneously in g'r'i'z'JHK with GROND mounted at the 2.2m
ESO/MPI telescope at La Silla Observatory (Chile).

Observations started in twilight at 23:15 UT on April 11th, 2008, 2h after
the burst.

We detect a new bright point source just at the edge of the XRT error
circle (Marshall et al. GCN #7584) at

RA (J2000) = 02:31:55.20
DEC (J2000) = -71:18:07.6

with an uncertainty of 0.8".

The object is detected in all of the seven bands, implying a redshift
smaller than 3.5.

Preliminary photometry yields an r' band magnitudes of 16.5 calibrated
against USNO field stars.

The given magnitudes are not corrected for the Galactic foreground
reddening of E(B-V)=0.03 mag (Schlegel et al., 1998).


GRB_name: GRB080411A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7587
SUBJECT: GRB 080411: VLT redshift
DATE:    08/04/12 01:51:01 GMT
FROM:    Daniele Malesani at Niels Bohr Inst,Dark Cosmology Center  <malesani@astro.ku.dk>

Christina C. Thoene (DARK/NBI), Annalisa De Cia (Univ. Iceland), Daniele 
Malesani, and Paul M. Vreeswijk (DARK/NBI), report:

We observed the optical afterglow of GRB 080411 (Marshall et al., GCN 
7584; Kruehler et al., GCN 7586) wih the ESO VLT equipped with FORS1 
with grism 300V. In a 600 s exposure taken at large airmass (average of 
2.45) the afterglow trace is clearly detected. The mean time of the 
observations is Apr 11.987 UT (2.4 hr after the trigger). In the 
acquisition image, we measure R = 17.25 based on archival zeropoints.

We detect very strong absorption lines from Mg II, Mg I, Fe II and 
several other ions at a redshift z = 1.03. Given the strength of the 
features, we consider this to be the redshift of the GRB. We caution 
that the wavelength calibration is based on archival data.

We acknowledge excellent support from the ESO staff, who carried out 
this difficult observation, in particular Swetlana Hubrig.


GRB_name: GRB080411A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7588
SUBJECT: GRB 080411: Enhanced Swift-XRT position
DATE:    08/04/12 02:31:39 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 1122 s of overlapping XRT Photon Counting mode and UVOT
data for GRB 080411, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 37.97852, -71.30188 which is equivalent
to:

RA (J2000): 02h 31m 54.84s
Dec (J2000): -71d 18' 06.8"

with an uncertainty of 1.5 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest position
can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is
described by Goad et al. (2007, A&A, 476, 1401
http://www.swift.ac.uk/xrt_positions/Goad.pdf), the current algorithm is an
extension of this method.

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB080411A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7589
SUBJECT: Konus-Wind observation of GRB 080411
DATE:    08/04/12 08:39:42 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val@mail.ioffe.ru>

S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks,
and T. Cline on behalf of the Konus-Wind team report:

The long GRB 080411 (Swift-BAT trigger #309010: Marshall et al., GCN
7584) triggered Konus-Wind at T0=76532.496 s UT (21:15:32.496).

The burst light curve shows several pulses with a total duration of ~70s.

As observed by Konus-Wind the burst
had a fluence of 6.29(-0.29, +0.31)x10^-5 erg/cm2,
and a 64-ms peak flux measured from T0+17.936 s
of (1.28 +/- 0.16)x10^-5 erg/cm2/s
(both in the 20 keV - 2 MeV energy range).

The time-integrated spectrum of the burst
(from T0 to T0+74.24 s) can be fitted (in the 20 keV-2 MeV range)
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with alpha = -1.51(-0.05, +0.04),
and Ep = 259(-27, +35) keV (chi2 = 64.5/59 dof).

All the quoted errors are at the 90% confidence level.

Assuming z = 1.03 (Thoene et al., GCN 7587) and a standard
cosmology model with H_0 = 70 km/s/Mpc, Omega_M = 0.27, Omega_\Lambda =
0.73, the isotropic energy release is E_iso ~1.81x10^53 erg,
the maximum luminosity is (L_iso)_max ~7.48x10^52 erg/s, and
Ep_rest ~524 keV.

The Konus-Wind light curve of this GRB is available
at http://www.ioffe.rssi.ru/LEA/GRBs/GRB080411_T76532/


GRB_name: GRB080411A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7590
SUBJECT: GRB 080411: Swift-XRT Refined Analysis 
DATE:    08/04/12 13:27:11 GMT
FROM:    Olivier Godet at U.of Leicester  <og19@star.le.ac.uk>

O. Godet, A. P. Beardmore, K. Page (U. Leicester) reports on behalf the Swift-XRT team: 

The XRT began observing the field of GRB 080411 (trigger=309010, Marshall et
al., GCN Circ. 7584) at 21:16:42 UT, 71 seconds after the BAT trigger.  We
analysed the first orbit of WT data (0.9 s) at T0+209s and the first 4 orbits
of PC data (~3.6 ks) from T0+4.2ks to T0+17.4ks.

The X-ray light-curve shows a broken power-law behaviour. Since there are 
no data between the WT and PC observations, it is difficult to constrain 
the initial decay and break time. The late decay from the PC data gives a 
decay slope of 0.98+/-0.05. Using ground data, we confirmed that the initial 
intense flux reported by Marshall et al. (GCN Circ. 7584) from the 0.1s image 
taken at T0+71s is real and is likely to correspond to the end of the activity 
observed in the BAT. That implies an initial rapid decay in the XRT light-curve.

The WT spectrum contains only 20 counts. So, the fitting parameters are not
well constrained when the spectrum is fitted by an absorbed power-law (N_H <
4.6e21 cm^-2 in excess with respect to the Galactic absorption along the burst
line of sight (5.7e20 cm^-2, Kalberla et al. 2005) and a photon index of 2.85
+1.54/-1.05).  The PC spectrum from T0+4.2ks to T0_17.4ks is fitted well by 
an absorbed power-law with a photon index of 2.14 +/- 0.09 and an absorption 
column of (1.5 +/- 0.3)e21 cm^-2, in excess with respect to the Galactic one.

The observed (unabsorbed) flux in the 0.3-10 keV band is 7.1e-10 (1.7e-9) erg
cm^-2 s^-1 for the WT spectrum and 7.2e-11 (1.1e-10) erg cm^-2 s^-1 for the PC
spectrum.

The predicted XRT count rate at T0+1d (T0+3d) is 0.26 (0.07) count s^-1, which
corresponds to an observed 0.3-10 keV flux of 2.7e-11 (7.1e-12) erg cm^-2 s^-1.

This is an official product of the Swift-XRT team.


GRB_name: GRB080411A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7591
SUBJECT: GRB 080411, Swift-BAT refined analysis
DATE:    08/04/12 14:32:04 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

G. Sato (GSFC/ISAS), S. D. Barthelmy (GSFC), W. Baumgartner (GSFC/UMBC),
J. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC),
H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), F. E. Marshall (GSFC),
K. McLean (GSFC/UMD), D. Palmer (LANL), T. Sakamoto (GSFC/UMBC),
M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-187 to T+723 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 080411 (trigger #309010)
(Marshall, et al., GCN Circ. 7584).  The BAT ground-calculated position is
RA, Dec = 37.961, -71.297 deg, which is 
   RA(J2000)  =  02h 31m 50.6s 
   Dec(J2000) = -71d 17' 49.6" 
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 86%.
 
The mask-weighted light curve shows two clusters of overlapping peaks.
The first starts at T+0.0 sec and rises to a peak in 1 sec.  The second peak
is at T+7 sec; the third at T+10 sec, and the 4th at T+19 sec at 25 cnt/cm2/sec
(15-150 keV).  The lightcurve returns to background before the beginning
of the second cluster of peaks.  The 5th peak starts at ~T+39 sec,
rises linearly, peaking at ~T+41 src at 43 cnts/cm2/sec.  There are two more
much smaller peaks at T+55 and T+64 sec.  The lightcurve returns to background
by ~T+95 sec.  There is a gap in the downlinked data from T+300 to T+420 sec.
It appears that the burst has returned to background well before this gap,
but should later downlinks show on-going activity, we will issue an updated
circular.  T90 (15-350 keV) is 56 +- 1 sec (estimated error including
systematics).
 
The time-averaged spectrum from T-0.0 to T+84.3 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.75 +- 0.03.  The fluence in the 15-150 keV band is 2.64 +- 0.01 x 10^-5 erg/cm2.
The 1-sec peak photon flux measured from T+40.45 sec in the 15-150 keV band
is 43.2 +- 0.9 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/309010/BA/


GRB_name: GRB080411A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7592
SUBJECT: GRB 080411: Swift/UVOT refined analysis
DATE:    08/04/12 15:22:49 GMT
FROM:    Andy Beardmore at U Leicester  <apb@star.le.ac.uk>

S. R. Oates and F. Marshall report on behalf of the Swift/UVOT team.

The Swift/UVOT observed the field of GRB 080411 starting at 4202s
after the BAT trigger (Marshall et al., GCN 7584).  We detect the
afterglow in white, v, b, u and uvw2 filters at the position:

RA(J2000)  =  02:31:55.19
DEC(J2000) = -71:18:07.30

with an etimated uncertainty of 0.5 arcsec (radius, 90% confidence).
This position is consistent with the optical afterglow position
reported by GROND (Kruehler et al., GCN 7586). The UVOT did not
perform observations in uvw1 and uvm2 filters. The following
magnitudes were obtained:

Filter    T_Mid(s)   Expo(s)            Magnitude
-----------------------------------------------------
White      4251        98              17.01 +/- 0.03
White      22869       295             18.09 +/- 0.03
v          16808       177             18.05 +/- 0.12
b          4615        197             17.43 +/- 0.05
b          21653       295             18.39 +/- 0.09
u          4410        197             16.46 +/- 0.04
uvw2       16260       886             18.41 +/- 0.07
-----------------------------------------------------

The above magnitudes are not corrected for the Galactic extinction
corresponding to a reddening of E_{B-V} = 0.04 mag (Schlegel et al.,
1998, ApJS, 500, 525). The photometry is on the UVOT flight system
described in Poole et al.  (2008, MNRAS, 383, 627).


GRB_name: GRB080413A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7593
SUBJECT: GRB 080413: ROTSE-III Detection of Optical Counterpart
DATE:    08/04/13 03:03:03 GMT
FROM:    Wiphu Rujopakarn at U AZ/Steward  <wiphu@as.arizona.edu>

GRB 080413: ROTSE-III Detection of Optical Counterpart

E.S. Rykoff (UCSB), W. Rujopakarn (Steward), report on behalf of the ROTSE
collaboration:

ROTSE-IIIc, located at the H.E.S.S. site at Mt. Gamsberg, Namibia,
responded to GRB 080413A (Swift trigger 309096). The first image was at
02:54:39.7 UT, 20.4 s after the burst (6.7 s after the GCN notice time).
The unfiltered images are calibrated relative to USNO A2.0. We detect a
12.8 magnitude, fading source with coordinates:

19:09:11.8 -27:40:41.6 (J2000), with positional uncertainty of 1' or better

start UT mag mlim(of image)
----------------------------------
02:54:39.7 12.8 15.3


This source is not visible in DSS (second epoch), 2MASS or the MPChecker
database.

A jpeg image is available at
http://www.rotse.net/images/gsb309096_3c00_img.jpg Note that the object
marked 7 is the candidate in question.

Continuing observations are in progress.


GRB_name: GRB080413A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7594
SUBJECT: GRB 080413: Swift detection of a burst with an optical afterglow
DATE:    08/04/13 03:06:53 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

A. P. Beardmore (U Leicester), D. N. Burrows (PSU),
P. A. Evans (U Leicester), N. Gehrels (NASA/GSFC),
S. T. Holland (CRESST/USRA/GSFC), S. D. Hunsberger (PSU),
J. A. Kennea (PSU), C. B. Markwardt (CRESST/GSFC/UMD),
K. L. Page (U Leicester), D. M. Palmer (LANL),
T. Sakamoto (NASA/UMBC), M. Stamatikos (NASA/ORAU) and
E. Troja (U Leicester/INAF-IASFPA) report on behalf of the Swift
Team:

At 02:54:19 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 080413 (trigger=309096).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 287.290, -27.679 which is 
   RA(J2000) = 19h 09m 10s
   Dec(J2000) = -27d 40' 44"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a triple-peaked
structure with a duration of about 55 sec.  The peak count rate
was ~10000 counts/sec (15-350 keV), at ~1 sec after the trigger. 

The XRT began observing the field at 02:55:20.0 UT, 60.7 seconds after
the BAT trigger. XRT found a bright, fading uncatalogued X-ray source
located at RA, Dec 287.2978, -27.6779 which is equivalent to:
   RA(J2000)  = 19h 09m 11.4s
   Dec(J2000) = -27d 40' 40.4"
with an uncertainty of 4.7 arcseconds (radius, 90% containment). This
location is 25 arcseconds from the BAT onboard position, within the BAT
error circle. No event data are yet available to assess possible
redshift constraints using X-ray spectroscopy and the nH-z relation
from Grupe et al. (2007). 


UVOT took a finding chart exposure of 100 seconds with the White (160-650 nm)
filter starting 76 seconds after the BAT trigger. There is a candidate
afterglow in the rapidly available 2.7'x2.7' sub-image at
  RA(J2000)  = 19:09:11.76 = 287.2990
  DEC(J2000) = -27:40:40.1  = -27.6778
with a 1-sigma error radius of about 0.6 arc sec. This position is 3.9 arc sec. 
from the center of the XRT error circle. The estimated magnitude is 15.2 with a
1-sigma error of about 0.5 mag. No correction has been made for the expected
extinction corresponding to E(B-V) of 0.16. 


GRB_name: GRB080413A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7595
SUBJECT: GRB 080413: TAROT Calern observatory optical observations
DATE:    08/04/13 03:54:16 GMT
FROM:    Alain Klotz at CESR-CNRS  <Alain.Klotz@free.fr>

Klotz, A. (CESR-OMP), Boer M. (OHP), Atteia J.L. (LATT-OMP) report:

We imaged the field of GRB 080413 detected by SWIFT
(trigger 309096) with the TAROT robotic telescope (D=25cm)
located at the Calern observatory, France.

The observations started 21.8s after the GRB trigger
(8.3s after the notice). The elevation of the field increased from
from 11 degrees above horizon and weather conditions
were poor at the beginning of observations. The first
image showing stars started 480s after the trigger.

We detected the candidate couterpart mentioned by Rykoff
et al. (GCNC 7593) at the following position (+/- 2 arcsec):

RA(J2000) = 19h 09m 11.85s
DEC(J2000) -27d 40' 43.0"

Unfiltered magnitudes are:
t0+480s to t0+570s : R > 12.5
t0+1174s to t0+1263s : R = 15.0 +/- 0.2
t0+1470s to t0+1650s : R = 15.3 +/- 0.2
t0+2035s to t0+2215s : R = 15.5 +/- 0.2


Magnitudes were estimated with the nearby USNO-B1 stars
and are not corrected for galactic dust extinction.

N.B. Galactic coordinates are lon=  9.5236 lat=-15.8249
and the galactic extinction in R band is 2.4 magnitudes
estimated from D. Schlegel et al. 1998ApJ...500..525S.

This message may be cited.


GRB_name: GRB080413A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7596
SUBJECT: GRB 080413: Enhanced Swift-XRT position
DATE:    08/04/13 06:42:02 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 176 s of overlapping XRT Photon Counting mode and UVOT
data for GRB 080413, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 287.29829, -27.67807 which is equivalent
to:

RA (J2000): 19h 09m 11.59s
Dec (J2000): -27d 40' 41.1"

with an uncertainty of 2.3 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest position
can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is
described by Goad et al. (2007, A&A, 476, 1401
http://www.swift.ac.uk/xrt_positions/Goad.pdf), the current algorithm is an
extension of this method.

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB080413A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7597
SUBJECT: GRB 080413A: REM detection of the NIR Afterglow
DATE:    08/04/13 09:06:15 GMT
FROM:    Angelo Antonelli at Obs. Astro. di Roma  <a.antonelli@oa-roma.inaf.it>

L.A. Antonelli, P. D'Avanzo, D. Malesani, S. Covino, D. Fugazza, L.  
Calzoletti, S. Campana, G. Chincarini, M.L. Conciatore, S. Cutini, V.  
D'Elia, F. D'Alessio, F. Fiore, P. Goldoni, D. Guetta, C. Guidorzi,  
G.L. Israel, E. Maiorano, N. Masetti, A. Melandri, E.J.A. Meurs, L.  
Nicastro, E. Palazzi, E. Pian, F. Piranomonte, S. Piranomonte, L.  
Stella, G. Stratta, G. Tagliaferri, G. Tosti, V. Testa, S.D. Vergani,  
and F. Vitali, report on behalf of the REM team:

The robotic 60-cm REM telescope located at La Silla (Chile) observed  
automatically the field of the GRB 080413A (Beardmore et al., GCN  
7594) starting about 1.3 hours after the burst due to object  
visibility constraints.
Observation started as soon as the object is risen so the Airmass was  
large.

A preliminary investigation of our earliest images (R,z,J,H,K) showed  
that the candidate optical counterpart (Rykoff et al. GCN 7593,  
Beardmore et al., GCN 7594, Klotz et al., GCN 7595) is observed in  
all bands. At the beginning of REM observation, the object had a H  
mag of about H=15.2 calibrated against 2MASS and not corrected for  
galactic extinction.

This message may be cited.


GRB_name: GRB080413B
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7598
SUBJECT: GRB 080413B: Swift detection of a possibly short burst with optical counterpart
DATE:    08/04/13 09:20:28 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

M. Stamatikos (NASA/ORAU), A. P. Beardmore (U Leicester),
N. Gehrels (NASA/GSFC), S. D. Hunsberger (PSU),
C. B. Markwardt (CRESST/GSFC/UMD), J. P. Osborne (U Leicester),
K. L. Page (U Leicester), D. M. Palmer (LANL),
T. Sakamoto (NASA/UMBC), R. L. C. Starling (U Leicester) and
E. Troja (U Leicester/INAF-IASFPA) report on behalf of the Swift
Team:

At 08:51:12 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 080413B (trigger=309111).  Swift started slewing approximately 
70 seconds after the burst. The BAT on-board calculated location is 
RA, Dec 326.134, -19.969 which is 
   RA(J2000) = 21h 44m 32s
   Dec(J2000) = -19d 58' 08"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a single peaked
structure with a duration of about 3 sec.  The peak count rate
was ~15,000 counts/sec (15-350 keV), at ~0.2 sec after the trigger. 

The XRT began observing the field at 08:53:23.8 UT, 131.2 seconds after
the BAT trigger. Using promptly downlinked data we find a fading,
uncatalogued X-ray source with an enhanced position: RA, Dec 326.14434,
-19.98104 which is equivalent to:
   RA(J2000)  = 21h 44m 34.64s
   Dec(J2000) = -19d 58' 51.7"
with an uncertainty of 2.6 arcseconds (radius, 90% containment). This
location is 55 arcseconds from the BAT onboard position, within the BAT
error circle. 

A power-law fit to a spectrum formed from promptly downlinked event
data does not constrain the column density, so we cannot provide limits
on the redshift using spectroscopy and the relation from Grupe et al. 
(2007). A summary of the promptly downlinked data is given at
http://www.swift.ac.uk/sper/309111/. 

UVOT took a finding chart exposure of 100 seconds with the White (160-650 nm)
filter starting 134 seconds after the BAT trigger. There is a candidate
afterglow in the rapidly available 2.7'x2.7' sub-image at
  RA(J2000)  = 21:44:34.68 = 326.1445
  DEC(J2000) = -19:58:52.0  = -19.9811
with a 1-sigma error radius of about 0.6 arc sec. This position is 0.6 arc
sec. from the XRT position. The estimated magnitude is 16.5
with a 1-sigma error of about 0.5 mag. No correction has been made for the
expected extinction corresponding to E(B-V) of 0.04. 

Burst Advocate for this burst is M. Stamatikos (michael AT milkyway.gsfc.nasa.gov). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB080413B
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7599
SUBJECT: GRB 080413B: GROND detection of afterglow in all bands
DATE:    08/04/13 09:32:15 GMT
FROM:    Jochen Greiner at MPI  <jcg@mpe.mpg.de>

T. Kruehler, J. Greiner, A. Kupcu Yoldas, C. Clemens, A. Yoldas (all MPE
Garching) and G. Szokoly (Eoetvoes Univ. Budapest and MPE Garching)
report on behalf of the GROND team:

We observed the field of GRB 080413B detected by Swift/BAT (trigger 309111,
Stamatikos et al. 2008, GCN Circ. 7598) simultaneously in g'r'i'z'JHK 
with GROND mounted at the 2.2m ESO/MPI telescope at La Silla Observatory 
(Chile). Observations started at 08:56 UT on April 13th, 2008, 5 min after
the burst.

We detect a new bright point source at

RA (J2000) = 21:44:34.67
DEC (J2000) = -19:58:52.4

with an uncertainty of 0.5", which is consistent with the UVOT
position.

The object is detected in all seven bands, implying a redshift
smaller than 3.5.

Preliminary photometry of the first 4 min exposure yields an J band 
magnitude of 16.5 calibrated against 2MASS field stars.
The given magnitude is not corrected for the Galactic foreground
reddening of E(B-V)=0.04 mag (Schlegel et al., 1998).


GRB_name: GRB080413B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7600
SUBJECT: GRB080413B: REM NIR & Optical Observation
DATE:    08/04/13 10:06:45 GMT
FROM:    Angelo Antonelli at Obs. Astro. di Roma  <a.antonelli@oa-roma.inaf.it>

L.A. Antonelli, S. Covino, P. D'Avanzo, D. Fugazza, L.  Calzoletti,   
S. Campana, G.  Chincarini, M.L. Conciatore, S. Cutini, V. D'Elia, F.  
D'Alessio, F.  Fiore, P. Goldoni, D. Guetta,  C. Guidorzi, G.L.    
Israel, E. Maiorano, N. Masetti, A. Melandri, E. Meurs, L. Nicastro,  
E. Palazzi, E. Pian, S. Piranomonte, L.  Stella, G.  Stratta, G.   
Tagliaferri, G. Tosti, V.Testa, S.D. Vergani,  F. Vitali report on   
behalf of the REM team:

The robotic 60-cm REM telescope located at La Silla (Chile) observed  
automatically the field of the GRB 080413B on April 13 08:52:43 UT   
(about 91 seconds after the burst).

The afterglow reported in GCN 7598, 7599 (Stamatikos et al., Kruehler  
et al.) is well detected in our early images at about H~14.3.

Further analyses and observations are in progress.


GRB_name: GRB080413B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7601
SUBJECT: GRB 080413B: VLT redshift
DATE:    08/04/13 10:58:47 GMT
FROM:    Daniele Malesani at Niels Bohr Inst,Dark Cosmology Center  <malesani@astro.ku.dk>

Paul M. Vreeswijk, Christina C. Thoene, Daniele Malesani, Johan P. U. 
Fynbo, Jens Hjorth (DARK/NBI), Pall Jakobsson (Univ. Hertfordshire), 
Nial R. Tanvir (Univ. Leicester), and Andrew J. Levan (Univ. Warwick), 
report on behalf of a larger collaboration:

We observed the afterglow of the possibly short GRB 080413B (Stamatikos 
et al., GCN 7598) with the ESO VLT equipped with FORS1. A 600 s spectrum 
centered on Apr 13.403 UT (49.5 min after the GRB) was acquired covering 
the range 3500-9000 AA.

 From detection of numerous absorption features, including Fe II, Mg II 
and Mg I lines, we infer a redshift z = 1.10. In particular, we detect 
the Fe II 2396 fine-structure line, which confirms this redshift is very 
likely that of the host of the GRB.

We acknowledge excellent support from the VLT staff, particularly Thomas 
Szeifert, Jose Cortes, and Gianni Marconi.


GRB_name: GRB080413A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7602
SUBJECT: GRB 080413A: VLT/UVES redshift
DATE:    08/04/13 12:10:21 GMT
FROM:    Christina Thoene at Niels Bohr Institute,DARK Cosmo Ctr  <cthoene@astro.ku.dk>

Christina C. Thoene, Daniele Malesani, Paul M. Vreeswijk, Johan P. U.
Fynbo (DARK/NBI), Pall Jakobsson (Univ. of Hertfordshire), Cedric Ledoux
and Alain Smette (ESO) report on behalf of a larger collaboration:

We observed the afterglow of GRB 080413A (GCN 7593, Rykoff & Rujopakarn;
GCN 7594, Stamatikos et al.) on Apr. 13 starting UT 06:36 with UVES at the
VLT. Spectra of 2700 s with low S/N were acquired in the DIC 2R and
2B settings covering the wavelength range between 3250 and 9000 AA.
We detect several narrow absorption features including SII, Si II, CII,
Fe II, AlII, C IV, Si IV as well as broad Lyman alpha absorption at the
highest redshift system which has z=2.433 and is very likely the redshift
of GRB 080413A.

We thank the Paranal staff for executing the observations, in particular
Swetlana Hubrig and Jose Cortes.


GRB_name: GRB080413A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7603
SUBJECT: GRB 080413A Bootes observation
DATE:    08/04/13 12:50:49 GMT
FROM:    Petr Kubanek at AIO  <petr@lascaux.asu.cas.cz>

P. Kubanek, M. Jelinek, J. Gorosabel, A. J. Castro-Tirado (IAA-CSIC
Granada), L. Sabau-Graziati (INTA Madrid), A. de Ugarte Postigo (ESO
Santiago), R. Hudec (ASU-CAS Ondrejov), P. Perez-Gonzalez and J.
Zamorano (UCM Madrid) report on behalf of a larger collaboration:

The BOOTES-1 0.3m telescope in South Spain observed GRB 080413A,
starting at 02:55:20 UT (46 sec after receiving trigger, 1 minute after
GRB). A sequence of preprogrammed 6 sec, 20 and 60 sec exposures was
obtained. The optical counterpart reported by Rykoff at al. (GCN
7593) is clearly detected on the initial exposures.

Further data were obtained at the 2.5m NOTin La Palma under non-optimal
conditions.


GRB_name: GRB080413A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7604
SUBJECT: GRB 080413A, Swift-BAT refined analysis
DATE:    08/04/13 15:58:16 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

J. Tueller (GSFC), S. D. Barthelmy (GSFC), W. Baumgartner (GSFC/UMBC),
A. P. Beardmore (U Leicester), J. Cummings (GSFC/UMBC), E. Fenimore (LANL),
N. Gehrels (GSFC), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD),
K. McLean (GSFC/UMD), D. Palmer (LANL), T. Sakamoto (GSFC/UMBC),
G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU), T. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-239 to T+454 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 080413A (trigger #309096)
(Beardmore, et al., GCN Circ. 7594).  The BAT ground-calculated position is
RA, Dec = 287.301, -27.677 deg, which is 
   RA(J2000)  =  19h 09m 12.1s 
   Dec(J2000) = -27d 40' 36.8" 
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 81%.
 
The mask-weighted light curve shows four peaks.  The first starting at T-0.1 sec,
peaking at T+2.0 sec.  The second peak overlaps with the first and peaks
at ~T+7 sec.  The third and fourth peaks are well separated with peaks
at T+16 and T+47 sec, repsectively.  The lightcurve returns to baseline
at ~T+80 sec.  T90 (15-350 keV) is 46 +- 1 sec (estimated error
including systematics).
 
The time-averaged spectrum from T-0.1 to T+50.3 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.57 +- 0.06.  The fluence in the 15-150 keV band is 3.5 +- 0.1 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+1.64 sec in the 15-150 keV band
is 5.6 +- 0.2 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/309096/BA/


GRB_name: GRB080413A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7605
SUBJECT: GRB 080413A: Swift-XRT refined analysis
DATE:    08/04/13 16:39:02 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P.A. Evans, K.L. Page, A.P. Beardmore, R.L.C. Starling (U. Leicester)
and F.E. Marshall (NASA/GSFC) report on behalf of the Swift-XRT team:

We have analysed 5.2 ks of Swift XRT data for GRB 080413A (Beardmore et
al. GCN Circ. 7594), from T0+67 s to T0+21000 s. The first 186 s of data
were obtained in Windowed Timing (WT mode); the remainder in Photon
Counting mode. The best XRT position for this object is the
UVOT-enhanced position given in Osborne et al. (GCN Circ. 7596).

The X-ray light curve is well fitted by a power-law decay, with an
initial decay slope of 2.87 (+/- 0.19) up to T0+175 (+23/-16) s, at
which point the decay shallows to a slope of 1.10 (+0.06/-0.07).

A spectrum obtained from all of the WT mode data can be modelled with an
absorbed power-law with a photon index gamma=3.12 (+0.16/-0.15). A
redshifted absorbing column of 1.53 (+0.43/-0.38) x 10^22 cm^-2, at a
redshift of z=2.433 (Thoene et al. GCN Circ 7602) is necessary in
addition to the Galactic column of 8.71 x 10^20 cm^-2 (Kalberla et al.
2005). The observed (unabsorbed) 0.3-10 keV flux in this spectrum is
4.1 x 10^-10 (1.71 x 10^-9) erg cm^-2 s^-1.

If the source continues to decay at the present rate, we predict a count
rate of 3.51 x 10^-3 count/sec at T0+24 hours, which correponds to a
0.3-10 keV observed (unabsorbed) flux of 9.54 x 10^-14 (2.72 x 10^-13)
erg cms^-2 s^-1.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB080413B
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7606
SUBJECT: GRB 080413B, Swift-BAT refined analysis
DATE:    08/04/13 17:27:57 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

S. D. Barthelmy (GSFC), W. Baumgartner (GSFC/UMBC), J. Cummings (GSFC/UMBC),
E. Fenimore (LANL), N. Gehrels (GSFC), H. Krimm (GSFC/USRA),
C. Markwardt (GSFC/UMD), K. McLean (GSFC/UMD), D. Palmer (LANL),
T. Sakamoto (GSFC/UMBC), G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU),
J. Tueller (GSFC), T. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-119 to T+148 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 080413B (trigger #309111)
(Stamatikos, et al., GCN Circ. 7598).  The BAT ground-calculated position is
RA, Dec = 326.138, -19.981 deg, which is 
   RA(J2000)  =  21h 44m 33.1s 
   Dec(J2000) = -19d 58' 49.8" 
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 20%.
 
The mask-weighted light curve shows a single FRED-like peak starting 
at T-1.1 sec, peaking at T+0.2 sec, and returning to baseline at ~T+30 sec.
T90 (15-350 keV) is 8.0 +- 1.0 sec (estimated error including systematics).
 
The time-averaged spectrum from T-1.3 to T+10.7 sec is best fit by a power law
with an exponential cutoff.  This fit gives a photon index 1.26 +- 0.27, 
and Epeak of 73.3 +- 15.8 keV (chi squared 32.60 for 56 d.o.f.).  For this
model the total fluence in the 15-150 keV band is 3.2 +- 0.1 x 10^-6 erg/cm2
and the 1-sec peak flux measured from T-0.26 sec in the 15-150 keV band is
18.7 +- 0.8 ph/cm2/sec.  A fit to a simple power law gives a photon index
of 1.80 +- 0.06 (chi squared 45.07 for 57 d.o.f.).  All the quoted errors
are at the 90% confidence level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/309111/BA/


GRB_name: GRB080413A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7607
SUBJECT: GRB080413A: Swift/UVOT observations
DATE:    08/04/13 17:49:17 GMT
FROM:    Samantha Oates at MSSL  <sro@mssl.ucl.ac.uk>

S. R. Oates and F. E. Marshall report on behalf of the Swift/UVOT team.

The Swift/UVOT observed the field of GRB 080413A starting at 77s after 
the BAT
trigger (Beardmore et al., GCN 7594). We detect the afterglow in 
white,v,b and
u filters at the position:

RA(J2000)  =   19:09:11.76
DEC(J2000) =  -27:40:40.27

with an estimated uncertainty of 0.5 arcsec (radius, 90% confidence). 
This position is
consistent with the enhanced XRT position and the position reported by 
ROSTE-III
(Rykoff et al., GCN 7593).

The magnitudes and 3 sigma upper limits are reported below:

Filter    T_Mid(s)   Expo(s)          Magnitude/3sigUL
-----------------------------------------------------
White     126          98               15.37 +/- 0.01
White     5478         197              19.74 +/- 0.17
v         268          169              15.08 +/- 0.03
v         5888         197              19.16 +/- 0.51
b         5273         197              19.33 +/- 0.21
u         5068         197              19.05 +/- 0.22
w1        4863         197              >19.55
m2        4658         197              >19.48
w2        5684         197              >19.57
-----------------------------------------------------

The above magnitudes are not corrected for the Galactic extinction 
corresponding to a
reddening of E_{B-V} = 0.16 mag (Schlegel et al., 1998, ApJS, 500, 525). 
The photometry
is on the UVOT flight system described in Poole et al. (2008,MNRAS,383,627).


GRB_name: GRB080413B
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7608
SUBJECT: GRB 080413B: Swift XRT refined analysis
DATE:    08/04/13 18:55:01 GMT
FROM:    Eleonora Troja at INAF-IASFPA  <nora@ifc.inaf.it>

E. Troja (U. Leicester/INAF-IASFPa) and M. Stamatikos (NASA/ORAU)
report on behalf of the Swift-XRT team:

We have analysed 9.9 ks of Swift XRT data for GRB 080413B (Stamatikos et
al. GCN Circ. 7598), from T0+134 s to T0+20.1 ks. 
The data set consists of 376 s exposure in Windowed Timing (WT) mode 
followed by 9.5 ks exposure in Photon Counting (PC) mode.

By using orbits 2-4 of PC data [from T0+6.0 ks to T0+20.1 ks]
in order to avoid pile-up effects, we derive an XRT refined position 

     RA (2000) = 21h 44m 34.43s  = 326.1435 d
     Dec (2000) = -19d 58' 52.9" = -19.9814 d

with an uncertainty of 3.7 arcsec (90% containment). This position
is 3.6 arcsec from the UVOT candidate afterglow (GCN Circ. 7598), 
and 3.4 arcsec from the source reported in Kruehler et al. (GCN Circ.
7599).

The X-ray light curve is well fitted by a simple power-law, with a 
decay slope of 0.88 +/- 0.06.

A spectrum obtained from the WT mode data, from T0+135 s to T0+511 s,
can be modelled with an absorbed power-law with a photon index of 
2.05 +/- 0.10 , and a redshifted absorbing column of (0.32 +/- 0.13) 
x 10^22 cm^-2 at a redshift of z=1.1 (Vreeswijk et al. GCN Circ 7601) 
in addition to the Galactic column of 3.06 x 10^20 cm^-2 (Kalberla et 
al. 2005). The observed (unabsorbed) 0.3-10 keV flux in this spectrum is
1.79 x 10^-10 (2.13 x 10^-10) erg/cm^2/s. 
The PC spectrum of the first four orbits, from T0+512 s to T0+20.1 ks, 
can be fit by an absorbed power-law model with photon index 1.93 +/-
0.08 and a column density consistent with the WT spectrum. 
All the reported errors are at the 90% confidence level.

If the source continues to decay at the present rate, we predict a count
rate of 0.035 count/sec at T0+24 hours, which corresponds to a 0.3-10 keV 
observed (unabsorbed) flux of 1.6 x 10^-12 (1.8 x 10^-12) erg/cm^2/s.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB080413A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7609
SUBJECT: GRB 080413a, SMARTS optical/IR afterglow observations
DATE:    08/04/13 19:22:38 GMT
FROM:    Bethany Cobb at Yale U  <cobb@astro.yale.edu>

B. E. Cobb (Yale), part of the larger SMARTS consortium, reports:

Using the ANDICAM instrument on the 1.3m telescope at CTIO, we
obtained optical/IR imaging of the error region of GRB 080413a
(GCN 7594, Beardmore et al.), starting at 2008-04-13 05:48 UT,
which is ~2.9 hours post-burst. Several dithered images were obtained
in each filter, with total summed exposure times of 180s in each of
BRIYJK and 120s in each of H and V.

The GRB afterglow (GCN 7593 Rykoff & Rujopakarn; GCN 7594,
Beardmore et al.) is detected in all our images.  At
a mid-exposure time of 2008-04-13 06:02 (~3.1 hours post-burst)
the afterglow has the following magnitudes (which have not been
corrected for Galactic reddening):

B= 20.88 +/- 0.10
V= 20.25 +/- 0.11
R= 19.25 +/- 0.05
I= 18.84 +/- 0.06
J= 18.23 +/- 0.23
H= 17.05 +/- 0.15
K= 16.19 +/- 0.12

Optical photometry is calibrated against Landolt standard stars
and IR photometry is calibrated against 2MASS stars in the field.

Between 3.1 and 5.1 hours post burst, the afterglow decays
by ~0.75 magnitudes, indicating an approximate decay rate of alpha = -1.4
(where afterglow flux is proportional to t^alpha).


GRB_name: GRB080413B
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7610
SUBJECT: Swift-BAT spectral lag analysis of GRB 080413B
DATE:    08/04/13 19:59:34 GMT
FROM:    Michael Stamatikos at GSFC  <michael.stamatikos-1@nasa.gov>

T. Sakamoto (GSFC/UMBC), T. Ukwatta (GWU), M. Stamatikos (GSFC/ORAU), S. D.
Barthelmy (GSFC), N. Gehrels (GSFC),

We further report on additional spectral lag analysis regarding the possible
short duration burst classification of GRB 080413B (Stamatikos et al. GCN
Circ. 7598). We now believe GRB 080413B to be a long GRB based upon the
following BAT prompt emission properties:

1) The spectral lag in 25-50 to 100-350 keV bands and 15-25 to 50-100 keV
bands are 0.238 +- 0.016 sec and 0.136 +- 0.008 sec for 4 ms binning.
Therefore, GRB 080413B shows a significant lag.

2) The T90 of the spike is 8.0 +- 1.0 sec based on the mask-weighted light
curve (Barthelmy et al., GCN 7606), which is well within the long duration
GRB population (Sakamoto et al. ApJS, 175, 179).


GRB_name: GRB080413B
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7611
SUBJECT: GRB080413B
DATE:    08/04/13 20:38:00 GMT
FROM:    Samantha Oates at MSSL  <sro@mssl.ucl.ac.uk>

S. R. Oates and M. Stamatikos report on behalf of the Swift/UVOT team.

The Swift/UVOT began settled observations of the field of GRB 080413B 135s
after the BAT trigger (Stamatikos et al., GCN 7598). We detect the 
afterglow
in the 7 UVOT filters at the position:

RA(J2000)  =  21:44:34.65
DEC(J2000) = -19:58:52.40

with an estimated uncertainty of 0.5 arcsec (radius, 90% confidence). 
This position is
consistent with the refined XRT position and the GROND optical position 
(Kruehler et al., GCN 7599).

The magnitudes are reported below:

Filter    T_Mid(s)   Expo(s)               Magnitude
-------------------------------------------------------
White       184       98                 16.67  0.02
White       740       10                 17.67  0.15
v           440       393                17.64  0.10
v           1183      393                18.64  0.22
b           727       10                 18.82  0.71
u           796       19                 17.67  0.27
w1          682       19                 17.42  0.27
m2          810       19                 18.07  0.47
w2          762       19                 17.92  0.36
-------------------------------------------------------

The above magnitudes are not corrected for the Galactic extinction 
corresponding to a
reddening of E_{B-V} = 0.04 mag (Schlegel et al., 1998, ApJS, 500, 525). 
The photometry
is on the UVOT flight system described in Poole et al. 
(2008,MNRAS,383,627).


GRB_name: GRB080413B
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7612
SUBJECT: GRB 080413B: Ep,i-Eiso correlation
DATE:    08/04/13 22:47:19 GMT
FROM:    Lorenzo Amati at INAF-IASF/Bologna  <amati@iasfbo.inaf.it>

L. Amati (INAF - IASF Bologna),

By assuming the VLT redshift of 1.10 (Vreeswijk et al., GCN 7601), the 
values of spectral parameters alpha and Ep, and the fluence, provided 
by Swift/BAT (Barthelmy et al., GCN 7606), a value of spectral parameter 
beta of -2.3 and a Lambda-CDM cosmology with H0=70 km/s/Mpc, Omega_M=0.27 
and Omega_Lambda=0.73, the values of Ep,i and Eiso (1-10000 keV 
cosmological rest-frame) of GRB 080413B are approximately 150+/30 keV and 
(2.4+/-0.2)x10^52 erg, fully consistent with the Ep,i-Eiso correlation.

Given that this correlation holds for long GRBs only (see, e.g., Amati, 
MNRAS, 2006; Amati, astroph/0611189), this is a further evidence that
GRB 080412B is not a short GRB.

This message may be cited.


GRB_name: GRB080413A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7614
SUBJECT: VLA radio observations of GRB 080413A
DATE:    08/04/14 14:33:02 GMT
FROM:    Poonam Chandra at U Virginia/NRAO  <pc8s@virginia.edu>

Poonam Chandra (NRAO/UVA) and Dale A. Frail (NRAO) report on behalf
of the Caltech-NRAO-Carnegie GRB Collaboration:



"We used the Very Large Array to observe the field of view toward GRB
080413A (GCN 7594) at a frequency of 8.46 GHz at 2008 April 14.53 UT.
 We do not detect the GRB afterglow at the ROTSE optical position (GCN 
7593).
The flux density at the  GRB afterglow position is -61 +/- 49 uJy.

The National Radio Astronomy Observatory is a facility of the National
Science Foundation operated under cooperative agreement by Associated
Universities, Inc."


GRB_name: GRB080413B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7615
SUBJECT: GRB 080413B: Gemini-South Spectroscopy
DATE:    08/04/14 16:42:35 GMT
FROM:    Antonino Cucchiara at PSU  <cucchiara@astro.psu.edu>

A. Cucchiara and D. B. Fox (Penn State) with S. B. Cenko (Caltech),
report on behalf of a larger collaboration: 

"Starting on 2008 April 13.41 UT we observed GRB 080413B (Stamatikos
et al. GCN 7598) with the GMOS spectrograph on the Gemini South
telescope.  We obtained a single 900-sec spectrum in the wavelength
range 3900-6700A.  The resolution of our spectrum is 5 Ang/pixel (R ~
1100 at 5900A).  We clearly observe several metal absorption features
corresponding to the MgII doublet (2796,2803 A), MgI (2853A), FeII
(2586A and 2600A), and FeI (3021A). These identifications are
consistent with a host galaxy redshift of z = 1.10, confirming the
result reported from VLT observations by Vreeswijk et al.(GCN 7601)."


GRB_name: GRB080413A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7616
SUBJECT: GRB 080413A: Gemini-South Spectroscopy
DATE:    08/04/14 17:27:38 GMT
FROM:    Antonino Cucchiara at PSU  <cucchiara@astro.psu.edu>

A. Cucchiara and D. B. Fox (Penn State) with S. B. Cenko (Caltech),
report on behalf of a larger collaboration:

"Starting on 2008 April 13.27 UT we observed GRB 080413A (GCN 7593 and
7594) with the GMOS spectrograph on the Gemini South telescope. We
obtained 2x1200-sec spectra in the wavelength range 3900-8000A. The
resolution of our spectrum is 5.2 Ang/pixel (R ~1200 at 6000A). We
clearly observe several metal absorption features corresponding to the
SiIV (1393,1402 A), CIV (1548, 1550A), SiII (1526A), and AlII (1670A)
transitions.  A Lyman break is also present at the blue edge of our
spectra (~ 4170A).  These identifications are consistent with a host
galaxy redshift of z = 2.43, confirming the result reported from VLT
observations by Thoene et al.(GCN 7602)."


GRB_name: GRB080413B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7617
SUBJECT: VLA radio observations of GRB 080413B
DATE:    08/04/14 17:34:10 GMT
FROM:    Poonam Chandra at U Virginia/NRAO  <pc8s@virginia.edu>

Poonam Chandra (NRAO/UVA) and Dale A. Frail (NRAO) report on behalf
of the Caltech-NRAO-Carnegie GRB Collaboration:



"We used the Very Large Array to observe the field of view toward GRB
080413B (GCN 7598) at a frequency of 8.46 GHz at 2008 April 14.59 UT.
 We do not detect the GRB afterglow at the GROUND optical position (GCN 
7599). The flux density at the  GRB afterglow position is 86  36 uJy.

The National Radio Astronomy Observatory is a facility of the National
Science Foundation operated under cooperative agreement by Associated
Universities, Inc."


GRB_name: GRB080414A
Detection_method: INTEGRAL
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7618
SUBJECT: GRB 080414: A long GRB detected by INTEGRAL
DATE:    08/04/15 00:12:07 GMT
FROM:    Sandro Mereghetti at IASF/CNR  <sandro@iasf-milano.inaf.it>

S.Mereghetti, A.Paizis (IASF-Milano), D.Gotz (CEA-Saclay), M. Turler, 
S.Shaw, M. Beck, C. Baldovin Saavedra (ISDC, Versoix), and J. 
Borkowski (CAMK, Torun) on behalf of the IBAS Localization Team report:

A GRB lasting about 10 s has been detected by IBAS in IBIS/ISGRI data at 
22:33:32 UT of April 14. The coordinates (J2000)  are:

 RA:  272.1342 [degrees]
 DEC: -18.8291 [degrees]

with an uncertainty of 2 arcmin (90% c.l.).

A preliminary analysis gives a peak flux in the 20-200 keV range of about 
1 ph/cmq/s (1-s integration time) and a fluence over the same energy range 
of 3e-7 erg/cmq.

This message can be cited.


GRB_name: GRB080414A
Detection_method: INTEGRAL
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7619
SUBJECT: GRB 080414 Watcher observations
DATE:    08/04/15 00:24:55 GMT
FROM:    Petr Kubanek at AIO  <petr@lascaux.asu.cas.cz>

P. Kubanek (IAA-CSIC Granada, GACE Valencia) and J. French (UCD Dublin)
reports on behalf of the Watcher collaboration:

Watcher started observations of long INTEGRAL GRB at 22:36:25, e.g. 2:50
post GRB, 33 sec post GCN trigger. Observation, as well as futher
analysis, is ongoing. Quick look on first images does not show any new
source down to 14 mag.

This message may be cited.


GRB_name: GRB080414A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7620
SUBJECT: GRB 080414: RTT150 optical observations
DATE:    08/04/15 01:26:35 GMT
FROM:    Rodion Burenin at IKI, Moscow  <rodion@hea.iki.rssi.ru>

R. Burenin, (IKI), I. Khamitov (TUG), M. Pavlinsky, R. Sunyaev (IKI),  
Z. Eker (TUG), U. Kiziloglu (METU), E. Gogus (Sabanci Uni.),
I. Bikmaev, N. Sakhibullin (KSU/AST)

report:

The field of the long GRB 080414 detected by INTEGRAL (Mereghetti et al.,
GCN 7618) was observed with Russian-Turkish 1.5-m telescope (RTT150,
Bakirlitepe, TUBITAK National Observatory, Turkey), under not optimal
conditions. We made 8x100s images in R band centered at 23:46 UT,
i.e. approximately 1.21 hours after the burst. We detect no new objects as
compared to DSS-II red plate with magnitude brighter than R=~20.


GRB_name: GRB080319B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7621
SUBJECT: GRB 080319B: Continued Gemini-N monitoring
DATE:    08/04/15 22:36:51 GMT
FROM:    Nial Tanvir at IofA U.Cambridge  <nrt@ast.cam.ac.uk>

N. R. Tanvir (U. Leicester), D. A. Perley (UC Berkeley),
A. J. Levan (U. Warwick), J. S. Bloom (UC Berkeley),
A. S. Fruchter (STScI) and E. Rol (U. Leicester) report:

We obtained a further epoch of observations of GRB 080319B with
Gemini-North/GMOS on April 14 UT. These observations yielded the
following magnitudes: g=25.80+/-0.09, r=24.93+/-0.07, i=24.22+/-0.05.

Although the r-band magnitude is consistent with a continued power-law
decline in flux, the source is now clearly much redder than it was at
early times, suggesting it is likely contaminated by light from a host
galaxy and/or associated supernova.  The g-band observation, which
would be less contaminated by any SN light, indicates a steeper
decline which may be consistent with a break in the underlying
afterglow light curve (GCN 7567).

The absence of any extended emission in the previous HST observations
(GCN 7569) argues against a significant host contribution, although a very
compact host is not ruled out.

Further analysis is ongoing.

We thank Gemini staff astronomers, particularly Sandy Leggett, for
their support in obtaining these observations.


GRB_name: GRB080413A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7622
SUBJECT: GRB 080413A: MOA-II optical afterglow observations
DATE:    08/04/15 23:48:14 GMT
FROM:    Nobuyuki Kawai at Tokyo Tech  <nkawai@hp.phys.titech.ac.jp>

A. Fukui, Y. Itow, T. Sumi (STE Lab, Nagoya Univ.), and P. Tristram
(Canterbury Univ.)  on behalf of the MOA Collabration (Bond et
al. 2001, Sumi et al. 2003) report:

We observed the optical afterglow of GRB080413A (GCN 7593, Rykoff &  
Rujopakarn; GCN 7594, Beardmore et al.) on Apr. 13 between  
12:29:16.4 UTC and 14:13:06.6 UTC, corresponding to about 9.5-11 h  
after the burst, with the 1.8m MOA-II telescope at Mt. John  
observatory in New Zealand.  Total 5 images were obtained with a wide- 
band Red filter (center wavelength ~ 750nm and FWHM ~ 250nm) and  we  
could identify the faint afterglow within the error circle (<0.5").
The identified R.A. Dec. are 19:09:11.752 -27:40:39.99 with an  
uncertainty of 0.14" (radius, 1sigma) and following are the  
photometric results: I magnitude = 20.24 +/- 0.32 at the mid-exposure  
time of 2008-04-13 12:29:16.4 UTC, 20.09 +/- 0.19 at 12:51:10.7 UTC,  
21.40 +/- 0.61 at 13:03:0.1 UTC, 20.05 +/- 0.17 at 13:42:47.0 UTC,  
and 20.75 +/- 0.25 at 14:13:06.6 UTC. These photometry were done by  
using the IRAF and calibrated against the USNO-B1.0 catalog stars,  
and not corrected for the Galactic extinction.

[GCN OPS NOTE(18apr08): By the moderator's choice, the "GCN 7594, Stamatikos et al"
wash changed to "GCN 7594, Beardmore et al". Ack to F. Marshall.]


GRB_name: GRB080413B
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7623
SUBJECT: GRB 080413B: Suzaku WAM observation of the prompt emission
DATE:    08/04/16 15:33:02 GMT
FROM:    Kazutaka Yamaoka at Aoyama Gakuin U  <yamaoka@phys.aoyama.ac.jp>

T. Enoto (Univ. of Tokyo), Y.E. Nakagawa, T. Tamagawa (RIKEN), 
T. Uehara, T. Takahashi, Y. Fukazawa, C. Kira, Y. Hanabata (Hiroshima
U.), K. Yamaoka, S. Sugita (Aoyama Gakuin U.), M. Tashiro, Y. Terada, 
Y. Urata, A. Endo, K. Onda, N. Kodaka, K. Morigami (Saitama U.), 
K. Nakazawa, K. Makishima (Univ. of Tokyo), E. Sonoda, M. Yamauchi, 
H. Tanaka, R. Hara (Univ. of Miyazaki), M. Ohno, M. Kokubun,
M. Suzuki, T. Takahashi (ISAS/JAXA), S. Hong (Nihon U.), 
on behalf of the Suzaku WAM team, report:

The Swift GRB 080413B (Swift/BAT trigger #309111 ; Stamatikos et al., GCN 7598) 
was detected by the Suzaku Wide-band All-sky Monitor (WAM) which
covers an energy range of 50 keV - 5 MeV at 8:51:11.645 UT (=T0).
The observed light curve shows a single peak starting at T0-0s, 
with a duration (T90) of about 2 seconds. The fluence in 150 - 1000 keV 
was (1.4 +/- 0.3) x 10^-6 erg/cm^2. The 1-s peak flux measured from T0+1s was 
3.4 +/- 0.2 photons/cm^2/s in the same energy range.

Preliminary result shows that the time-averaged spectrum from T0-1s to T0+8s 
is fitted by a single power-law with a photon index of 3.02 (+0.36, -0.32) 
(chi^2/d.o.f = 16.7/16) in 150 - 1000 keV. All the quoted errors are at statistical 
90% confidence level, in which the systematic uncertainties are not included.

The light curves with 1-sec time resolution for this burst are now available at:
http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/untrig/grb_table.html


GRB_name: GRB080413A
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7624
SUBJECT: GRB 080413A: Suzaku WAM observation of the prompt emission
DATE:    08/04/16 16:11:23 GMT
FROM:    Kazutaka Yamaoka at Aoyama Gakuin U  <yamaoka@phys.aoyama.ac.jp>

T. Enoto (Univ. of Tokyo), Y.E. Nakagawa, T. Tamagawa (RIKEN),
T. Uehara, T. Takahashi, Y. Fukazawa, C. Kira, Y. Hanabata
(Hiroshima U.), K. Yamaoka, S. Sugita (Aoyama Gakuin U.), M. Tashiro,
Y. Terada, Y. Urata, A. Endo, K. Onda, N. Kodaka, K. Morigami (Saitama U.),
K. Nakazawa, K. Makishima (Univ. of Tokyo), E. Sonoda, M. Yamauchi,
H. Tanaka, R. Hara (Univ. of Miyazaki), M. Ohno, M. Kokubun,
M. Suzuki, T. Takahashi (ISAS/JAXA), S. Hong (Nihon U.),
on behalf of the Suzaku WAM team, report:

The long GRB 080413A (Swift/BAT trigger #309096 ; Beardmore et al., GCN
 7594) was detected by the Suzaku Wide-band All-sky Monitor (WAM)
which covers an energy range of 50 keV - 5 MeV at 02:54:18.648 UT (=T0).
The observed light curve shows a clear double-peaked structure
 at T0+2s and T0+16s, and possible weak peak at T0+45s,
 with a total duration (T90) of about 19 seconds.
The fluence in 150 - 1000 keV was (2.2 +/- 0.5) x 10^-6 erg/cm^2.
The 1-s peak flux measured from T0+2s was 0.77 +/- 0.19 photons/cm^2/s
in the same energy range.

Preliminary result shows that the time-averaged spectrum from T0+0s to T0+20s
is fitted by a single power-law with a photon index of
2.4 +/- 0.4 (chi^2/d.o.f = 15.1/10) in 150 - 1000 keV.
All the quoted errors are at statistical 90% confidence level,
in which the systematic uncertainties are not included.

The light curves with 1-sec time resolution for this burst are now available at:
http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/untrig/grb_table.html


GRB_name: GRB080413A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7625
SUBJECT: GRB 080413A: Liverpool Telescope and Faulkes Telescope South optical observations
DATE:    08/04/16 17:23:09 GMT
FROM:    Andreja Gomboc at LT,ARI,Liverpool JMU  <ag@astro.livjm.ac.uk>

A. Gomboc (Ljubljana), C. Guidorzi (U. Bicocca/INAF-OAB), A. Melandri, I.A.
Steele, C.G. Mundell, D.F. Bersier, M.F. Bode, M.J. Burgdorf, S.N. Fraser,
S. Kobayashi, C.J. Mottram, R.J. Smith (Liverpool JMU), P. O'Brien, N.
Bannister, N. Tanvir (U. Leicester) report on behalf of larger GRB 
collaboration:

The Liverpool Telescope observed the field of GRB 080413A (trigger=309096,
Beardmore et al. GCN 7594) under poor weather conditions starting 2-hr after
the trigger. Observations continued with the Faulkes Telescope South.

In our coadded frames we do not detect any source at the position of the
optical afterglow (Beardmore et al. GCN 7594, Rykoff & Rujopakarn GCN 
7593) down to the limiting magnitudes reported below.


Telescope     Filter  Tstart(hr)  Tstop(hr)    Exposure(s)    M_lim
----------------------------------------------------------------------
Liverpool        R      2.0          2.5          760         15.7
Faulkes South    R     12.2         12.2           30         19.2
                  I     12.2         13.1         2080         21.7
----------------------------------------------------------------------

Magnitudes were calibrated with respect to USNOB1 R2 and I.


GRB_name: GRB080413B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7626
SUBJECT: GRB 080413B: Faulkes Telescope South optical afterglow observations
DATE:    08/04/16 17:48:34 GMT
FROM:    Andreja Gomboc at LT,ARI,Liverpool JMU  <ag@astro.livjm.ac.uk>

A. Gomboc (Ljubljana), C. Guidorzi (U. Bicocca/INAF-OAB), A. Melandri, 
I.A. Steele, C.G. Mundell, D.F. Bersier, M.F. Bode, M.J. Burgdorf, S.N. Fraser,
S. Kobayashi, C.J. Mottram, R.J. Smith (Liverpool JMU), P. O'Brien, N.
Bannister, N. Tanvir (U. Leicester) report on behalf of larger GRB 
collaboration:

The 2-m Faulkes Telescope South observed the field of GRB 080413B
(trigger=309111, Stamatikos et al. GCN 7598) starting 8.7-hr after the 
trigger time.
We detect the optical afterglow (Stamatikos et al. GCN 7598, Kruehler et al.
GCN 7599, Antonelli et al. GCN 7600) and measure the following magnitudes:

Filter   T_mid(hr)    Exposure(s)       Mag
----------------------------------------------------------------------
R          8.74          30          19.00 +/- 0.15
I          8.90         640          18.91 +/- 0.05
I          9.20        1080          19.15 +/- 0.05
I          9.54        1080          19.22 +/- 0.06
----------------------------------------------------------------------

Magnitudes were calibrated with respect to USNOB1 R2 and I.


GRB_name: GRB080319B
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7627
SUBJECT: GRB 080319B: Jet Break, Energetics, Supernova
DATE:    08/04/16 18:58:13 GMT
FROM:    Alexander Kann at TLS Tautenburg  <kann@tls-tautenburg.de>

D. A. Kann, S. Schulze (TLS Tautenburg) & A. C. Updike (Clemson 
University) report:

In light of recent reports on the further evolution of GRB 080319B, we did 
a preliminary analysis of the multiwavelength data set.

Jet Break:
Racusin et al. (GCN 7567) reported the existence of a potential jet break 
at 1.04 +/- 0.43 Ms in the X-ray band, with a hint of a steeper decay seen 
in the optical as well. Using the most up-to-date data from  the Swift XRT 
light curve repository (Evans et al. 2007), we confirm the  findings of 
the Swift team and derive (using data starting at 0.5 days after the GRB):

chi^2/d.o.f. = 39/58
alpha_1 = 1.01 +/- 0.05
alpha_2 = 2.40 +/- 0.39
t_b = 9.43 +/- 1.73 days (0.815 +/- 0.149 Ms)
n = 5 fixed, no "host galaxy"

These values are in agreement with those of the Swift team, with 
significantly reduced errors. We note that there seems to be a steep decay 
in the X-ray light curve from 0.35 to 0.5 days, and a similar evolution 
has been reported in the optical (Krugly et al., GCN 7519) at about the 
same time. This is reminiscent of the X-ray light curve of GRB 070110 
(Troja et al. 2007).

In the optical, we add data from Perley et al. (GCN 7535) and Tanvir et 
al. (GCN 7621) to the data set from Bloom et al. 2008 (arXiv:0803.3215). 
Tanvir et al. report a significant reddening, which we confirm. 

At the moment, it is unclear how much the host galaxy and a potential 
supernova contribute in the g band, but a roughly achromatic steepening is 
seen in this band (Tanvir et al.) in comparison to the X-ray light curve.

Energetics:
Using the prompt emission data derived from Konus-Wind (Golenetskii et 
al., GCN 7482), we find in the bolometric band (1 - 10000 keV, host 
frame):

E_iso = 1.32 +/- 0.03 x 10^54 erg (log E_iso = 54.12)

In the sample of Kann et al. 2007 (arXiv:0712.2186), only two GRBs (000131 
and 990123) exceed this value.

Using the jet break time derived above, as well as the redshift z=0.937 
(Vreeswijk et al., GCN 7444), and assuming standard parameters 
(constant-density medium, circumburst density n = 10 cm^-3, efficiency eta 
= 0.2), we find:

theta_jet = 10.24 +/- 0.71 degrees
E_jet = 2.11 +/- 0.30 x 10^52 erg (log E_jet = 52.3)

This value is comparable to or higher than for GRB 050904 (Tagliaferri et 
al. 2005, Frail et al. 2006), GRB 050820A (Cenko et al. 2006) and GRB 
070125 (Updike et al. 2008, Chandra et al. 2008), implying that this is 
the fourth hyper-energetic GRB (cf. Chandra et al. 2008). We note that 
broadband modeling may refine the circumburst density; if it is 
significantly higher than 10 cm^-3, the colimation-corrected energy 
will also be significantly higher.

Supernova:
In the i' band, the afterglow does not show a late steep decay, indicating 
the possibility of a supernova that is by now contributing to the optical 
transient (Tanvir et al.). Using the composite light curve (Bloom et al.) 
shifted to the i' band (using the early Rc - i' color), and assuming an 
achromatic break (t_b, alpha_2 fixed from the X-ray fit) and no host 
galaxy, we find, using data after 0.7 days (after the steep decay + 
plateau phase, Krugly et al.):

chi^2/d.o.f. = 44/10 (scatter)
alpha_1 = 1.33 +/- 0.02
k = 2.40 +/- 0.15
s = 1 fixed (stretch factor)

k is the peak luminosity in units of the SN 1998bw peak luminosity. This 
is a high value (Ferrero et al. 2006) and represents an upper limit on the 
SN flux. Assuming m_host(i') = 25, we find k = 1.24 +/- 0.14, a more 
reasonable result, indicating the contribution of a host galaxy to 
the late afterglow.

This message may be cited.


GRB_name: GRB080414A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7628
SUBJECT: Swift XRT and UVOT observations of GRB080414
DATE:    08/04/17 13:01:50 GMT
FROM:    Massimiliano de Pasquale at MSSL-UCL  <mdp@mssl.ucl.ac.uk>

   M. De Pasquale (MSSL/UCL), A.P. Beardmore (U. Leicester) and M.
Stamatikos (GSFC) report on the behalf of the Swift team:

  At 2008-04-15 14:15UT Swift performed a TOO observation of the INTEGRAL
burst GRB 080414 (Mereghetti et al., GCN Circ. 7618), some 56.6ks after
the trigger.

   No X-ray source was found in or near the IBAS error circle in a 3.9ks
exposure Swift/XRT Photon Counting mode image (taken from T+56.6ks to
T+85.5ks after the trigger) down to a 3 sigma limiting 0.3-10keV count
rate of 3e-3 count/s. Assuming a power-law spectrum of photon index 2
absorbed by the Galactic column density of 1.16e22 cm^-2 in the direction
of the burst, this corresponds to an observed 0.3-10keV flux limit of
1.9e-13 erg cm^-2 s^-1.


   The Swift/UVOT also observed the field. We do not detect an UV/Optical
afterglow in the IBAS error circle in all UVOT filters down to the
following 5 sigma upper limits:

   Filter  T_start  T_stop  Exp.    Mag UL (5sig)
           (ks)     (ks)    (s)

   v       56.9     79.9    272     > 18.3
   b       56.7     79.5    272     > 19.4
   u       56.7     84.7    326     > 19.2
   uvw1    56.6     84.7   1001     > 19.9
   uvm2    57.0     80.1    564     > 19.4
   uvw2    56.8     79.8   1085     > 19.9

   These upper limits are not corrected for the very large Galactic
extinction in the line of sight to GRB 080414, corresponding to a
reddening of E(B-V)=6.95 mag (Schlegel et al., 1998, ApJS, 500, 525). We
note that this value is rather uncertain in this direction.
The photometry is based on the UVOT photometric system described in Poole
et al. (2008, MNRAS, 383, 627).

[GCN OPS NOTE(17apr08): Per author's request, the "T+56ks to T+85.5ks"
was changed to "T+56.6ks to T+85.5ks".]


GRB_name: GRB080413B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7629
SUBJECT: GRB 080413B: Rapid PROMPT Observations
DATE:    08/04/17 17:02:01 GMT
FROM:    Thomas Summers Brennan at UNC/GRB Group  <bre@email.unc.edu>

T. Brennan, D. Reichart, M. Nysewander, A. LaCluyze, K. Ivarsen, J. A. 
Crain, M. Schubel, A. Foster, J. Haislip, J. Styblova, and A. Trotter 
report:

Skynet observed the localization of GRB 080413B (Stamatikos et al., GCN 
7598) with four of the 16" PROMPT telescopes at CTIO beginning 27 
seconds after the trigger (10 seconds after notification) in UBVRz'

We detect the afterglow (Stamatikos et al., GCN 7598) in BVRz'.  At 42 
seconds after the burst we measure B ~ 15.7 mag (calibrated to 2 USNO B1 
stars), at 55 seconds we measure V ~ 15.4 mag (calibrated to 2 USNO B1 
stars), and at 87 seconds we measure R ~ 15.4 mag (calibrated to 2 NOMAD 
stars).


GRB_name: GRB080413A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7630
SUBJECT: GRB 080413A: Suzaku/WAM and Swift/BAT joint spectral analysis
DATE:    08/04/18 21:50:05 GMT
FROM:    Takanori Sakamoto at NASA/GSFC  <takanori.sakamoto-1@nasa.gov>

M. Ohno, M. Kokubun, M. Suzuki, T. Takahashi (ISAS/JAXA)
K. Yamaoka, S. Sugita (Aoyama Gakuin U.),
T. Enoto (Univ. of Tokyo), Y.E. Nakagawa, T. Tamagawa (RIKEN),
T. Uehara, T. Takahashi, Y. Fukazawa, C. Kira, Y. Hanabata
(Hiroshima U.), M. Tashiro,
Y. Terada, Y. Urata, A. Endo, K. Onda, N. Kodaka, K. Morigami (Saitama U.),
K. Nakazawa, K. Makishima (Univ. of Tokyo), E. Sonoda, M. Yamauchi,
H. Tanaka, R. Hara (Univ. of Miyazaki), , S. Hong (Nihon U.),
on behalf of the Suzaku WAM team, report:

J. Tueller (GSFC), S. D. Barthelmy (GSFC), W. Baumgartner (GSFC/UMBC),
A. P. Beardmore (U Leicester), J. Cummings (GSFC/UMBC), E. Fenimore (LANL),
N. Gehrels (GSFC), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD),
K. McLean (GSFC/UMD), D. Palmer (LANL), T. Sakamoto (GSFC/UMBC),
G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU), T. Ukwatta (GWU)
(i.e. the Swift-BAT team):

report:

We performed the Suzaku/WAM and Swift/BAT joint fit spectral
analysis of GRB 080413A (Swift/BAT trigger #309096; Beardmore et al., 
GCN 7594).  The time interval of the spectral data for each 
instrument is chosen from T0(WAM)-1 to T0(WAM)+22 sec where
T0(WAM) is the trigger time of WAM at  02:54:18.648 UTC.  
This time interval includes the initial two peaks, but not 
the relatively soft third peak around T0(WAM)+45 sec which 
is clearly visible in the BAT data (Tueller et al., GCN 7604).  
The energy ranges which we used in the joint spectral analysis
are 13-150 keV and 150-1000 keV for Swift/BAT and Suzaku/WAM
respectively.  The spectral data of two instruments are fit
with the spectral model multiplied by the constant factor to
take into account the systematic uncertainties in the response
matrices of each instrument.

The spectrum is well fit with a power-law with exponential cutoff
model (dN/dE ~ E^{alpha} * exp(-(2+alpha)*E/Epeak)).  The constant
factors of each instrument agree within 20%.  No systematic residual
from the best fit model is seen in the spectral data of each instrument.
The best fit spectral parameters are: alpha = -1.2 +- 0.1 and
Epeak = 170 (-40/+80) keV (chi2/dof = 75/73).  The energy fluence
in the 15-1000 keV band calculated by a power-law with exponential
cutoff model for this 23 sec interval is 4.8 (-1.2/+0.4) x 10^-6 erg/cm2
(assuming the constant factor of the BAT is fixed to 1).

Assuming z = 2.433 (Thoene et al., GCN 7602) and a standard 
cosmology model with H_0 = 71 km/s/Mpc, Omega_M = 0.27, 
Omega_\Lambda = 0.73, the isotropic energy release is 
E_iso ~8x10^52 erg in 1 keV to 10 MeV at the GRB rest frame.   

All the quoted errors are at the 90% confidence level.


GRB_name: GRB080310A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7631
SUBJECT: GRB080310, BVRcIc field calibration
DATE:    08/04/19 14:17:49 GMT
FROM:    Arne A. Henden at AAVSO  <arne@aavso.org>

A. Henden (AAVSO) reports:

While the field of GRB080310 has been observed by SDSS, we have also
obtained a four-night BVRcIc field calibration using the 35cm robotic
telescope at Sonoita Research Observatory.  The calibration file
has a limiting magnitude around V=17, with good standards brighter
than V=11 or so.  The file is available at
ftp://ftp.aavso.org/public/calib/grb/grb080310.dat

This calibration is based on numerous Landolt standards, and has
an external zeropoint error of about 0.02mag. Our system is available
for any other bright BVRI calibrations (4<V<19) for this field or any
other field; contact the author for such requests.

The AAVSO thanks the Curry Foundation for their continued support of the
AAVSO International High Energy Network, and to John Gross of SRO for
providing setup assistance for this field.


GRB_name: GRB080420A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7632
SUBJECT: GRB 080420?: Swift detection of a possible short burst
DATE:    08/04/20 04:37:41 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

L. Vetere (PSU), D. N. Burrows (PSU), M. M. Chester (PSU),
D. Grupe (PSU), J. A. Kennea (PSU), H. A. Krimm (CRESST/GSFC/USRA),
C. B. Markwardt (CRESST/GSFC/UMD), C. Pagani (PSU),
D. M. Palmer (LANL), J. L. Racusin (PSU), M. Stamatikos (NASA/ORAU)
and M. C. Stroh (PSU) report on behalf of the Swift Team:

At 04:12:47 UT, the Swift Burst Alert Telescope (BAT) triggered and
located possible GRB 080420 (trigger=309665).  Swift slewed immediately 
to the calculated location.  The BAT on-board calculated location is 
RA, Dec 152.639, +43.242 which is 
   RA(J2000) = 10h 10m 33s
   Dec(J2000) = +43d 14' 33"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a single spike
structure in a single 64 msec bin.  The peak count rate
was ~1300 counts/sec (15-350 keV), at ~0 sec after the trigger. 

Because of the low significance of the detection (6.6 sigma) we
cannot positively confirm that this is a real event until we
receive the downlinked data from Malindi around 10:00 UT. 

The XRT began observing the source at 04:13:42 UT, 54 s after the BAT trigger. 
The on-board detection algorithm did not centroid on a source due to 
insufficient counts so no prompt X-ray position is available at the moment. 
No source is seen in 300 seconds of promptly downloaded data; therefore 
any X-ray source is extremely faint.  No further data will be available until
about 10 UT. 

UVOT took a finding chart exposure of 100 seconds with the White 
(160-650 nm)  filter starting 57 seconds after the BAT trigger, and 
an exposure of 400 seconds with the V filter starting 163 seconds 
after the BAT trigger. No afterglow candidate has  been found in  the
initial data products. The 2.7'x2.7' sub-image covers 25% of  the  BAT
error circle. The typical 3-sigma upper limit has been about 18.5 
mag. The 8'x8' region for the list of sources generated on-board  
covers 100% of the BAT error circle. The list of sources is typically
 complete  to about 18 mag. No correction has been made for the 
expected extinction  corresponding to E(B-V) of 0.01. 

Burst Advocate for this burst is L. Vetere (vetere AT astro.psu.edu). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)

[GCN OPS NOTE(21apr08): Per author's request, the "~2000 counts/sec"
in the first paragraph was changed to "~1300 counts/sec".]


GRB_name: GRB080420A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7633
SUBJECT: GRB 080420A: ROTSE-III Optical Limits on a possible short burst
DATE:    08/04/20 04:50:49 GMT
FROM:    Brad Schaefer at LSU  <schaefer@grb.phys.lsu.edu>

B. E. Schaefer (Louisiana State), F. Yuan (U Mich), W. Rujopakarn 
(Steward), report on behalf of the ROTSE collaboration:

ROTSE-IIIb, located at McDonald Observatory, Texas, responded to GRB
080420 (Swift trigger 309665; Vetere, L. et al., GCN 7632) a possible
short burst, producing images beginning 8.1 s after the GCN notice time.
An automated response took the first image at 04:13:10.2 UT, 23.0 s after
the burst, under fair conditions.  These observations were affected by the
Full Moon 75 degrees away. We took 10 5-sec, and 60 20-sec exposures.
These unfiltered images are calibrated relative to USNO A2.0 (R). Imaging
is on going.

Comparison to the DSS (second epoch) reveals no new sources within the 
3-sigma Swift/BAT error circle; the field is not crowded. Individual 
images have limiting magnitudes ranging from 16.1-17.1; we set the 
following specific limits.

start UT       end UT      t_exp(s)   mlim   t_start-tGRB(s)  Coadd?
--------------------------------------------------------------------
04:13:10.2   04:13:15.2         5     16.1           23.0       N
04:13:10.2   04:14:17.3        67     18.1           23.0       Y
04:24:09.3   04:28:51.6       282     18.5          682.1       Y


GRB_name: GRB080420A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7634
SUBJECT: Swift-BAT trigger 309665 is not a GRB
DATE:    08/04/20 13:32:43 GMT
FROM:    Hans Krimm at NASA-GSFC  <hans.a.krimm@nasa.gov>

H.A. Krimm (CRESST/GSFC/USRA) and L. Vetere (PSU) report on behalf of 
the Swift Team:

The Swift-BAT trigger (trigger=309665) at 04:12:47 UT on 20 April 2008,
tentatively labelled GRB 080420 (GCN 7632, Vetere et al.),
is not due to a GRB or any other astrophysical source.  This trigger
is due to a cosmic ray shower event in the instrument.  All events
occurred in the same 100 microsec window.


GRB_name: GRB080319A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7635
SUBJECT: GRB080319A: MAGIC telescope GeV observation
DATE:    08/04/20 19:22:07 GMT
FROM:    Markus Garczarczyk at MPI/MAGIC  <garcz@mppmu.mpg.de>

Garczarczyk M., Gaug M., Antonelli A., Bastieri D., Covino S., 
Galante N., La Barbera A., Longo F. and Scapin V. for the MAGIC 
collaboration

The MAGIC Imaging Atmospheric Cherenkov Telescope performed a follow-up 
observation of the BAT burst GRB080319A (GCN circular 7426, Pagani et 
al.). We received the GCN alert at 05:46:45 UT (T0+63s), data taking with 
MAGIC started at 05:50:32 UT (T0+290s). The observation continued for 
1736s, starting at the zenith angle of 35 degrees.

No evidence for VHE gamma-ray emission above the analysis threshold of
175 GeV was found. The observation was carried out in (less sensitive) 
moon-observation mode.

A preliminary analysis, for the hypothesis of steady emission and 
assumption of a differential photon spectral index of -2.5, yields the 
following 95% CL differential flux upper limits, including a 30% 
systematic uncertainty on the telescope efficiency:

E (125- 175 GeV): 0.57 * 10^-10 erg/cm^2/s
E (175- 300 GeV): 0.11 * 10^-10 erg/cm^2/s
E (300-1000 GeV): 0.06 * 10^-10 erg/cm^2/s

for a time window from 05:50:01 UT to 06:19:01 UT.

For the same time window, we can also exclude emission of a constant flux 
in any 100s time bin smaller than:

E (125- 175 GeV): 13.97 * 10^-10 erg/cm^2/s
E (175- 300 GeV):  4.34 * 10^-10 erg/cm^2/s
E (300-1000 GeV):  1.46 * 10^-10 erg/cm^2/s

This message can be cited.


GRB_name: GRB080319A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7636
SUBJECT: GRB 080319A : Liverpool and Faulkes Telescopes Observations
DATE:    08/04/21 17:34:09 GMT
FROM:    Andrea Melandri at Liverpool John Moores U  <axm@astro.livjm.ac.uk>

A. Melandri (Liverpool JMU), A. Gomboc (Ljubljana), C. Guidorzi
(INAF-OAB), R.J. Smith, I.A. Steele, C.G. Mundell, D.F. Bersier,
M.F. Bode, M.J. Burgdorf, S. Kobayashi, C.J. Mottram (Liverpool JMU),
P. O'Brien, N. Bannister, N. Tanvir (U. Leicester) report on behalf of 
larger GRB collaboration:


We observed the field of GRB 080319A (trigger = 306754, Pagani et al.
GCN 7426) with the Liverpool Telescope (T_start = 32 min after the burst
event) and the Faulkes Telescope North (T_start = 525 min after the burst
event).

The optical counterpart reported by Cenko et al. (GCN 7429) and Malesani
et al. (GCN 7436), is clearly visible inside the XRT error circle
(Beardmore et al., GCN 7448) in our first images :


Telescope   Filter   DT_mean(min)   Exposure(s)    Mag     Err
----------------------------------------------------------------------
   LT          r'        34.2         360         21.45   0.16
   LT          r'        43.3         600         21.94   0.40
   FTN         r'       542.3        1000        >20.61
----------------------------------------------------------------------


Magnitudes were calibrated with respect to SDSS calibration's field (Cool
et al. GCN 7467).


GRB_name: GRB080320A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7637
SUBJECT: GRB 080320 : Faulkes Telescope North Observations
DATE:    08/04/21 17:35:53 GMT
FROM:    Andrea Melandri at Liverpool John Moores U  <axm@astro.livjm.ac.uk>

A. Melandri (Liverpool JMU), A. Gomboc (Ljubljana), C. Guidorzi
(INAF-OAB), R.J. Smith, I.A. Steele, C.G. Mundell, D.F. Bersier, M.F. 
Bode, M.J. Burgdorf, S. Kobayashi, C.J. Mottram (Liverpool JMU),
P. O'Brien, N. Bannister, N. Tanvir (U. Leicester) report on behalf of 
larger GRB collaboration :


On 2008 March 20 (06:00:59UT) we observed the field of GRB 080320
(trigger=306858, Grupe et al. GCN 7473) with the Faulkes Telescope
North. Observations constited of 10x300s exposures acquired using the
SDSS-i' filter.

In our coadded frame we do not detect any source inside the refined XRT
error box (Goad et al. GCN 7479) or at the position of the faint infrared
afterglow reported by Tanvir et al. (GCN 7488) and Updike et al. (GCN
7491), down to the limiting magnitude reported below.


Telescope        Filter  DT_mean[min]  Exposure(s)    M_lim (3-sigma)

----------------------------------------------------------------------
Faulkes North      i'       108.4         3000         20.4
----------------------------------------------------------------------


GRB_name: GRB080315A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7638
SUBJECT: Possible GRB 080315: XRT non-detection of afterglow
DATE:    08/04/22 13:28:33 GMT
FROM:    Kim Page at U.of Leicester  <kpa@star.le.ac.uk>

K.L. Page (U. Leicester) and N. Gehrels (NASA/GSFC) report on behalf of 
the Swift-XRT team:

Swift-XRT performed follow-up observations of the possible GRB 080315 (BAT 
trigger number 306323) about a month after the trigger, in order to 
determine whether or not the possible X-ray afterglow mentioned in GCN 
Circ. 7420 had faded. We find that this source is at a count rate 
consistent with that of our original observation, so conclude that it is 
not the afterglow. Thus, no afterglow was detected for this trigger.

Excluding this constant X-ray source, the 3-sigma upper limit within the 
BAT error circle from the observation directly following the trigger (25 
ks on 2008-03-15) was 5.9 x 10^-4 count s^-1; the late-time data (30 ks 
between 2008-04-16 and 2008-04-21) provide a limit of 5.2 x 10^-4 count 
s^-1. 

We cannot rule out that this was a real burst, but given the lack of XRT 
detection and marginal BAT detection it is not likely.


GRB_name: GRB080426A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7639
SUBJECT: GRB 080426: Swift detection of a possibly short burst
DATE:    08/04/26 13:49:12 GMT
FROM:    David Burrows at PSU/Swift  <dxb15@psu.edu>

H. Ziaeepour (UCL-MSSL), S. D. Barthelmy (GSFC),
W. H. Baumgartner (GSFC/UMBC), A. P. Beardmore (U Leicester),
D. N. Burrows (PSU), N. Gehrels (NASA/GSFC), C. Guidorzi (INAF-OAB),
S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU),
N. P. M. Kuin (MSSL), J. Mao (INAF-OAB),
C. B. Markwardt (CRESST/GSFC/UMD), F. E. Marshall (NASA/GSFC),
P. T. O'Brien (U Leicester), S. R. Oates (UCL-MSSL), C. Pagani (PSU),
D. M. Palmer (LANL), D. Perez (U Leicester),
R. L. C. Starling (U Leicester), G. Tagliaferri (INAF-OAB),
T. N. Ukwatta (GSFC/GWU) and P. A. Ward (MSSL-UCL) report on behalf
of the Swift Team:

At 13:23:22 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 080426 (trigger=310219).  Swift slewed to the burst
after a brief delay due to Earth limb constraint. 
The BAT on-board calculated location is 
RA, Dec 26.574, +69.492 which is 
   RA(J2000) = 01h 46m 18s
   Dec(J2000) = +69d 29' 30"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a single-peaked
structure with a duration of about 2 sec.  The peak count rate
was ~7500 counts/sec (15-350 keV), at ~0 sec after the trigger. 

The XRT began observing the field at 13:27:05.2 UT, 222.5 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued
X-ray source with an enhanced position: RA, Dec 26.49931, 69.46856
which is equivalent to:
   RA(J2000)  = 01h 45m 59.83s
   Dec(J2000) = +69d 28' 06.8"
with an uncertainty of 2.8 arcseconds (radius, 90% containment). This
location is 126 arcseconds from the BAT onboard position, within the
BAT error circle. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of
3.65e+21 cm^-2 (Kalberla et al. 2005), so we cannot constrain the
redshift at this time using the relation from Grupe et al. (2007). A
summary of the promptly downlinked data is given at
http://www.swift.ac.uk/sper/310219/. 

UVOT took a finding chart exposure of 100 seconds with the White  
(160-650 nm)filter starting 226 seconds after the BAT trigger. No  
afterglow candidate has  been found in the initial data products. The 
typical 3-sigma upper limit has been about 18.5 mag. The 8'x8' 
region  for the list of sources generated on-board covers 100% of 
the XRT error circle. The list of sources is typically complete to 
about 18mag. No correction has been made for the expected 
extinction corresponding to E(B-V) of 0.79. 

Burst Advocate for this burst is H. Ziaeepour (hz AT mssl.ucl.ac.uk). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB080426A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7640
SUBJECT: GRB 080426, Swift-BAT refined analysis
DATE:    08/04/26 18:37:17 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

J. Cummings (GSFC/UMBC), S. D. Barthelmy (GSFC), W. Baumgartner (GSFC/UMBC),
E. Fenimore (LANL), N. Gehrels (GSFC), H. Krimm (GSFC/USRA),
C. Markwardt (GSFC/UMD), K. McLean (GSFC/UMD), D. Palmer (LANL),
T. Sakamoto (GSFC/UMBC), G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU),
J. Tueller (GSFC), T. Ukwatta (GWU), H. Ziaeepour (UCL-MSSL)
(i.e. the Swift-BAT team):
 
Using the data set from T-119 to T+183 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 080426 (trigger #310219)
(Ziaeepour, et al., GCN Circ. 7639).  The BAT ground-calculated position is
RA, Dec = 26.510, 69.469 deg which is 
   RA(J2000)  =  01h 46m 02.4s 
   Dec(J2000) = +69d 28' 07.9" 
with an uncertainty of 1.1 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 43%.
 
The mask-weighted light curve shows a single spike starting at T+0 and
ending at T+2.0 sec.  The lag analysis yields:
  Lag31 = 88 +/- 9 ms  (50-100 to 15-25 keV bands)
  Lag21 = 74 +/- 6 ms  (25-50  to 15-25 keV bands)
T90 (15-350 keV) is 1.7 +- 0.4 sec (estimated error including systematics).
While the T90 value puts this burst in the middle of the long and Short burst
T90-distribution peaks, the lag value puts this burst in the Long burst class.
 
The time-averaged spectrum from T+0.1 to T+2.3 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.98 +- 0.13.  The fluence in the 15-150 keV band is 3.7 +- 0.3 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T-0.08 sec in the 15-150 keV band
is 4.8 +- 0.3 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 

We note that this is an unusual burst.  The T90 for the 50-300 keV  
BATSE range is 1.3 sec which would put it in the short class in that  
era.  However, the long lag and a spectrum that is not hard lead us  
to believe it is in the long class.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/310219/BA/


GRB_name: GRB080426A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7641
SUBJECT: GRB 080426: Enhanced Swift-XRT position
DATE:    08/04/26 18:42:21 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 894 s of overlapping XRT Photon Counting mode and UVOT
data for GRB 080426, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 26.49890, +69.46823 which is equivalent
to:

RA (J2000): 01h 45m 59.74s
Dec (J2000): +69d 28' 05.6"

with an uncertainty of 1.8 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest position
can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is
described by Goad et al. (2007, A&A, 476, 1401
http://www.swift.ac.uk/xrt_positions/Goad.pdf), the current algorithm is an
extension of this method.

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB080426A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7642
SUBJECT: GRB080426: Swift/UVOT upper limits
DATE:    08/04/26 20:37:54 GMT
FROM:    Samantha Oates at MSSL  <sro@mssl.ucl.ac.uk>

S.R. Oates (UCL-MSSL) and H. Ziaeepour (UCL-MSSL) report on behalf of
the Swift/UVOT team.

The Swift/UVOT began settled observations the field of GRB 080426
(trigger 310219) 226 seconds after the BAT trigger (Ziaeepour, et al.,
GCN Circ. 7639). No afterglow is detected at the enhanced XRT position
(Beardmore, et al., GCN Circ. 7641) in any of the UVOT filters. The 3 
sigma upper limits are given below:

Filter   T_start  T_stop    Exp.    Mag UL (3sig)
            (s)    (s)
------------------------------------------------
white      226     326       98        >20.38
white      446     7457     362        >20.86
v          333     7868    1316        >19.98
b          431     7253     303        >20.01
u          407     7047     333        >19.79
uvw1       382     6843     352        >19.99
uvm2       357     7969     407        >19.94
uvw2       462     7663     510        >20.26
-------------------------------------------------

These upper limits are not corrected for the Galactic extinction in
the line of sight, corresponding to a reddening of E(B-V)= 0.798 mag
(Schlegel et al., 1998, ApJS, 500, 525). The photometry is based on
the UVOT photometric system described in Poole et al. (2008, MNRAS, 383, 
627).


GRB_name: GRB080426A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7643
SUBJECT: GRB 080426: Swift-XRT refined analysis
DATE:    08/04/26 22:03:22 GMT
FROM:    Andy Beardmore at U Leicester  <apb@star.le.ac.uk>

A.P. Beardmore (U. Leicester) and H. Ziaeepour (UCL-MSSL) report on behalf
of the Swift-XRT team :

The Swift-XRT began observing GRB 080426 (trigger=310219, Ziaeepour et
al.  GCN Circ. 7639) in Photon Counting mode, 230 s after the BAT
trigger.  The best XRT position for this burst is the UVOT-enhanced
position reported by Beardmore et al. (GCN Circ. 7641).

Three orbits of data out to T+13 ks, totalling 5.7 ks of exposure,
reveal a light curve which follows a simple power-law decay, with an
index of -1.07 +/- 0.08.

The spectrum from the first three orbits is well fit by an absorbed
power-law model, with a photon index of 2.01 +/- 0.25 and column density
of (5.3 +/- 1.3)e21 cm^-2, which is slightly in excess of the average
Galactic column density in this direction of 3.7e21 cm^-2. The
observed (unabsorbed) 0.3-10 keV flux is 5.1e-12 (9.1e-12)
erg cm^-2 s^-1.

If the burst continues to decay at the same rate, we predict an
XRT count rate of 2.0e-3 count/s at T+24 hours, which corresponds
to an observed 0.3-10 keV flux of approximately 1.2e-13 erg cm^-2 s^-1.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB080426A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7644
SUBJECT: GRB080426: Observations from CAHA
DATE:    08/04/26 23:18:44 GMT
FROM:    Antonio Deugarte at IAA-CSIC  <deugarte@iaa.es>

A. de Ugarte Postigo (ESO), D. A. Kann (TLS Tautenburg),
A.J. Castro-Tirado (IAA-CSIC, Granada), A. Aguirre (CAHA),
C. Jordi (U. Barcelona) report on behalf of a larger collaboration:

We have observed the XRT error circle (Beardmore et al. GCN 7641)
of the possible intermediate GRB 080426 (H. Ziaeepour et al.
GCN 7639, J. Cummings et al. GNC 7640) with the 2.2m telescope
at Calar Alto Observatory (Almera, Spain) at high airmass but
good conditions.

The observations started at 26 April 19:53:33 UT and were carried
out in B, V, R and I bands. In an I-band combined frame comprised
of 11x300s with mean epoch 7.50 hours after the burst, we do not
detect any source within the XRT error box down to a limiting
magnitude of I~22.5.

Further analysis is ongoing. This message may be cited.


GRB_name: GRB080430A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7646
SUBJECT: GRB 080430: TAROT Calern observatory optical observations
DATE:    08/04/30 20:09:33 GMT
FROM:    Alain Klotz at CESR-CNRS  <Alain.Klotz@free.fr>

Klotz, A. (CESR-OMP), Boer M. (OHP), Atteia J.L. (LATT-OMP) report:

We imaged the field of GRB 080430 detected by SWIFT
(trigger 310613) with the TAROT robotic telescope (D=25cm)
located at the Calern observatory, France.

The observations started 18.8s after the GRB trigger
(7.2s after the notice). The elevation of the field increased from
from 82 degrees above horizon and weather conditions
were good.

We detect a new fading source in the error box given by SWIFT
at the following position (+/- 3 arcsec):

RA(J2000) = 11h 01m 14.2s
DEC(J2000) +51d 41' 08"

OT was R~16 at 18.8s after GRB.

Magnitudes were estimated with the nearby USNO-B1 stars
and are not corrected for galactic dust extinction.

N.B. Galactic coordinates are lon=155.5591 lat=+57.8882
and the galactic extinction in R band is 0.0 magnitudes
estimated from D. Schlegel et al. 1998ApJ...500..525S.

This message may be cited.

5141'08"


GRB_name: GRB080430A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7647
SUBJECT: GRB 080430: Swift detection of a burst with optical afterglow
DATE:    08/04/30 20:16:10 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

C. Guidorzi (INAF-OAB), S. D. Barthelmy (GSFC),
A. P. Beardmore (U Leicester), D. N. Burrows (PSU),
J. R. Cummings (NASA/UMBC), N. Gehrels (NASA/GSFC),
O. Godet (U Leicester), S. T. Holland (CRESST/USRA/GSFC),
J. A. Kennea (PSU), H. A. Krimm (CRESST/GSFC/USRA),
W.L Landsman (GSFC), C. B. Markwardt (CRESST/GSFC/UMD),
K. M. McLean (GSFC/UMD), P. T. O'Brien (U Leicester),
D. M. Palmer (LANL), D. Perez (U Leicester), P. Romano (INAF-IASFPA),
T. Sakamoto (NASA/UMBC), M. Stamatikos (NASA/ORAU),
R. L. C. Starling (U Leicester), G. Tagliaferri (INAF-OAB),
T. N. Ukwatta (GSFC/GWU), D. E. Vanden Berk (PSU) and
H. Ziaeepour (UCL-MSSL) report on behalf of the Swift Team:

At 19:53:02 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 080430 (trigger=310613).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 165.322, +51.689 which is 
   RA(J2000) = 11h 01m 17s
   Dec(J2000) = +51d 41' 22"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a single FRED peak
structure with a duration of about 20 sec.  The peak count rate
was ~6000 counts/sec (15-350 keV), at ~1 sec after the trigger. 

The XRT began observing the field at 19:53:50.9 UT, 48.9 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
fading, uncatalogued X-ray source with an enhanced position: RA, Dec
165.31041, 51.68546 which is equivalent to:
   RA(J2000)  = 11h 01m 14.50s
   Dec(J2000) = +51d 41' 07.7"
with an uncertainty of 2.7 arcseconds (radius, 90% containment). This
location is 28 arcseconds from the BAT onboard position, within the BAT
error circle. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density in excess of the Galactic value (9.59e+19
cm^-2, Kalberla et al. 2005), with an excess column of 3 (+1.33/-1.17)
x 10^21 cm^-2 (90% confidence). The relation of Grupe et al. (2007)
implies that this burst has a redshift z<3.5, although high redshift
fits to the absorbed XRT spectrum are possible if paired with an
anomalously large column. A summary of the promptly downlinked data is
given at http://www.swift.ac.uk/sper/310613/. 

The initial flux in the 2.5 s image was 1.26e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 400 seconds with the v filter starting
164 seconds after the BAT trigger. There is a candidate afterglow in the
rapidly available 2.7'x2.7' sub-image at
  RA(J2000)  = 11:01:14.71 = 165.3113
  DEC(J2000) = +51:41:08.5  =  51.6857
with a 1-sigma error radius of about 0.5 arc sec. This position is 2.2 arc sec. 
from the center of the XRT error circle. The estimated magnitude is 17.6 with a
1-sigma error of about 0.5 mag. A white filter finding chart exposure was also
taken before the v filter, showing that the afterglow is fading.  No correction
has been made for the expected extinction of about 0.04 magnitudes. 

Burst Advocate for this burst is C. Guidorzi (cristiano.guidorzi AT brera.inaf.it). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB080430A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7648
SUBJECT: GRB 080430: Bootes observation
DATE:    08/04/30 20:21:25 GMT
FROM:    Martin Jelinek at Inst.Astrophys.Andalucia,Granada  <mates@iaa.es>

M. Jelinek, P. Kubanek, J. Gorosabel, A. J. Castro-Tirado, F.
Aceituno (IAA-CSIC Granada), L. Sabau-Graziati (INTA Madrid),
A. de Ugarte Postigo (ESO Santiago), R. Hudec (ASU-CAS
Ondrejov), P. Perez-Gonzalez and J.  Zamorano (UCM Madrid)
report on behalf of a larger collaboration:

The BOOTES-1 0.3m telescope in South Spain observed GRB
080413A, starting at 19:53:36 UT (34 sec after the GRB). A
sequence of preprogrammed 6 sec, 20 and 60 sec exposures was
obtained. We find an optical counterpart at the coordinates
(J2000)

11:01:14.777  +51:41:08.61

with an unfiltered magnitude ~17.0 at ~60s after the GRB.

We continue observing the object with the 1.5m telescope at
Observatorio Sierra Nevada, which confirms the reality of the
object.


-- 
Martin Jelinek, +420602105255, +34617840945, sirrah.cz/mates
       Instituto de Astrofisica de Andalucia, Granada

# vim:set ai et sts=8 tw=60:


GRB_name: GRB080430A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7649
SUBJECT: GRB 080430 - SDSS Pre-Burst Observations
DATE:    08/04/30 20:36:36 GMT
FROM:    Richard J. Cool at U.of AZ/Steward Obs  <rcool@as.arizona.edu>

Richard J. Cool (Arizona), Daniel J. Eisenstein (Arizona),
David W. Hogg (NYU), Michael R. Blanton (NYU), David J. Schlegel
(LBNL), J. Brinkmann (APO), Donald Q. Lamb (Chicago), Donald
P. Schneider (PSU), and Daniel E. Vanden Berk (PSU) report:

The Sloan Digital Sky Survey (SDSS) imaged the field of burst
GRB080430 prior to the burst.  As these data should be useful
as a pre-burst comparison and for calibrating photometry,
we are supplying the images and photometry measurements for
this GRB field to the community.

Data from the SDSS, including 5 FITS images, 3 JPGS, and
3 files of photometry and astrometry, are being placed at
http://mizar.as.arizona.edu/~grb/public/GRB080430

We supply FITS images in each of the 5 SDSS bands of a 8'x8'
region centered on the GRB position (ra=165.322 (11:01:17.3),
dec=51.6890 (51:41:20.4); Swift-BAT TRIGGER 310613), as well
as 3 gri color-composite JPGs (with different stretches). The
units in the FITS images are nanomaggies per pixel.  A pixel
is 0.396 arcsec on a side. A nanomaggie is a flux-density unit
equal to 10^-9 of a magnitude 0 source or, to the extent that
SDSS is an AB system, 3.631e-6 Jy.  The FITS images have WCS
astrometric information.

In the file GRB080430_sdss.calstar.dat, we report photometry
and astrometry of 193 bright stars (r<20.5) within 15' of the
burst location.  The magnitudes presented in this file are asinh
magnitudes as are standard in the SDSS (Lupton 1999, AJ, 118,
1406). Beware that some of these stars are not well-detected
in the u-band; use the errors and object flags to monitor
data quality.

In the files GRB080430_sdss.objects_flux.dat and
GRB080430_sdss.objects_magnitudes.dat, we report photometry
of 582 objects detected within 6' of the GRB position.
We have removed saturated objects and objects with model
magnitudes fainter than 23.0 in the r-band.  The fluxes listed
in GRB080430_sdss.objects_flux.dat are in nanomaggies while
the magnitudes listed in GRB080430_sdss.objects_magnitudes.dat
are asinh magnitudes.

All quantities reported are standard SDSS photometry, meaning
that they are very close to AB zeropoints and magnitudes are
quoted in asinh magnitudes.  Photometric zeropoints are known
to about 2% rms.  None of the photometry is corrected for
dust extinction.  The Schlegel, Finkbeiner, and Davis (1998)
predictions for this region are A_U=0.061 mag, A_g=0.045 mag,
A_r = 0.032 mag, A_i=0.025 mag, and A_z=0.017 mag.

There are currently no objects within 6 arcminutes of the GRB
position in the SDSS spectroscopic database.


SDSS astrometry is generally better than 0.1 arcsecond per
coordinate.  Users requiring high precision astrometry should
take note that the SDSS astrometric system can differ from
other systems such as those used in other notices; we have
not checked the offsets in this region.

More detailed information pertaining to our SDSS GRB releases
can be found in our initial data release paper (Cool et
al. 2006, PASP 118, 733).  See the SDSS DR4 documentation for
more details: http://www.sdss.org/dr5.

These data have been reduced using a slightly different
pipeline than that used for SDSS public data releases.
We cannot guarantee that the values here will exactly match
those in the data release in which these data are included.
In particular, we expect the photometric calibrations to differ
by of order 0.01 mag.

This note may be cited, but please also cite the SDSS data
release paper, Adelman-McCarthy et al. (2007, ApJS, 172, 634),
when using the data or referring to the technical documentation.


GRB_name: GRB080430A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7650
SUBJECT: GRB 080430: Spectroscopy from CAHA
DATE:    08/05/01 02:51:20 GMT
FROM:    Antonio Deugarte at IAA-CSIC  <deugarte@iaa.es>

A. de Ugarte Postigo, L. Christensen (ESO), J. Gorosabel (IAA-CSIC),
C. Thne (Dark), D.A. Kann (TLS), A. Mora (UAM), T. Szeifert (ESO),
M. Jelinek, A.J. Castro-Tirado (IAA-CSIC), S. Pedraz (CAHA),
N. Cardiel, D. Montes (UCM). On behalf of a larger collaboration report:

We have obtained spectroscopic observations of GRB 080430 from the 2.2m
Calar
Alto telescope (+CAFOS) starting at 21:11 UT (78 minutes after the
burst). The
observations consisted of 3x1200s integrations in low resolution. The
signal to noise
ratio is low but after a preliminary reduction we may conclude:

1) Continuum is clearly detected down to 3500 Angstroms, implying a
redshift smaller
than 1.9.
2) We detect an absorption feature at ~4900 Angstroms that we suggest to
be the
MgII doublet (2796.3, 2803.5), implying a most probable redshift of ~0.75.

Further analysis is ongoing. Additional spectroscopic observations are
encouraged.

This message may be cited.


GRB_name: GRB080430A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7651
SUBJECT: GRB080430: Optical observation in AsU CAS Ondrejov & Brno
DATE:    08/05/01 04:02:43 GMT
FROM:    Matus Kocka at Monteboo Obs,Masaryk U,Brno  <koci@astronom.sk>

M. Kocka, M. Nekola, J. Strobl, R. Hudec, C. Polasek (AsU CAS - Ondrejov),
M. Jelinek, P. Kubanek (IAA-CSIC - Granada),
R. Novak (N. Copernicus Observatory - Brno)
F. Munz (IASF/INAF - Bologna)

The 0.5m D50 telescope in AsU CAS Ondrejov, Czech Republic observed
GRB080430. Observation started at 20:57:02 UT. After 29 x 20 sec
exposures we detected optical counterpart at the coordinates:

(J2000) 11:01:14.7  +51:41:08.6  (M. Jelinek & al; GCN CIRCULAR 7648)

Calibrated to near USNO et ESO star in R magnitude ~ 18.9mag (21:02:23 
UT mid-time of exposure)  
http://physics.muni.cz/~koci/GRB080430/grb080430.jpg

The 0.4m N. Copernicus Observatory telescope at Brno Czech Republic also 
observed
same coordinates with the same results.
http://ccder.blogspot.com/

Further analysis is in progress

This message may be cited.


GRB_name: GRB080430A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7652
SUBJECT: GRB 080430: Enhanced Swift-XRT position
DATE:    08/05/01 04:40:50 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 18 s of overlapping XRT Photon Counting mode and UVOT
data for GRB 080430, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 165.31109, +51.68539 which is equivalent
to:

RA (J2000): 11h 01m 14.66s
Dec (J2000): +51d 41' 07.4"

with an uncertainty of 1.7 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest position
can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is
described by Goad et al. (2007, A&A, 476, 1401
http://www.swift.ac.uk/xrt_positions/Goad.pdf), the current algorithm is an
extension of this method.

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB080430A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7653
SUBJECT: GRB 080430: Swift-XRT refined analysis
DATE:    08/05/01 10:25:39 GMT
FROM:    Cristiano Guidorzi at INAF-OAB  <cristiano.guidorzi@brera.inaf.it>

C. Guidorzi, J. Mao (INAF-OAB), P. Evans and K.L. Page (Leicester)
report on behalf of the Swift-XRT team:

The Swift-XRT began observing GRB 080430 (trigger=310613, Guidorzi et
al., GCN Circ. 7647) in Window Timing mode, 55 s after the BAT
trigger. Using 2 ks of overlapping XRT and UVOT data, we can improve
the UVOT-enhanced XRT position given by Evans in al. (GCN Circ. 7652)
to RA, Dec = 165.31104, +51.68558 which is equivalent to:

RA (J2000): 11h 01m 14.65s
Dec (J2000): +51d 41' 08.1"

with an uncertainty of 1.4 arcsec (radius, 90% confidence).

The light curve of the first five orbits, from 55 s to 24.7 ks,
totalling 10.3 ks of exposure, can be modelled with a double broken
power law with the following best-fitting parameters:
alpha_1=2.34+/-0.16, t_break1=309 (-33,+58) s, alpha_2=0.38+/-0.06,
t_break2=10.3 (-2.2,+3.8) ks, alpha_3=0.65+/-0.17 (chisq/dof=77/81).

The WT mode spectrum spanning from 55 to 138 s can be fit by an absorbed
power-law model, with a photon index of 2.42 (-0.14, +0.27) and column
density of 4.6(-2.6, +3.2)e20 cm^-2, which is in excess of the average
Galactic column density in this direction of 9.6e19 cm^-2.
The PC mode spectrum of orbits 2 to 5, spanning from 5.6 to 24.7 ks,
is fit with a higher column density, (2.0+/-0.4)e21 cm^-2 and
a power-law index of 2.3+/-0.2.
The corresponding observed (unabsorbed) 0.3-10 keV flux is 5.0e-12
(8.5e-12) erg cm^-2 s^-1.

If the burst continues to decay at the same rate, we predict an
XRT count rate of 3.8e-2 count/s at T+24 hours, which corresponds
to an observed 0.3-10 keV flux of approximately 1.7e-12 erg cm^-2 s^-1.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB080430A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7654
SUBJECT: GRB 080430:  Hobby-Eberly Telescope Absorption Redshift 
DATE:    08/05/01 10:47:05 GMT
FROM:    Antonino Cucchiara at PSU  <cucchiara@astro.psu.edu>

A. Cucchiara and D. B. Fox (Penn State) report:

"Starting on 2008 May 1.21 UT we used the Marcario LRS spectrograph
on the Hobby-Eberly Telescope (R ~ 230) to obtain a 1200s spectrum
of the optical afterglow of GRB 080430 (Guidorzi et al., GCN 7647).
The spectrum covers the wavelength range 4100 to 10,500 Angstrom.  We
clearly observe metal absorption features corresponding to the MgII
doublet (2796, 2803 A) and MgI (2852 A) at redshift z = 0.767. The
spectrum does not show any other significant features, consistent
with Calar Alto telescope observations (de Ugarte Postigo et al.,
GCN 7650).

We thank the HET staff for performing this observation."


GRB_name: GRB080430A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7655
SUBJECT: GRB080430: optical observations
DATE:    08/05/01 12:01:37 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

M. Andreev, A. Sergeev (Terskol Branch of Institute of Astronomy), Ju.
Babina (CrAO), V. Petkov, A. Kurenya (BNO INR RAS), A. Pozanenko (IKI) on
behalf of larger GRB follow up collaboration  report:

We observed the afterglow (Klotz et al. GCN 7646, Guidorzi et al. GCN 7647,
Jelinek et al. GCN 7648) of GRB080430 (Guidorzi et al. GCN 7647) with
Zeiss-600 of  Mt.Terskol observatory on Apr.30.  The fading afterglow is
clearly detected in combined images. A photometry of the OT against
USNO-B1.0 stars is following:

UT,              Exposure,   R_mag
(mid time)

Apr.30.8906  15 x 60s  19.10  +/- 0.20
Apr.30.9014  15 x 60s  19.40  +/- 0.20
Apr.30.9130  15 x 60s  19.75  +/- 0.25

The message may be cited.


GRB_name: GRB080430A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7656
SUBJECT: GRB 080430, Swift-BAT refined analysis
DATE:    08/05/01 13:19:08 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

M. Stamatikos (GSFC/ORAU), S. D. Barthelmy (GSFC), W. Baumgartner (GSFC/UMBC),
J. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC),
C. Guidorzi (INAF-OAB), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD),
K. McLean (GSFC/UMD), D. Palmer (LANL), T. Sakamoto (GSFC/UMBC),
G. Sato (GSFC/ISAS), J. Tueller (GSFC), T. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-240 to T+962 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 080430 (trigger #310613)
(Guidorzi, et al., GCN Circ. 7647).  The BAT ground-calculated position is
RA, Dec = 165.331, 51.682 deg, which is 
   RA(J2000)  =  11h 01m 19.4s 
   Dec(J2000) = +51d 40' 55.5" 
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 100%.
 
The mask-weighted light curve shows a single FRED peak starting at ~T-0.7 sec,
peaking at ~T+1.5 sec, and ending at ~T+60 sec.  T90 (15-350 keV) is
16.2 +- 2.4 sec (estimated error including systematics).
 
The time-averaged spectrum from T-0.3 to T+21.3 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.73 +- 0.09.  The fluence in the 15-150 keV band is 1.2 +- 0.1 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+1.70 sec in the 15-150 keV band
is 2.6 +- 0.2 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/310613/BA/


GRB_name: GRB080430A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7657
SUBJECT: GRB 080430 optical observations
DATE:    08/05/01 16:35:47 GMT
FROM:    AAVSO GRB Network at AAVSO  <matthewt@aavso.org>

Arto Oksanen (Muurame, Finland) and Veli-Pekka Hentunen (Varkaus, Finland) 
report to the AAVSO High Energy Network the following optical observations 
of GRB 080430 (Guidorzi et al., GCN Circular #7647):

Arto Oksanen (Hankasalmi Obs., Hankasalmi, Finland) reports the detection 
of the optical counterpart of GRB 080430.  Unfiltered observations were 
made using a 0.4-meter RC telescope with an SBIG STL-1001E CCD.  The 
initial Swift XRT position was observed unfiltered with an initial set of 
10 60-second exposures having a mid-point time of 2008 April 30, 20:08:54 
UT; the afterglow was detected with a magnitude of 18.1 +/- 0.05 
calibrated relative to GSC 3450-0639.  Astrometry of the initial frames 
yields a position of RA 11:01:14.76 , Dec +51:41:08.9 (USNOA2.0 ref, +/- 
0.4 arcseconds), which is within the stated uncertainties of the UVOT 
position (GCNCirc #7647).

Images taken between April 30.839 and April 30.969 UT were reanalyzed and 
calibrated relative to two USNO-B1.0 stars of magnitude ~16.5. Photometry 
of combined frames yields a smoothly decaying light curve during the span 
of observations:

    obs midpoint    CR error
2008 April 30.839 17.798 0.088
2008 April 30.849 18.329 0.120
2008 April 30.860 18.484 0.087
2008 April 30.875 18.751 0.076
2008 April 30.893 18.868 0.055
2008 April 30.911 18.956 0.052
2008 April 30.929 19.044 0.067
2008 April 30.949 19.012 0.064
2008 April 30.969 19.156 0.076

A detailed report of the initial observations is available at the following URL:
ftp://ftp.aavso.org/grb/A.Oksanen_GRB080430_2454587.38588_.txt

A FITS image of this observation is available at the following URL:
ftp://ftp.aavso.org/grb/A.Oksanen_GRB080430_2454587.38588_.fits


Markku Nissinen and Veli-Pekka Hentunen (Taurus Hill Observatory, Varkaus, 
Finland) also report the detection of the optical afterglow of GRB 080430. 
Observations were made using a Meade LX-200 0.3-meter telescope with an 
SBIG ST8-XME CCD; observations were made using both clear and R filters. 
A total of six 600-second exposures were obtained having an average 
midpoint time of 2008 April 30.943.  Photometry of the combined clear and 
Rc frames yields magnitudes of CR=19.2+/-0.3 and R=19.5+/-0.5 calibrated 
relative to the GSC2.3 star N7JI005540.  The observers noted the sky was 
not completely dark due to their high latitude and time of year.

The AAVSO thanks the Curry Foundation for their continued support of the 
AAVSO International High Energy Network.


GRB_name: GRB080430A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7658
SUBJECT: GRB 080430 - multicolor observations of the afterglow
DATE:    08/05/01 21:03:39 GMT
FROM:    Christina Thoene at Niels Bohr Institute,DARK Cosmo Ctr  <cthoene@astro.ku.dk>

Christina C. Thoene (DARK), Johan P. U. Fynbo (DARK), Antonio de Ugarte
Postigo (ESO), D. Alexander Kann (TLS), Nicolaas E. Groeneboom, ystein
Rudjord, Jostein R. Kristiansen (Univ. Oslo) and Tapio Purismo (NOT)
report:

We observed the afterglow (GCN 7646, Klotz et al.) of GRB 080430 (GCN
7647, Guidorzi et al.) with MOSCA at the NOT/La Palma on Apr. 30 starting
1.21h after the burst. Observations in UBVRI filters with exposure times
of 150s in each filter were acquired.
The afterglow is clearly detected in all bands and we derive the following
preliminary magnitudes based on the pre-burst SDSS calibrations (GCN 7649,
Cool et al.) and standard transformations between SDSS and Bessell
filters, times given are the start of the exposures.

t-t0(h)  band   mag
1.92     U         19.9 +- 0.2
1.74     B         19.8 +- 0.1
1.56     V         19.3 +- 0.1
1.21     R         19.0 +- 0.1
1.38     I           18.7 +- 0.1

The blue colors and the detection down to the U band are consistent with
the low redshift of that burst, z=0.767 as found by de Ugarte Postigo et
al. (GCN 7650) and Cucchiara et al. (GCN 7654).


GRB_name: GRB080430A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7659
SUBJECT: VLA radio upper limit on GRB 080430
DATE:    08/05/01 21:31:39 GMT
FROM:    Poonam Chandra at U Virginia/NRAO  <pc8s@virginia.edu>

Poonam Chandra (NRAO/UVA) and Dale A. Frail (NRAO) report on behalf
of the Caltech-NRAO-Carnegie GRB Collaboration:

"We used the Very Large Array to observe the field of view toward GRB
080430 (GCN 7647) at a frequency of 8.46 GHz at 2008 May 1.17 UT.
We do not detect the GRB afterglow at the UVOT afterglow position (GCN 7647).
The flux density at the  GRB afterglow position is 68  46 uJy.

The National Radio Astronomy Observatory is a facility of the National
Science Foundation operated under cooperative agreement by Associated
Universities, Inc."


GRB_name: GRB080430A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7660
SUBJECT: GRB080430: Swift/UVOT observations
DATE:    08/05/01 21:49:40 GMT
FROM:    Wayne Landsman at GSFC/SSAI  <wayne.b.landsman@nasa.gov>

W.B. Landsman (NASA/GSFC) and C. Guidorzi (INAF-OAB)  report on behalf 
of the Swift/UVOT team

The Swift/UVOT observed the field of GRB 080430 starting at 58s after  
the BAT trigger (Guidorzi et al., GCN 7647). We detect the afterglow in 
all seven UVOT filters at the position

RA(J2000)  =   11:01:14.66
DEC(J2000) =  +51:41:08.4

with an estimated uncertainty of 0.5 arcsec (radius, 90% confidence).  
This position is consistent with the enhanced XRT position (Guidorzi et 
al. GCN 7653)
and the position reported from  BOOTES obervations by Jelinek et al.  
(GCN 7648).     The detection in the UVW2 (1950 A) filter is consistent 
with the
redshift of ~0.76 determined from spectroscopic observations by Deugarte 
Postigo et al. (GCN 7650) and  Cucchiara & Fox (GCN 7654). The temporal 
slope in the white filter out to 30400 seconds is approximately alpha = 
0.23.

UVOT photometry from early individual images is reported below.     

Filter    Tmid(s)     Expo(s)            Magnitude
-----------------------------------------------------
White      108          98              17.08  0.03
White      928          98              18.23  0.05
v          364         393              17.64  0.06
v         1184         393              18.50  0.09
b         5989         197              20.05  0.21
u         5784         197              18.92  0.12
w1        7014         197              18.89  0.16
m2        6809         197              18.88  0.22
w2        5684         197              19.24  0.20
-----------------------------------------------------

These magnitudes are not corrected for the Galactic extinction  
corresponding to a reddening of E{B-V} = 0.012 mag (Schlegel et al. 
1998).  The photometry is on the UVOT flight system described in Poole 
et al. (2008,MNRAS,383,627).


GRB_name: GRB080430A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7661
SUBJECT: GRB080430: RTT150 Optical Observations
DATE:    08/05/02 00:18:18 GMT
FROM:    Irek Khamitov at TUG  <irekk@tug.tug.tubitak.gov.tr>

I. Khamitov (TUG), I. Bikmaev, R. Gumerov,
A. Nemtinov, N. Sakhibullin (KSU/AST),
R. Burenin, M. Pavlinsky, R. Sunyaev (IKI),
Z. Eker (TUG), U. Kiziloglu (METU), E. Gogus (Sabanci Uni.)

report:

The optical counterpart (GCN7646) of GRB 080430 (GCN 7647) was observed 
with Russian-Turkish 1.5-m telescope (RTT150, Bakirlitepe, TUBITAK 
National Observatory, Turkey), starting at May 01, 21:58 UT, i.e.
~26.08 hours after the burst, using Andor CCD.

A series of frames 3*300s in R and 3*600s in B bands were made.
The afterglow is clearly detected  in all images. Using USNO-B1 star
(416-022819, RA=11:01:16.86, DEC=+51:40:38.5, B2MAG=17.79, R2MAG=16.61)
we estimated the following magnitudes for the OT  on combined images:

t-t0 (h) band mag  err
26.25  R 21.3 0.1
27.98  B 22.3 0.1


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GRB_name: GRB080430A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7662
SUBJECT: GRB 080430: Shallow decay
DATE:    08/05/02 02:51:50 GMT
FROM:    Antonio Deugarte at IAA-CSIC  <deugarte@iaa.es>

A. de Ugarte Postigo (ESO), C.C. Thne (Dark), F. Aceituno (IAA-CSIC),
Nicolaas E. Groeneboom, ystein Rudjord, Jostein R. Kristiansen (Univ.
Oslo)
and Tapio Purismo (NOT) on behalf of a larger collaboration report:

We are continuing with the monitoring of the afterglow (Klotz et al. GCN
7646)
of GRB 080430 (Guidorzi et al., GCN 7647) with the 1.5m OSN telescope
(Sierra
Nevada Observatory) and the 2.5m NOT+MOSCA (Roque de los Muchachos
Observatory) in I band. During the first day of observations we observe a
steady
decay with a shallow slope of alpha ~ 0.6 (f ~ t^-alpha), being at a
magnitude of
I ~ 20.5 one day after the burst.

Further observations are encouraged. This message can be cited.


GRB_name: GRB080430A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7663
SUBJECT: GRB 080430: Optical observations
DATE:    08/05/02 08:33:59 GMT
FROM:    Shashi Bhushan Pandey at ARIES, INDIA  <shashi@aries.ernet.in>

S. B. Pandey, Rupak Roy and Brijesh Kumar (ARIES, NainiTal, India, on behal=
f of larger Indian GRB collaboration)
We observed Swift GRB 080430 with 1.04m telescope NainiTal starting ~20.0 h=
ours after the burst (Guidorzi et al. GCN 7647). Observations were performe=
d in R_c and I_c filters.
Photometry of one of the R_c frame (exposure time 1800s) shows theafterglow=
 around ~ 20.5 mag as reported in GCN 7646 and GCN 7648. The reported magni=
tude is determined in comparison to nearby USNO stars.
This message may be cited.


GRB_name: GRB080411A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7664
SUBJECT: GRB 080411: Continued Swift Monitoring
DATE:    08/05/02 21:04:17 GMT
FROM:    Frank Marshall at GSFC  <marshall@milkyway.gsfc.nasa.gov>

F.E. Marshall (NASA/GSFC), O. Godet (U. Leicester) and S.R. Oates (MSSL-UCL)
report on behalf of the Swift team:

The XRT and UVOT instruments on Swift continue to detect GRB 080411 
19 days after the BAT trigger (Marshall et al., GCN Circ. 7584). 
The X-ray light curve shows a broken power-law behaviour with 
breaks at about T+8 ks and T+240 ks and additional short-term features
at late times. Since the latter break,
the decay index has been 1.54 +/- 0.12, and the 0.6-10 keV flux
at T+1600 ks was 1.3 x 10^-13 ergs/s/cm^2.
The optical light curve also shows a similar broken power-law behaviour.
At T+1600 ks the magnitude (uncorrected for Galactic extinction)
in the broad-band white filter was 22.7 +/- 0.2 using the UVOT 
photometric system (Poole et al. MNRAS 383, 627 (2008)). Recently the 
decay index has been 1.30 +/- 0.03.

Additional Swift observations of GRB 080411 are planned.
Since the optical afterglow is approaching the sensitivity
limit for UVOT, ground-based observations are encouraged.

Please contact the Swift Burst Advocate for this burst
at marshall AT milkyway.gsfc.nasa.gov if you desire
additional information regarding the Swift followup
of this burst.


GRB_name: GRB080503A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7665
SUBJECT: GRB 080503: Swift detection of a short burst
DATE:    08/05/03 12:50:13 GMT
FROM:    David Burrows at PSU/Swift  <dxb15@psu.edu>

J. Mao (INAF-OAB), W. H. Baumgartner (GSFC/UMBC), D. N. Burrows (PSU),
M. M. Chester (PSU), N. Gehrels (NASA/GSFC), C. Guidorzi (INAF-OAB),
S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU),
C. B. Markwardt (CRESST/GSFC/UMD), F. E. Marshall (NASA/GSFC),
P. T. O'Brien (U Leicester), D. M. Palmer (LANL),
P. Romano (INAF-IASFPA), T. N. Ukwatta (GSFC/GWU) and
D. E. Vanden Berk (PSU) report on behalf of the Swift Team:

At 12:26:13 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 080503 (trigger=310785).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 286.617, +68.778 which is 
   RA(J2000) = 19h 06m 28s
   Dec(J2000) = +68d 46' 41"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a single spike
structure with a duration of about 0.5 sec, although there may
be further activity during the slew.  The peak count rate
was ~6500 counts/sec (15-350 keV), at ~0.1 sec after the trigger. 

The XRT began observing the field at 12:27:28.1 UT, 74.9 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
fading, uncatalogued X-ray source with an enhanced position: RA, Dec
286.62049, 68.79379 which is equivalent to:
   RA(J2000)  = 19h 06m 28.92s
   Dec(J2000) = +68d 47' 37.6"
with an uncertainty of 2.7 arcseconds (radius, 90% containment). This
location is 57 arcseconds from the BAT onboard position, within the BAT
error circle. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of
5.56e+20 cm^-2 (Kalberla et al. 2005), so we cannot constrain the
redshift at this time using the relation from Grupe et al. (2007). A
summary of the promptly downlinked data is given at
http://www.swift.ac.uk/sper/310785/. 

The initial flux in the 2.5 s image was 7.82e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 100 seconds with the White (160-650 nm)
filter starting 84 seconds after the BAT trigger. No afterglow candidate has
been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of
the XRT error circle. The 3-sigma upper limit is about 20th mag. 
The 8'x8' region for the list of sources generated on-board covers 100% of the
XRT error circle. The list of sources is typically complete to about 18 mag. No
correction has been made for the expected extinction corresponding to E(B-V) of
0.06. 

Burst Advocate for this burst is J. Mao (jirong.mao AT brera.inaf.it). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB080503A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7666
SUBJECT: GRB 080503: Optical afterglow candidate and LRIS spectroscopy of the short burst
DATE:    08/05/03 13:22:34 GMT
FROM:    Daniel Perley at U.C. Berkeley  <dperley@astro.berkeley.edu>

D. A. Perley (UC Berkeley), D. Lai, C. Rockosi (UCSC/Lick), and J. S. 
Bloom (UC Berkeley) report:

After the GRB alert we slewed to the position with the Keck I telescope, 
equipped with LRIS.  We detect a possible new source at a position 
consistent with the XRT position in the LRIS guider camera near the 
detection limit of the guider (~20-21st mag).  Spectroscopic 
observations began at ~13:01 UT.  Results will be reported in 
forthcoming circulars.


GRB_name: GRB080503A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7667
SUBJECT: GRB 080503: New candidate afterglow/host in Gemini imaging
DATE:    08/05/03 15:30:13 GMT
FROM:    Daniel Perley at U.C. Berkeley  <dperley@astro.berkeley.edu>

J. S. Bloom and D. A. Perley (UC Berkeley) report on behalf of a larger 
collaboration:

We obtained a sequence of images of the field of GRB 080503 (Mao et al. 
GCN 7665) from Gemini North using GMOS. In a stack of five 180s 
exposures starting 2008-05-03 13:23:39 UT, we detect a faint source 
("s1") consistent with the Mao et al. XRT position at:

  19:06:28.694 +68:47:37.71 J2000

With a positional uncertainty of about 250 mas. Given the faintness of 
the source, we can claim neither variability nor that the source is 
pointlike, but it is possible that the source is the host and/or the 
afterglow. Note that s1 is not the source we originally identified as 
the possible afterglow in Perley et al. (GCN 7666); we now believe that 
that object identified in the Keck guider image was outside the XRT 
error circle and unrelated to the GRB.

This and other sources of interest near the XRT position are encircled 
in green in the finder:

       http://lyra.berkeley.edu/~jbloom/grb080503.png

We thank Rachel Mason of Gemini for her assistance.


GRB_name: GRB080503A
Detection_method: MITSuME
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7668
SUBJECT: GRB 080503: MITSuME Akeno optical upper limits
DATE:    08/05/03 16:35:16 GMT
FROM:    Nobuyuki Kawai at Tokyo Tech  <nkawai@hp.phys.titech.ac.jp>

Y.A. Mori, Y. Kudou, T. Shimokawabe and N. Kawai (Tokyo Tech) report on
behalf of the MITSuME collaboration: 

We observed the error box of GRB 080503 (Mao et al. GCN 7665)
with the 3-color 50cm MITSuME Telescope at Akeno, Japan starting
at 2008-05-03 12:31:53 UT, 5.4 min after the trigger.
In the co-added images of Ic, Rc, and g' bands, we did not detect
any afterglow candidate in the XRT error circle.  
The 3-sigma limiting magnitudes based on USNO-B1.0 (I-band) and NOMAD
(R-band,g'-band) stars are following.

Filter  start (UT)  end (UT)    Exposure   LimitMag
---------------------------------------------------
g'      12:31:53    12:41:03    9 x 60 s     18.8
Rc      12:31:53    12:41:03    9 x 60 s     19.2
Ic      12:31:53    12:41:03    9 x 60 s     18.1
----------------------------------------------------


GRB_name: GRB080503A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7669
SUBJECT: GRB 080503: Enhanced Swift-XRT position
DATE:    08/05/03 17:00:49 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 307 s of overlapping XRT Photon Counting mode and UVOT
data for GRB 080503, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 286.61961, +68.79330 which is equivalent
to:

RA (J2000): 19h 06m 28.71s
Dec (J2000): +68d 47' 35.9"

with an uncertainty of 1.8 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest position
can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is
described by Goad et al. (2007, A&A, 476, 1401
http://www.swift.ac.uk/xrt_positions/Goad.pdf), the current algorithm is an
extension of this method.

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB080430A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7670
SUBJECT: GRB 080430
DATE:    08/05/03 17:54:03 GMT
FROM:    Francois Kugel at Obs.Chante-Perdix,04 Banon,Fr  <fkugel@wanadoo.fr>

C.Rinner ; F.Kugel report:

We imaged the field of GRB 080430 detected by SWIFT
with the TEL 0.5-m f/3 reflector
located at Observatoire Chante-Perdix - 04 Banon, France (A77 mpc station)

The observations started at 21:33:18 (UT).
24 exposures of 120s were carried out and weather conditions
were good.

We observe a new source in the error box given by SWIFT
at the following position:

RA(J2000) = 11h 01m 14.76s
DEC(J2000) +51d 41' 08.3"
+/-0.3"

magnitude = 18.6 +/-0.3

Astrometry and magnitudes were measured with the  USNO-SA2.0 catalogue.

No change magnitude was observed during the one hour observation.

More information and pictures here :
http://pagesperso-orange.fr/fkometes/pages/GRB080430.html


GRB_name: GRB080430A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7671
SUBJECT: GRB 080430
DATE:    08/05/03 18:03:09 GMT
FROM:    Francois Kugel at Obs.Chante-Perdix,04 Banon,Fr  <fkugel@wanadoo.fr>

C.Rinner ; F.Kugel  report:

We are continuing with the monitoring of the afterglow (Klotz et al. GCN
7646) with the TEL 0.5-m f/3 reflector
located at Observatoire Chante-Perdix - 04 Banon, France (A77 mpc 
station, N43.9997 E5.6475)

The observations started at 20:39:12 (UT).
9 unfiltered exposures of 120s were carried out and weather conditions
were good.

We observe a weak reduction in magnitude

RA(J2000) = 11h 01m 14.76s
DEC(J2000) +51d 41' 08.3"
0.3"

magnitude = 19.6 0.3 one day after the burst.

Astrometry and magnitudes were measured with the  USNO-SA2.0 catalogue.

More information and picture here :

http://pagesperso-orange.fr/fkometes/pages/GRB080430.html


GRB_name: GRB080430A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7672
SUBJECT: GRB 080430
DATE:    08/05/03 18:14:17 GMT
FROM:    Francois Kugel at Obs.Chante-Perdix,04 Banon,Fr  <fkugel@wanadoo.fr>

C.Rinner ; F.Kugel  report:

May 02

We are continuing with the monitoring of the afterglow (Klotz et al. GCN
7646) with the TEL 0.5-m f/3 reflector
located at Observatoire Chante-Perdix - 04 Banon, France (A77 mpc
station, N43.9997 E5.6475)

The observations started at 20:21:42 (UT).36 unfiltered exposures of 120s were 
carried out; although weak the source is still visible (SNR = 4.4) on an 
addition of 28 exposuress (cloudy passages on the other images). Measured 
magnitude = 20.6 two day after the burst.

Astrometry and magnitudes were measured with the  USNO-SA2.0 catalogue.

More information and picture here :

http://pagesperso-orange.fr/fkometes/pages/GRB080430.html


GRB_name: GRB080503A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7673
SUBJECT: GRB 080503, Swift-BAT refined analysis
DATE:    08/05/03 20:02:48 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

T. Ukwatta (GWU), S. D. Barthelmy (GSFC), W. Baumgartner (GSFC/UMBC),
J. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC),
H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), K. McLean (GSFC/UMD),
J. Mao (INAF-OAB), D. Palmer (LANL), T. Sakamoto (GSFC/UMBC),
G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC)
(i.e. the Swift-BAT team):
 
Using the data set from T-239 to T+963 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 080503 (trigger #310785)
(Mao, et al., GCN Circ. 7665).  The BAT ground-calculated position is
RA, Dec = 286.686, 68.803 deg, which is 
   RA(J2000)  =  19h 06m 44.7s 
   Dec(J2000) = +68d 48' 09.2" 
with an uncertainty of 3.5 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 75%.
 
The mask-weighted light curve shows an initial spike starting at ~T+0.1 sec
with a fast rise to a peak at ~T+0.2 sec, with a roughly exponential decay
down to background at ~T+0.7 sec.  The softer emission starts at about T+10 sec,
rising with two peaks at about T+26 and +37 sec, and then falling to background
levels at T+220+/-20 sec.  T90 (15-350 keV) is 170 +- 40 sec (estimated error
including systematics).
 
The time-averaged spectrum from T+0.2 to T+220.6 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
2.00 +- 0.13.  The fluence in the 15-150 keV band is 2.0 +- 0.1 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+26.58 sec in the 15-150 keV band
is 0.9 +- 0.1 ph/cm2/sec.  All the quoted errors are at the 90% confidence level.

As to whether this burst is a SHB with extended emission or a Long burst
with a particularly short pulse at the beginning, we can not say yet.  Looking
at the 4-band lightcurves, the initial spike is harder than the later emission.
We are waiting for (a) separate spectral analysis on the two portions
of the lightcurve, and (b) for the lag analysis.  We are currently in an 8-hour
gap in the downlink sessions, so it will be a while before we can say
with better confidence if this is truely a SHB or not.  We will issue
another circular.
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/310785/BA/


GRB_name: GRB080503A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7674
SUBJECT: GRB080503 XRT refined analysis
DATE:    08/05/03 22:52:44 GMT
FROM:    Jirong Mao at INAF-OAB  <jirong.mao@brera.inaf.it>

GRB 080503: Swift-XRT refined analysis


C. Guidorzi & J. Mao (INAF-OAB) report on behalf of the Swift-XRT team:

The Swift-XRT began observing GRB 080503 (trigger=310785, Mao et
al., GCN Circ. 7665) in Window Timing mode, 81 s after the BAT
trigger. The enhanced XRT position was given in Goad et al.
(GCN Circ. 7669).

The light curve from 81 s to 13.2 ks can be modelled with
the combination of an exponential with
a power law taking over at late time, with the following
best-fitting parameters: e-folding time= (72  4) s, power-law
index alpha= 2.2 (-1.1, +0.6). The chisq/dof=202/151 is due to
short-term variability superposed to the model.

The WT mode spectrum spanning from 81 to 282 s can be fit by a
power-law model, with a photon index of 1.27  0.03 and column
density consistent with the average Galactic column density in
this direction of 5.6e20 cm^-2.
The PC mode spectrum, starting from 282 s and totalling 6.3 ks
of exposure, is fit with a power law with a photon index of 2.45+/-0.25
and no evidence for any additional column density with respect
to the Galactic one.
The corresponding observed (unabsorbed) 0.3-10 keV flux is 2.9e-12
(3.9e-12) erg cm^-2 s^-1.

If the burst continues to decay at the same rate, we predict an
XRT count rate of 1.7e-6 count/s at T+24 hours, which corresponds
to an observed 0.3-10 keV flux of approximately 4e-17 erg cm^-2 s^-1.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB080503A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7675
SUBJECT: GRB080503: Swift/UVOT Upper Limits
DATE:    08/05/04 01:23:57 GMT
FROM:    Peter Brown at PSU  <pbrown@astro.psu.edu>

P. J. Brown (PSU) and J. Mao(INAF-OAB),
on behalf of the Swift/UVOT team.

The Swift Ultra-Violet/Optical Telescope (UVOT)
began settled observations of GRB 080503 (trigger 310785)
84 seconds after the BAT trigger (Mao et al.,GCN Circ. 7639).
No afterglow is detected at the enhanced XRT position
(Goad et al., GCN Circ. 7665) in the initial white finding chart
or subsequent summed images. The limiting magnitudes
(3-sigma in 5" radius apertures) in each of the UVOT filters
are as follows:

Filter  T_start(s)  T_stop(s)  Exp(s)  Mag UL (3sig)

white       85       184        98     >20.0
white       85     12500      1314     >22.3
v          191      6749      1219     >20.5
b          671     11588      1203     >21.4
u          646      7365       471     >20.3
uvw1       622      7160       471     >20.4
uvm2       597      6954       471     >20.3
uvw2       701     13219      1133     >21.0

The values quoted above are in the UVOT photometric system
(Poole et al. 2008, MNRAS, 383, 627).  They are not corrected
for the expected Galactic extinction corresponding to a
reddening of E(B-V)=0.06 mag in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB080503A
Detection_method: MITSuME
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7676
SUBJECT: GRB 080503: MITSuME Ishigakijima optical upper limits
DATE:    08/05/04 03:04:00 GMT
FROM:    Nobuyuki Kawai at Tokyo Tech  <nkawai@hp.phys.titech.ac.jp>

D. Kuroda, K. Yanagisawa (NAOJ) and N. Kawai (Tokyo Tech) report on
behalf of the MITSuME collaboration: 

We observed the error box of GRB 080503 (Mao et al. GCN 7665) with the
3-color 105cm Telescope at Ishigakijima Astronomical Observatory
starting at 2008-05-03 13:49:55 UT, 1.4 hours after the trigger.
In the co-added images of Ic, Rc, and g' bands, we did not detect any
afterglow candidate.  The 3-sigma limiting magnitudes based on
USNO-B1.0 (I-band) and NOMAD (R-band,g'-band) stars are following.

Filter  start (UT)  end (UT)    Exposure   LimitMag
---------------------------------------------------
g'      13:49:55    13:59:19    9 x 60 s     20.5
Rc      13:49:55    13:59:19    9 x 60 s     20.2
Ic      13:49:55    13:59:19    9 x 60 s     20.1
----------------------------------------------------


GRB_name: GRB080503A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7677
SUBJECT: GRB 080503, Swift-BAT lag and time-resolved spectral analysis
DATE:    08/05/04 18:39:40 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

T. Ukwatta (GWU), M. Stamatikos (GSFC/ORAU), T. Sakamoto (GSFC/UMBC),
J. Norris (U. of Denver), S. D. Barthelmy (GSFC)
(for the Swift-BAT team):
 
For GRB 080503 (Trigger 310785, GCNs 7665 & 7673),
the spectral lag analysis of the data from T-1 sec to T+1 sec
(the initial spike), yields a lag of -13 +/- 9 msec for the
15-25 to 50-100 keV bands using lightcurve binnings of 4, 8 and 16 msec.
For the on-going emission (T+10 to T+220 sec), the signal is too weak
and lacking sufficient structure to yield a significant lag measurement.

Expanding on the total-burst spectral analysis in GCN 7673,
we have divided the burst into an initial phase (T+0.0 to T+0.7 sec)
and the extended phase (T+10 to T+170 sec).  The simple power law fits are:
  Phase     PLI            Norm(@50keV)         Chi2/DoF
  Initial   1.59 +/-0.28  (8.15 +- 1.5)E-3      69/59
  Extended  1.91 +/-0.12  (1.19 +- 0.08)E-3     52/59
The units of Normalization are ph/cm2/s/keV.

This lag value plus the spectral results puts this burst
in the short hard burst category.


GRB_name: GRB080503A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7678
SUBJECT: GRB 080503: Late-time Optical rebrightening (possible mini-SN)
DATE:    08/05/05 04:49:49 GMT
FROM:    Daniel Perley at U.C. Berkeley  <dperley@astro.berkeley.edu>

D. A. Perley, J. S. Bloom (UC Berkeley), and J. X. Prochaska (UCO/Lick) 
report:

Further to Bloom et al. (GCN 7667), we acquired additional imaging of 
the probable short-hard (Ukwatta et al., GCN 7677) GRB 080503 (Mao et 
al., GCN 7665) with extended emission the night after the burst.   A 
total of 10 exposures of 180 seconds each were taken in r-band between 
UT 14:08 and 14:46 (2008-05-04), 26 hours after the BAT trigger, using 
GMOS on Gemini-North.  In addition, we report analysis of additional 
imaging taken between 1.0-2.5 hours after the burst in g, r, i, and z 
filters.

The source noted in our previous circular, s1, does not appear to be 
variable between images, and no other sources are detected in the XRT 
error circle to a very deep limit of r >~ 26.5 during the first night. 
However, a new source ("s2") appears in the second night's observation 
that was not detected in our r-band imaging during the first night.  If 
this source is associated with GRB 080319B this would be extremely 
unusual behavior for a short gamma-ray burst.  It is possible that the 
rebrightening is the first example of the detection of a Li-Paczynski 
"mini"-supernova (1998ApJ...507L..59L; see also Kulkarni 
astro-ph/0510256). More tentatively, we note that s1 may the host galaxy 
(we note that all previous SHB's with extended emission have been seen 
at small offset from their host galaxies: Troja et al., astro-ph/0711.3034).

The source is located near the center of the enhanced XRT error circle 
(Goad et al, GCN 7669) at:

RA=19:06:28.766  Dec=+68:47:35.53 (J2000)

(uncertainty is 250 mas in both coordinates relative to the ICRS)

And can be seen at the following links:
http://lyra.berkeley.edu/~jbloom/grb080503-comp.png
http://lyra.berkeley.edu/~jbloom/grb080503-rebrightening.mpeg
http://lyra.berkeley.edu/~dperley/080503/080503_s2b.png

We report the following photometry, calibrated relative to USNO-B1.0:

Acquisition r-band image (t=0.98 hr)
s1: R = 25.56 +/- 0.33
s2: R > 25.6

First night r-band stack (t=1.5 hr)
s1: R = 26.00 +/- 0.18
s2: R >~ 26.5

Second night r-band stack (t=26.0 hr)
s1: R = 25.70 +/- 0.12
s2: R = 25.28 +/- 0.09

UT_start exposure   filter magnitude
13:23    1x180      r      R = 24.8 +/- 0.3
13:38    1x30+2x300 R      R > 25.5 (2-sigma)
13:47    5x180      r      R = 25.4 +/- 0.2

Photometric uncertainties do not include calibration uncertainties 
relative to USNO-B1.0, which are at the level of 0.1 magnitude.  (This 
does not affect the relative magnitudes between the images).

In our images in other filters, s2 is not detected in i-band or z-band 
during the first night.  It may be marginally detected in g-band imaging 
near the limiting magnitude of that observation.

Further observations of this source are planned and strongly encouraged.


GRB_name: GRB080503A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7679
SUBJECT: GRB 080503: Late-time Optical rebrightening (possible mini-SN) - correction
DATE:    08/05/05 05:00:21 GMT
FROM:    Daniel Perley at U.C. Berkeley  <dperley@astro.berkeley.edu>

D. A. Perley, J. S. Bloom (UC Berkeley), and J. X. Prochaska (UCO/Lick)
report:

The line that states:

"If this source is associated with GRB 080319B this would be extremely 
unusual behavior for a short gamma-ray burst."

Should of course read:

"If this source is associated with GRB 080503 this would be extremely 
unusual behavior for a short gamma-ray burst."

We apologize for any confusion, and thank R. Chornock for pointing out 
the error.


GRB_name: GRB080503A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7680
SUBJECT: GRB 080503: No further optical rebrightening
DATE:    08/05/05 13:15:41 GMT
FROM:    Daniel Perley at U.C. Berkeley  <dperley@astro.berkeley.edu>

D. A. Perley and J. S. Bloom (UC Berkeley) report on behalf of a larger 
collaboration:

Starting at UT 11:32 on the night of 2008-05-05, we began a series of 
additional r-band imaging follow-up observations of the optical 
counterpart associated with GRB 080503 (GCN 7665, Mao et al.), using 
Gemini-North (+GMOS).

The new source (s2) reported in our previous circular (GCN 7678) is 
still present at about the same magnitude.  Using a stack of 9x180s 
images, we present the following measurement of the magnitudes of s1 and s2:

s1: R = 26.33 +/- 0.20
s2: R = 25.46 +/- 0.09

This is consistent (within about 2-sigma) with the previous night's 
measurement and suggests neither additional rebrightening nor dramatic 
fading.  We continue to strongly encourage follow-up with large-aperture 
instruments.


We also issue the following correction to GCN 7678: the data table at 
the bottom (with heading "UT_start exposure filter magnitude") is not 
valid.  This is photometry of s1 based on an older calibration, and 
including a Keck R-band limiting magnitude that will be refined in a 
future circular.  The preceding photometry of s1 and s2 in that circular 
is still valid.

To reiterate, the r-band evolution of the optical counterpart (s2) to 
date, calibrated to USNO B1.0 R-band, is given by:

t(hr)  magnitude
0.98   R > 25.6
1.5    R > 26.5
26.0   R = 25.28 +/- 0.09
47.4   R = 25.46 +/- 0.09

Further observations are ongoing.


GRB_name: GRB080430A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7681
SUBJECT: GRB 080430: TLS imaging one day after the GRB
DATE:    08/05/05 20:00:39 GMT
FROM:    Alexander Kann at TLS Tautenburg  <kann@tls-tautenburg.de>

D. A. Kann, F. Ludwig, R. Filgas and S. Klose (TLS tautenburg) report:

We imaged the afterglow (Klotz et al., GCN 7646) of GRB 080430 (Guidorzi 
et al., GCN 7647) with the TLS Schmidt telescope one day after the GRB. 
Direct RRM observations a day earlier were unobtainable due to persistent 
bad weather. We obtained 22 180 second images starting with twilight under 
good conditions and at airmass 1. The afterglow is visible on all single 
images.

From the SDSS photometry of the field (Cool et al., GCN 7649), we find 
that the bright star southeast of the afterglow, at R.A. = 11:01:16.88, 
Dec. = +51:40:38.6 has g = 17.111, r = 16.539 and i = 16.377. Using the 
transformations of Jester et al. 2005, we find Rc = 16.458 for this star. 
Using it as a comparison star, we derive for the afterglow from a stack of 
all images:

time after burst Rc dRc

1.020536 days  21.20 0.06

This is in good agreement with the slightly later measurement of Khamitov 
et al. (GCN 7661) but significantly fainter than the magnitude reported by 
Pandey et al. (GCN 7663) for an observation a few hours earlier.

Data analysis was delayed by access problems.

This message may be cited.


GRB_name: GRB080503A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7682
SUBJECT: GRB 080503: Slow-rise optical AG ? 
DATE:    08/05/06 03:50:15 GMT
FROM:    Arnon Dar at Technion-Israel Inst. of Tech  <arnon@physics.technion.ac.il>

Many long GRBs have optical light-curves which are initially slowly 
rising. The optical light curve of the short hard burst (SHB) 080503 (Mao 
et al. GCN 7665; Ukwatta et al. GCN 7673; Guidorzi et al. GCN 7674) 
discovered by Perley et al. (GCNs 7678, 7680) may be their analog 
slow-rise optical afterglow (AG) changing to a plateau phase and entering 
the gradual transition to an asymptotic decline, which, in the CB model, 
has roughly the form,

            Fnu ~ [1/(t+t_b}^{\beta_O+1/2}] * nu^{-beta_O}

for a constant low-density SHB environment, or

            Fnu  ~ [1/ (t+t_b)^{beta_O+1}] * nu^{-beta_O}

for an isothermal sphere environment with a density propto 1/r^2.
t_b is the bending time of its canonical AG, and beta_O = Gamma - 1 ~ 1.1 is 
the spectral index above the bend frequency. In the CB model, the initial 
increase of the CB's radius, R^2 ~ t^2/(t^2+t_exp^2), where t_exp is the time 
beyond which the CB's radius settles to its approximate constant value, 
produces the initial rise of the synchrotron AG.  The low density environments 
of SHBs yields typically, t_b~ 10^5 s, and a long expansion time, t_exp, of the 
CB's radius relative to its values in slow-rise optical AGs of long GRB such as 
071010A (Covino et el. arXiv:0804.4367).


GRB_name: GRB080503A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7683
SUBJECT: GRB 080503: Observations from NOT
DATE:    08/05/06 04:45:03 GMT
FROM:    Antonio Deugarte at IAA-CSIC  <deugarte@iaa.es>

A. de Ugarte Postigo, (ESO), C. C. Thne, D. Malesani,
J. P. U. Fynbo (DARK) and T. Purismo (NOT) on behalf
of a larger collaboration report:

We have observed the field of GRB 080503 (Mao et al.,
GCN 7665) from the 2.5m NOT (+MOSCA) under bad
atmospheric conditions. We do not detect the object reported
by Perley et al. (GCN 7678) down to a  3-sigma limiting
magnitude of R~21.7 at a mean time of 6.091 May 2008 UT
(2.573 days after the burst).


GRB_name: GRB080503A
Detection_method: VLA Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7684
SUBJECT: GRB 080503: VLA radio upper limit
DATE:    08/05/06 17:37:33 GMT
FROM:    Poonam Chandra at U Virginia/NRAO  <pc8s@virginia.edu>

Dale A. Frail (NRAO) and Poonam Chandra (NRAO/UVA) report on behalf
of the Caltech-NRAO-Carnegie GRB Collaboration:

"We used the Very Large Array to observe the field of view toward GRB
080503 (GCN 7665) at a frequency of 8.46 GHz at 2008 May 6.57 UT.
We do not detect the GRB afterglow in 2.5 hours of VLA observations.
The 3-sigma upper limit on the afterglow flux is 54 uJy (rms 18 uJy).

The National Radio Astronomy Observatory is a facility of the National
Science Foundation operated under cooperative agreement by Associated
Universities, Inc."


GRB_name: GRB080506A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7685
SUBJECT: GRB 080506: Swift detection of a burst with optical afterglow
DATE:    08/05/06 18:06:27 GMT
FROM:    Wayne Baumgartner at GSFC  <wayne@milkyway.gsfc.nasa.gov>

W. H. Baumgartner (GSFC/UMBC), D. N. Burrows (PSU),
M. M. Chester (PSU), G. Cusumano (INAF-IASFPA),
P. A. Evans (U Leicester), N. Gehrels (NASA/GSFC),
C. Guidorzi (INAF-OAB), S. T. Holland (CRESST/USRA/GSFC),
S. Immler (CRESST/GSFC/UMD), J. A. Kennea (PSU),
V. La Parola (INAF-IASFPA), V. Mangano (INAF-IASFPA),
F. E. Marshall (NASA/GSFC), P. T. O'Brien (U Leicester),
C. Pagani (PSU), P. Romano (INAF-IASFPA), T. Sakamoto (NASA/UMBC),
M. Stamatikos (NASA/ORAU), T. N. Ukwatta (GSFC/GWU) and
H. Ziaeepour (UCL-MSSL) report on behalf of the Swift Team:

At 17:46:21 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 080506 (trigger=311159).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 329.435, +39.002 which is 
   RA(J2000) = 21h 57m 44s
   Dec(J2000) = +39d 00' 08"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  As this is an image trigger, the BAT light curve does 
not show meaningful emission from the burst. 

The XRT began observing the field at 17:48:41.3 UT, 140.1 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
uncatalogued X-ray source located at RA, Dec 329.42145, 38.98413 which
is equivalent to:
   RA(J2000)  = 21h 57m 41.15s
   Dec(J2000) = +38d 59' 02.9"
with an uncertainty of 3.3 arcseconds (radius, 90% containment). This
location is 74 arcseconds from the BAT onboard position, within the BAT
error circle. The XRT light curve from TDRSS data is fading. 

A power-law fit to a spectrum formed from promptly downlinked event
data does not constrain the column density, so we cannot provide limits
on the redshift using spectroscopy and the relation from Grupe et al. 
(2007). A summary of the promptly downlinked data is given at
http://www.swift.ac.uk/sper/311159/. 

The initial flux in the 2.5 s image was 5.50e-09 erg cm^-2 s^-1 (0.2-10
keV). 


UVOT took a finding chart exposure of 400 seconds with the V filter starting
143 seconds after the BAT trigger. There is a candidate afterglow in the
rapidly available 2.7'x2.7' sub-image at
  RA(J2000)  = 21:57:41.83 = 329.4243
  DEC(J2000) = +38:59:06.4  =  38.9851
with a 1-sigma error radius of about 0.5 arc sec. This position is 8.0 arc sec. 
from the center of the XRT error circle. The estimated magnitude is 18.3 with a
1-sigma error of about 0.5 mag. No correction has been made for the expected
extinction of about 0.8 magnitudes. 

Burst Advocate for this burst is W. H. Baumgartner (wayne AT milkyway.gsfc.nasa.gov). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB080506A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7686
SUBJECT: GRB 080506: Optical observation with KANATA/TRISPEC
DATE:    08/05/06 20:56:40 GMT
FROM:    Koji Kawabata at HASC,Hiroshima U  <kawabtkj@hiroshima-u.ac.jp>

K. S. Kawabata, M. Sasada, M. Uemura, T. Yamashita and T. Ohsugi
(Hiroshima Univ.) and R. G. Lundock (Tohoku Univ.) report on behalf
of KANATA/TRISPEC observation team:

  We performed a series of simultaneous optical(Rc) and NIR (J, Ks)
imaging observations for the optical counterpart associated with
GRB 080506 (Baumgartner et al, GCN 7685) using TRISPEC attached to 
the 1.5-m KANATA telescope. Our quick-look analysis showed that Rc
magnitude of the counterpart was 17.5 at 220 sec after the BAT
trigger. It then faded and reached 19.5 at ~5050 sec. We used USNO
A2.0 1275-16800533 (R=15.1) and 1275-16801542 (R=15.1) stars for
comparison. Further analysis is ongoing.


GRB_name: GRB080506A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7687
SUBJECT: GRB 080506: Enhanced Swift-XRT position
DATE:    08/05/07 03:31:53 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 221 s of overlapping XRT Photon Counting mode and UVOT
data for GRB 080506, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 329.42431, +38.98470 which is equivalent
to:

RA (J2000): 21h 57m 41.83s
Dec (J2000): +38d 59' 04.9"

with an uncertainty of 1.5 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest position
can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is
described by Goad et al. (2007, A&A, 476, 1401
http://www.swift.ac.uk/xrt_positions/Goad.pdf), the current algorithm is an
extension of this method.

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB080506A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7688
SUBJECT: GRB 080506: TLS afterglow detection in VRIZ
DATE:    08/05/07 04:02:27 GMT
FROM:    Alexander Kann at TLS Tautenburg  <kann@tls-tautenburg.de>

D. A. Kann, C. Hoegner and S. Ertel (TLS Tautenburg) report:

We observed the afterglow of Swift GRB 080506 (Baumgartner et al., GCN 
7685, Kawabata et al., GCN 7686) with the Tautenburg 1.34m Schmidt 
telescope 0.32 days after the GRB in good conditions (moderate 
transparency but excellent seeing). We obtained a total of six 600 sec 
exposures, in the sequence Rc, V, Ic, Z, Z, Z before twilight forced us to 
shut down. The afterglow is well (Rc, V, Ic) and faintly (Z) detected in 
single images, and well detected in the 1800 sec stack of the three Z 
images.

We find an afterglow position

R.A. (J2000) = 21:57:41.775
Dec. (J2000) = +38:59:05.86

in comparison with the USNOB1.0 catalog, with a precision of 0".5 in each 
coordinate. This is fully in agreement with the UVOT (Baumgartner et al., 
GCN 7685) and enhanced XRT (Osborne et al., GCN 7687) positions.

Assuming the star at

R.A. (J2000) = 21:57:39.84
Dec. (J2000) = +38:58:28.25

to have Rc = 16.7 (magnitude is basically identical in R1 and R2 
magnitudes), we find for the afterglow:

time Rc dRc

0.31576 20.77 0.13

Taking the two measurements from Kawabata et al. (GCN 7686), we find a 
shallow decay slope of alpha = 0.6 between 0.0025 and 0.316 days after the 
GRB.

Our (and Swift's) clear detection in the V band implies z <~ 4. On the 
other hand, this was an image trigger, with faint emission seen up to ~ 
200 seconds. The initial XRT light curve (XRT repository, Evans et al. 
2007) is flat until 200 seconds before dropping off very steeply. This may 
suggest that this GRB lies at moderately high redshift (3 - 4). 
Spectroscopy is encouraged.

This message may be cited.


GRB_name: GRB080506A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7689
SUBJECT: GRB 080506: optical observation from Ondrejov
DATE:    08/05/07 05:09:29 GMT
FROM:    Matus Kocka at Monteboo Obs,Masaryk U,Brno  <koci@astronom.sk>

M. Kocka, M. Nekola, J. Strobl, R. Hudec, C. Polasek (AsU AV CR, Ondrejov),
M. Jelinek, P. Kubanek (IAA CSIC, Granada),
F. Munz (IASF/INAF, Bologna) A. de Ugarte Postigo (ESO) report

We observed the OT of the GRB080506 (Baumgartner et al,
GCN 7685) with the 0.5m telescope at ASU Ondrejov in
Czech Republic. We obtained a set of R-band exposures
at ~7.1h after the GRB.

Using the same calibration as Kawabata et al. (GCN 7686) we find the 
brightness R ~ 21.2+-0.4.

This message may be cited.


GRB_name: GRB080506A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7690
SUBJECT: GRB 080506: Observations from NOT
DATE:    08/05/07 05:51:42 GMT
FROM:    Antonio Deugarte at IAA-CSIC  <deugarte@iaa.es>

A. de Ugarte Postigo (ESO), C. C. Thoene,
J. P. U. Fynbo (DARK/NBI),  E. Leitet (Uppsala Univ.) and
L. M. Trinchant (Stockholm Univ.) report on behalf of a
larger collaboration:

We have observed the field of GRB 080506 (Baumgartner
et al., GCN 7685) using the 2.5m NOT telescope (+ALFOSC)
at Roque de Los Muchachos Observatory, in La Palma (Spain)
using U, B and R filters. A 300s R-band observation with
mid exposure time 7.1518 May 2008 UT (9.87hr after the burst)
reveals the object at a magnitude of 21.05  0.11, using the
reference stars given in GCN 7686 for calibration. Combining
this datapoint with those of Kawabata et al. (GCN 7686),
Kann et al. (GCN 7688) and Kocka et al. (GCN 7689, where
it should say R= 20.2+/-0.4, private communication) we measure
a decay rate of  alpha = 0.64  0.02 (f~t^-alpha), consistent with
the value reported by Kann et al. The object is clearly detected in
all filters, including the U-band frame, implying a redshift < 3.


GRB_name: GRB080503A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7691
SUBJECT: GRB080503, RIMOTS optical upper limit
DATE:    08/05/07 07:44:10 GMT
FROM:    Hiroki Tanaka at U of Miyazaki  <hiro0218@astro.miyazaki-u.ac.jp>

H. Tanaka, N. Ohmori, H. Hayasi, R. Hara, K. Kono, M. Yamauchi
(University of Miyazaki)

We have observed the field covering the error circle of
GRB080503 (GCN 7669, M.R. Goad et al.) with
the unfiltered CCD camera on the 30-cm telescope at
University of Miyazaki.
The observation was started 15:25:55 UT; about 180 minutes
after the Swift trigger time.

We have compared our data of 30 sec exposures
with the USNO-A2.0 catalog,there is no new source
at the reported position

the upper limits are as follows:
--------------------------------------------------------------
Start(UT) End(UT) Num. of frames  Limit (mag.)
--------------------------------------------------------------
15:26:57 15:27:27  1   ~16.82
15:26:57 16:24:33  57   ~17.43
---------------------------------------------------------------


GRB_name: GRB080506A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7692
SUBJECT: GRB 080506, Swift-BAT refined analysis
DATE:    08/05/07 14:23:57 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

K. McLean (GSFC/UMD), S. D. Barthelmy (GSFC), W. Baumgartner (GSFC/UMBC),
J. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC),
H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), D. Palmer (LANL),
T. Sakamoto (GSFC/UMBC), G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU),
J. Tueller (GSFC), T. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-239 to T+903 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 080506 (trigger #311159)
(Baumgartner, et al., GCN Circ. 7685).  The BAT ground-calculated position is
RA, Dec = 329.467, 38.961 deg, which is 
   RA(J2000)  =  21h 57m 52.1s 
   Dec(J2000) = +38d 57' 40.0" 
with an uncertainty of 2.5 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 60%.
 
The mask-weighted light curve shows two episodes of emission, the first
starting at ~T+20 sec, peaking at ~T+40 sec, and returning to background
at ~T+90 sec.  The second episode starts at ~T+100 sec, peaks at ~T+150 sec,
and ends at ~T+200 sec.  T90 (15-350 keV) is 150 +- 20 sec
(estimated error including systematics).
 
The time-averaged spectrum from T+25.8 to T+188.8 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.87 +- 0.19.  The fluence in the 15-150 keV band is 1.3 +- 0.2 x 10^-06 erg/cm2.
The 1-sec peak photon flux measured from T+134.48 sec in the 15-150 keV band
is 0.4 +- 0.1 ph/cm2/sec.  All the quoted errors are at the 90% confidence level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/311159/BA/
 
This burst satisfies Sakamoto/Ukwatta Swift-BAT possible high-z criteria
(Ukwatta et al. arXiv:0802.3815):
1) PL photon index = 1.87          (PL photon index < 2)
2) 1-s peak photon flux = 0.4      (1-s peak photon flux < 1.0 ph/cm2/s)
3) Light curve variance = 6.2x10-6 (Variance < 0.0001)
4) T90/(Peak photon flux) = 403    (T90/(Peak photon flux) > 100)
Based on a limited sample of bursts, these criteria yield
an 85% chance it has a redshift greater than 3.5.  


GRB_name: GRB080506A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7693
SUBJECT: GRB080506: Swift/UVOT observations
DATE:    08/05/07 16:22:15 GMT
FROM:    Samantha Oates at MSSL  <sro@mssl.ucl.ac.uk>

S.R. Oates (MSSL/UCL) and W. Baumgartner (NASA/GSFC) report on behalf of 
the Swift/UVOT team

The Swift/UVOT began settled observations of the field of GRB 080506, 143s 
after the BAT trigger (Baumgartner et al., GCN 7685). We detect the 
afterglow in the v and b filters at the position:

RA(J2000)  =   21:57:41.84
DEC(J2000) =  +38:59:06.1

with an estimated uncertainty of 0.5 arcsec (radius, 90% confidence).
This position is consistent with the UVOT enhanced XRT position (Osborne 
et al., GCN 7687) and the TLS position (Kann et al., GCN 7688).

No observations were performed with the white filter due to the presence 
of 7.5mag B star (HD 208837) 6 arcmins from the GRB position.

UVOT magnitudes and 3 sigma upper limits are reported below for the single
and coadded images:

Filter    Tstart(s)  Tstop   Expo(s)   Magnitude/3sigUL
-----------------------------------------------------
v            143     543     393       18.35 +/- 0.10
v           6728    6928     197       19.88 +/- 0.52
b            623     771      19       19.84 +/- 0.65 (1.7-sigma)
b          10818   11118     295       20.64 +/- 0.28 (3.8-sigma)
u            599    6311     254       > 20.29
w1           574    7338     471       > 20.44
m2          1284    7133     787       > 20.69
w2           639    6723     432       > 20.46
-----------------------------------------------------

These magnitudes are not corrected for the Galactic extinction
corresponding to a reddening of E{B-V} = 0.23 mag (Schlegel et al.
1998). The photometry is on the UVOT flight system described in Poole
et al. (2008,MNRAS,383,627).


GRB_name: GRB080506A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7694
SUBJECT: GRB 080506: Swift XRT refined analysis
DATE:    08/05/07 17:49:36 GMT
FROM:    Boris Sbarufatti at INAF-IASF-Pa  <sbarufatti@ifc.inaf.it>

B. Sbarufatti, V. Mangano, V. La Parola (INAF-IASF PA) and
W. H. Baumgartner (GSFC/UMBC)

The Swift-XRT began observing GRB 080506 (trigger=311159, Baumgartner
et al., GCN Circ. 7685) in Window Timing mode, 146 s after the BAT
trigger. The enhanced XRT position was given in Osborne et al.
(GCN Circ. 7687).

The lightcurve is quite complex. It shows two initial bright flares
centered at 182+/-2 s and 254+/-2 s, with folding times of 22+/-1 s
and 88+/-2 s, respectively. Flaring activity is detected until times
 > T+10 ks. The decay slope after 10 ks from the trigger time is
-0.6+/-0.2.

The spectrum of the first flare can be fit by a power-law model, with
a photon index of 1.46  0.06 and column density consistent with the
average Galactic column density in this direction of 1.66e21 cm-2
(Kalberla et al 2005). The observed (unabsorbed) 0.3-10 keV flux is
1.5e-9 (1.8e-9) erg cm-2 s-1.

The spectrum of the second flare can be fit by a power-law model, with
a photon index of 2.3  0.1 and column density consistent with the
average Galactic column density in this direction. The observed
(unabsorbed) 0.3-10 keV flux is 3.2e-10 (5.2e-9) erg cm-2 s-1.

The PC mode spectrum, covering times > T+1000 s, is fit by a power
law model with photon index 2.0  0.2 and no evidence for any
additional column density with respect to the Galactic one.
The corresponding observed (unabsorbed) 0.3-10 keV fluxes are
2.3e-12 (3.5e-12 ) erg cm-2 s-1, respectively.

If the burst continues to decay at the same rate, we predict an XRT
count rate of 9.8 e-3 counts/s and 6.4 e-3 counts/s at T+24 hours
and T+48 hours, respectively. This corresponds to observed 0.3-10
keV fluxes of approximately 5.4e-13 and 3.6e-13 erg cm-2 s-1.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB080503A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7695
SUBJECT: GRB 080503: Fading in continued Gemini imaging
DATE:    08/05/07 18:31:25 GMT
FROM:    Daniel Perley at U.C. Berkeley  <dperley@astro.berkeley.edu>

D. A. Perley, J. S. Bloom, and W. Li (UC Berkeley), on behalf of a 
larger collaboration, report:

We have continued to monitor the optical transient (Perley et al., GCN 
7678) associated with GRB 080503 (Mao et al., GCN 7665) using Gemini-N 
(+GMOS) with additional exposures in r-band nightly since the event.

The optical counterpart remains detected in all images to date (through 
2008-05-07 UT) and is significantly, but slowly, fading.  This confirms 
the lack of further rebrightening (see also Perley et al., GCN 7680) and 
further distinguishes the behavior of the transient from ordinary long- 
and short-burst afterglows.  Alternatively, a faint host galaxy could be 
contributing to the later exposures somewhat; further follow-up may help 
resolve this ambiguity.


GRB_name: GRB080506A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7696
SUBJECT: GRB 080506: TLS 2nd Epoch - possible light curve break
DATE:    08/05/08 03:18:02 GMT
FROM:    Alexander Kann at TLS Tautenburg  <kann@tls-tautenburg.de>

D. A. Kann, C. Hoegner, and S. Ertel (TLS Tautenburg) report: 

We observed the afterglow of Swift GRB 080506 (Baumgartner et al., GCN 
7685) with the Tautenburg 1.34m Schmidt telescope 1.33 days after the GRB, 
again in good conditions. We obtained a four 300 sec exposures in the Rc 
band before twilight shut us down. The afterglow is faintly detected in 
the stacked image.

Using the same comparison star as Kann et al. (GCN 7688), we find:

time (days) Rc dRc

1.3346  22.23 0.33

An extrapolation of the decay in the first 0.4 days (~0.63, Kann et al., 
GCN 7688, de Ugarte Postigo et al., GCN 7690) yields an expected magnitude 
of Rc ~ 21.8 at 1.33 days after the GRB. Our measured value lies below the 
extrapolation, indicating a break (possibly a jet break) may have occured. 
We caution that the detection is rather marginal and the high sky 
background may falsify the measurement.

This message may be cited.


GRB_name: GRB080507A
Detection_method: superAGILE
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7697
SUBJECT: GRB 080507: GRB localization by SuperAGILE 
DATE:    08/05/08 12:14:50 GMT
FROM:    Marco Feroci at IASF/INAF  <feroci@iasf-roma.inaf.it>

Subject: GRB 080507: Gamma Ray Burst Localization by SuperAGILE

I. Lapshov, E. Costa, E. Del Monte, I. Donnarumma, Y. Evangelista, 
M. Feroci, F. Lazzarotto, L. Pacciani, M. Rapisarda, P. Soffitta, 
(INAF/IASF Rome), A. Giuliani, S. Vercellone, A. Chen, S. Mereghetti, A. 
Pellizzoni, F. Perotti, F. Fornari, M. Fiorini, P. Caraveo
(INAF/IASF Milan), A. Bulgarelli, F. Gianotti, M. Trifoglio, 
G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, 
M. Galli, (INAF/IASF Bologna), M. Tavani, G. Pucella, F. D'Ammando, V. 
Vittorini, A. Argan, A. Trois (INAF/IASF Rome), G. Barbiellini, 
F. Longo (INFN Trieste), P. Cattaneo (INFN Pavia), P. Picozza, A. Morselli 
(INFN Roma-2), M. Prest, E. Vallazza (Universita' dell'Insubria), P. 
Lipari, D. Zanello (INFN Roma-1), and  P. Giommi, C. Pittori, B. Preger, 
F. Verrecchia (ASDC) and L. Salotti (ASI), on behalf of the AGILE Team, 
report:

"SuperAGILE detected and localized a gamma ray burst 
on May 7th, at 07:45:00 UT. The event was detected during the
passage of the AGILE spacecraft through the South Atlantic 
Anomaly and this caused the non-detection by the automatic
burst search procedures, and the delayed identification thereof.
The observed duration in the 20-60 keV energy range is about 40 seconds, 
with a multi-peaked structure.
The burst position was reconstructed as (RA, Dec) (233.721 deg, 
56.424 deg), which is:

RA(J2000) = 15h 34m 53.11s
Dec(J2000) = 56d 25' 27.3"

with an uncertainty of 3' radius. The given uncertainty accounts 
for both the statistical and systematic errors. 

This position lies approximately 100 arcsec from the galaxy NGC 5969.

The telemetry of the AGILE Gamma Ray Imager (GRID) is disabled 
during the passage through the South Atlantic Anomaly, thus no
GRID data are available for this GRB."

This message may be cited.


GRB_name: GRB080506A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7698
SUBJECT: GRB 080506: VLA radio upper limit
DATE:    08/05/08 17:28:11 GMT
FROM:    Poonam Chandra at U Virginia/NRAO  <pc8s@virginia.edu>

Poonam Chandra (NRAO/UVA) and Dale A. Frail (NRAO) report on behalf
of the Caltech-NRAO-Carnegie GRB Collaboration:

"We used the Very Large Array to observe the field of view toward GRB
080506 (GCN 7685) at a frequency of 8.46 GHz at 2008 May 8.53 UT.
We do not detect the GRB afterglow at Swift-XRT position (GCN 7687).
The flux density at the afterglow position is -40 +/- 40 uJy.

The National Radio Astronomy Observatory is a facility of the National
Science Foundation operated under cooperative agreement by Associated
Universities, Inc."


GRB_name: GRB080507A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7699
SUBJECT: GRB 080507: Swift-XRT position of a possible afterglow
DATE:    08/05/08 18:25:00 GMT
FROM:    Vanessa Mangano at INAF-IASFPA  <vanessa@ifc.inaf.it>

V. Mangano, B. Sbarufatti (INAF-IASF PA), J. Kennea (PSU),
and W. H. Baumgartner (GSFC/UMBC)
report on behalf of the Swift-XRT team:

Swift started a ToO observation of GRB 080507 (Lapshov et al.,
GCN Circ. 7697) today at 14:05 UT.

We have analysed the first 2.5 ks of PC data and found a bright
uncatalogued source at RA, Dec = 233.68085, 56.43520
which is equivalent to:

RA (J2000):  15 34 43.40
Dec (J2000): +56 26 06.7

with an uncertainty of 2.5 arcsec (radius, 90% confidence;
astrometrically corrected X-ray position).
This is 90 arcsec from the SuperAGILE position.

We also found a second uncatalogued faint source at
RA, Dec = 233.662500, 56.420972 (118 arcsec from the
SuperAGILE position) and a third faint source at
RA, Dec =  233.612083, 56.428500  (217 arcsec from the
SuperAGILE potition), likely the counterpart of
SDSS J153426.68+562545.8.
At the moment data are not enough to say if these sources
are fading.

This is an official product of the Swift-XRT team


GRB_name: GRB080506A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7700
SUBJECT: GRB 080506:Optical observations from HCT
DATE:    08/05/08 19:41:11 GMT
FROM:    T.P. Prabhu at Indian Astro. Obs.  <tpp@crest.ernet.in>

D.K. Sahu, G.C. Anupama (IIA, Bangalore), Kuntal Misra (ARIES) report.

The field of GRB 080506 (Baumgartner et al., GCN 7685) was observed using
HFOSC mounted on the 2-m Himalayan Chandra Telescope, Indian Astronomical
Observatory, India. A series of 300sec exposures were taken in R-band
between  20:45 UT and 23:00 UT on 06/05/2008. The optical counter part is
detected in all our frames. Using the calibration by Kawabata et al.  (GCN
7686), the estimated R band magnitude of the optical counter part   is
20.13+/-0.1 mag at 20:47UT. The optical counter part faded by ~ 0.6 
magnitude during our  observations.

This message may be cited.


GRB_name: GRB080507A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7701
SUBJECT: GRB 080507: Optical Afterglow
DATE:    08/05/08 23:16:01 GMT
FROM:    Alexander Kann at TLS Tautenburg  <kann@tls-tautenburg.de>

D. A. Kann, C. Hoegner, S. Ertel and S. Schulze (TLS Tautenburg) report:

We observed the field of the AGILE GRB 080507 (Lapshov et al., GCN 7697) 
with the Tautenburg 1.34m Schmidt telescope after twilight in good 
conditions. We obtained 12 usable 180 second images in the Rc band, with a 
mid-exposure time of 1.54 days after the GRB.

At the position of the brightest X-ray source (Mangano et al., GCN 7699), 
we detect an optical source that is not visible in the DSS (but is 
significantly below the limiting magnitude) or the SDSS (which has a 
comparable limiting magnitude to our image). We consider this the optical 
afterglow of GRB 080507 due to the coincidence with the bright X-ray 
source. At the moment, we can't make any claims of variability.

Assuming the USNOB1.0 star just to the north of the afterglow position, at 
R.A. = 15 34 43.7, Dec. = +56 26 21, has R1 = 14.96 (R2 = 15.08), we find 
a magnitude for the afterglow of:

time (days) Rc dRc

1.5383  22.10 0.11

Further follow-up is encouraged to confirm a fading nature for this 
source.

We note that the error circle of the second faint X-ray source at R.A. = 
233.662500, Dec. = 56.420972 (Mangano et al., GCN 7699) also contains an 
optical source clearly visible in the SDSS and in our images, implying 
that this is a persistent source.

This message may be cited.


GRB_name: GRB080507A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7702
SUBJECT: GRB080507: Swift/UVOT followup observations
DATE:    08/05/09 14:02:51 GMT
FROM:    Alice Breeveld at MSSL-UCL  <aad@mssl.ucl.ac.uk>

A. A. Breeveld (MSSL/UCL) and W. H. Baumgartner (GSFC/UMBC)
on behalf of the Swift/UVOT team.

The Swift Ultra-Violet/Optical Telescope (UVOT) started a ToO 
observation of GRB 080507 (Lapshov et al., GCN Circ. 7697) 109312s 
after the AGILE trigger. At the position of the afterglow candidate 
seen in the Tautenburg telescope (Kann et al. GCN Circ. 7701), which 
also corresponds to the  brightest source in the Swift XRT (V. Mangano 
et al. GCN Circ. 7699), the UVOT has a very faint source that does not 
appear in DSS or SDSS. It is only detectable in summed white images, 
but does NOT appear to be fading.

The limiting magnitudes for the initial exposure and detections in 
summed images are as follows:

Filter         T_start(s)  T_stop(s)  Exp(s)  Mag

white         109312  109526  211.4     >21.3 (UL)
white         109312  111881  2462.3   22.6 +/- 0.4 (3 sig)
white 111881  116511  1355.3   22.1 +/- 0.3 (3.8 sig)

The values quoted above are in the UVOT photometric system
(Poole et al. 2008, MNRAS, 383, 627) and are not corrected for galactic 
reddening.


GRB_name: GRB080503A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7703
SUBJECT: GRB 080503: Hubble Space Telescope Imaging
DATE:    08/05/09 19:45:38 GMT
FROM:    Daniel Perley at U.C. Berkeley  <dperley@astro.berkeley.edu>

J. S. Bloom (UC Berkeley), W. Li (UC Berkeley), A. J. Levan (U. 
Warwick), D. A. Perley (UCB),  N. R. Tanvir (U. Leicester), N. R. Butler 
(UCB),  H-W. Chen (U. Chicago), R. Chornock (UCB), J. X. Prochaska 
(UCO/Lick), C. D. Bailyn (Yale), A. Bunker (U. Exeter), R. Chornock 
(UCB), B. Cobb (Yale), P. B. Hall (York U.), A. V. Filippenko (UCB), N. 
Gehrels (NASA/GSFC), K. Glazebrook (Swinburne), J. Granot (U. 
Hertfordshire), K. C. Hurley (UCB), D. Kocevski (UCB), B. Metzger (UCB), 
M. Modjaz (UCB), A. Miller (UCB), W. Lee (I. de Astronomia), S. Lopez 
(U. Chile), J. Norris (NASA/Ames), P. E. Nugent (LBNL), M. Pettini (U. 
Cambridge), D. Poznanski (UCB), A. L. Piro (UCB), E. Quataert (UCB), E. 
Ramirez-Ruiz (UCSC), J. Shiode (UCB), and T. Sakamoto (GSFC/UMBC) report:

Under Director's Discretionary Proposal (#11551), we acquired 
observations of GRB 080503 (Mao et al., GCN 7665) with the Hubble Space 
Telescope (HST+WFPC2), starting at 15:08 and lasting until 20:45 (UT 
2008-05-08), approximately 5.2 days after the GRB.  The total 
integration time was 2x1200s + 2x1100s (2 orbits) in F606W, 3x700s (1 
orbit) in F814W, and 3x700s (1 orbit) in F450W. The data were collected 
in a small dither pattern around the WFALL position to mitigate against 
CTE losses.

We clearly detect a point source at a location consistent with the 
optical transient (Perley et al., GCN 7678) in F606W, and marginally 
detect a source at this position in 450W.  The transient is not detected 
in F814W.  We report the following preliminary magnitudes:

F450W_AB = 26.95 +/- 0.27
F606W_AB = 26.86 +/- 0.15
F814W_AB > 26.6

The nearby source s1 (see Perley et al., GCN 7667) is also detected, and 
appears visibly extended, though this extension does not reach s2.  Two 
other faint, extended sources ("s3" and "s4") are detected about 1 
arcsecond to the northwest and southeast of the transient, respectively. 
  There is no obviously extended source detected at the position of s2.

The source is significantly fainter than observed in our Gemini 
measurements, which may suggest a break (as expected from an off-axis 
jet) or an exponential decline (as expected from an LP mini-supernova). 
  However, LP mini-SN models also predict a red late-time color, which 
is not observed.  We note also the detection of an X-ray afterglow in 
late-time Chandra observations (Butler et al., GCN in prep.)

An additional epoch of HST imaging will be obtained starting 15:05 
12-May-2008 UT.

An preliminary image with less-than-optimal cosmic ray reduction is 
posted to:
http://lyra.berkeley.edu/~dperley/080503/080503_hst660w_ep1.png

We are grateful to all the people STSCI that made such a rapid ToO possible.


GRB_name: GRB080503A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7704
SUBJECT: GRB 080503: Chandra Observation of X-ray Rebrightening or Flattening
DATE:    08/05/09 22:18:47 GMT
FROM:    Nat Butler at MIT/CSR  <nrbutler@space.mit.edu>

N. R. Butler (UC Berkeley), J. S. Bloom (UCB), W. Li (UCB), A. J. Levan (U.
Warwick), D. A. Perley (UCB),  N. R. Tanvir (U. Leicester), H-W. Chen (U.
Chicago), R. Chornock (UCB), J. X. Prochaska (UCO/Lick), C. D. Bailyn (Yale),
A. Bunker (U. Exeter), R. Chornock (UCB), B. Cobb (Yale), P. B. Hall
(York U.), A. V. Filippenko (UCB), N. Gehrels (NASA/GSFC), D. Burrows (PSU),
K. Glazebrook (Swinburne), J. Granot (U. Hertfordshire), K. C. Hurley (UCB),
D. Kocevski (UCB), B. Metzger (UCB), M. Modjaz (UCB), A. Miller (UCB), W.
Lee (I. de Astronomia), S. Lopez (U. Chile), J. Norris (NASA/Ames), P. E.
Nugent (LBNL), M. Pettini (U. Cambridge), D. Poznanski (UCB), A. L. Piro
(UCB), E. Quataert (UCB), E. Ramirez-Ruiz (UCSC), J. Shiode (UCB), and T.
Sakamoto (GSFC/UMBC) report:

From 2008/05/07 19:18:23 UT to 2008/05/08 04:09:59 UT (4.29 - 4.66 days post
burst), Chandra Director's Discretionary Time observations with ACIS-S were
conducted of the field of GRB 080503 (Mao et al. 2008; GCN7665) for a
total exposure of 29.8 ksec (livetime).  We find a highly significant
detection of one X-ray point source in the XRT error circle (Goad et al.
2008; GCN7669) at:

RA, Dec = 19:06:28.76, +68:47:35.3 +/- 0.5"  (J2000).

The source is 0.2" away from the Gemini optical source (S2) in Perley et al.
(2008; GCN7678), and is 0.7" away from the center of the XRT error circle.
The X-ray source is therefore highly likely to be associated with S2, which
is in turn highly likely to be associated with GRB 080503.  Astrometry is
established using Chandra field sources also detected in the Gemini images.

We detect 40+/-6 counts in the 0.5-8.0 keV band.  There is weak evidence
in favor of variability.  During the first half of the exposure, we measure
21+/-5 cts, as compared to 19+/-4 counts in the second half.  Testing
against the NULL hypothesis of a steady source, we find KS-prob=0.23.

The Chandra flux implies a flattening of the X-ray flux relative to
the rapid decay observed prior to ~13 ksec by the Swift XRT (Guidorzi et al.
2008; GCN7674).  We note also that XRT observations at late time (2.4-3.2
days post burst) exhibit a flux consistent with that of Chandra, yielding a
marginal (~1-sigma) XRT detection.

Minimizing the Cash (1976) statistic, we find the Chandra spectrum to
be acceptably fit by an absorbed powerlaw with photon index Gamma=1.5+/-0.5
and unabsorbed flux Fx(0.3-10 keV) = (1.5+/-0.7) x 10^(-14) erg/cm^2/s.  We
assume Galactic absorption only, as observed for the Swift XRT spectrum
(Guidorzi et al. 2008; GCN7674).

Roughly, the X-ray flux is consistent with an extrapolation of the optical
flux as observed by HST (Bloom et al. 2008; GCN7703), assuming the X-ray
spectral index.  If the optical flux is due to a a Li-Paczynski
"mini"-supernova (1998ApJ...507L..59L) as suggested by Perley et al. (2008;
GCN7678), then the X-ray light curve may be more easily explained by
invoking a separate emission mechanism.  Alternatively, both the optical
and X-ray fluxes may be due to shock energy re-injection or flaring 
occuring on timescales ~1-4 days post burst.

More detailed analyses are ongoing.

We thank Harvey Tananbaum, Patrick Slane, Andrea Prestwich, and the
rest of the Chandra observatory staff for their impressive rapid scheduling
and execution of this observation.

This message can be cited.


GRB_name: GRB080507A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7705
SUBJECT: GRB 080507: E Pur Si Muove!
DATE:    08/05/09 23:48:40 GMT
FROM:    Alexander Kann at TLS Tautenburg  <kann@tls-tautenburg.de>

D. A. Kann, C. Hoegner, R. Filgas and S. Klose (TLS Tautenburg) report:

We observed again the location of the candidate afterglow (Kann et al., 
GCN 7701) of the AGILE GRB 080507 (Lapshov et al., GCN 7697), which was 
also detected as a bright X-ray source (Mangano et al., GCN 7699). We 
obtained 20 x 180 sec images in the R band under excellent atmospheric 
conditions but with elevated sky background due to twilight and the waxing 
moon. The resulting stacked image is roughly half a magnitude deeper than 
the image from the first epoch (23.5 vs. 23, respectively).

We find that the candidate afterglow has significantly faded over the 
course of a day. Using the same comparison star as Kann et al. (GCN 7701), 
we find:

time (days) Rc dRc

2.5578  22.69 0.15

We also use SExtractor (Bertin & Arnouts 1996) to derive magnitudes, and 
find Rc = 21.95 +/- 0.14 and Rc = 22.65 +/- 0.20 in the first and second 
epoch, respectively, in accordance with our other results.

This fading behaviour is in contrast to the plateau phase or even rising 
behaviour reported from UVOT White images (Breeveld & Baumgartner, GCN 
7702), which may imply a non-monotonic light curve evolution.

With the clear detection of fading, we consider the identification of this 
source as the optical afterglow of GRB 080507 as secure.

Finally, we note that GRB 080507 was also detected by INTEGRAL SPI-ACS, 
showing a flat-topped structure, with possible multiple peaks, of 40 
seconds duration, in full agreement with the AGILE report (Lapshov et al., 
GCN 7697). The public light curve can be found here:

http://isdc.unige.ch/cgi-bin/cgiwrap/~beck/ibas/spiacs/ibas_acs_web.cgi/
?trigger=2008-05-07T07-44-58.8545-18523-00007-0

This message may be cited.


GRB_name: GRB080507A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7706
SUBJECT: GRB 080507: Keck photometry
DATE:    08/05/10 02:33:56 GMT
FROM:    Daniel Perley at U.C. Berkeley  <dperley@astro.berkeley.edu>

D. A. Perley (UC Berkeley), J. X. Prochaska (UCO/Lick), and J. Hennawi 
(UCB) report:

We imaged the field of Super-AGILE GRB 080507 (Lapshov et al., GCN 7697) 
with Keck I (+LRIS) during morning twilight starting at 15:03 UT on 
2008-05-08 (31.3 hours after the trigger).  Four exposures were taken in 
g and R filters simultaneously, although due to twilight only the first 
two R-band frames were usable.

We detect the optical afterglow reported by Kann et al. (GCN 7701) at a 
position of:

RA  =  15:34:43.39
Dec = +56:26:08.28
(estimated uncertainty of 0.7")

in R-band.  Our magnitude, calibrated to seven USNO-B1.0 stars, is R = 
22.20 +/- 0.11 at 1.31 days after the trigger.  This supports the 
generally non-fading behavior between 1-2 days after burst in 
observations from the Swift UVOT (Breeveld et al., GCN 7702) and 
Tautenberg (Kann et al.).

For reference, the observed magnitudes of two nearby USNO stars in the 
same calibration system are:

15:35:10.99 +56:23:57.02  R = 20.53 +/- 0.02
15:34:47.68 +56:25:16.44  R = 18.63 +/- 0.01


GRB_name: GRB080507A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7707
SUBJECT: GRB 080507: Swift XRT analysis confirms the X-ray afterglow
DATE:    08/05/11 06:48:03 GMT
FROM:    Valentina La Parola at INAF-IASPA  <laparola@ifc.inaf.it>

V. Mangano, B. Sbarufatti, V. LaParola, P. Romano (INAF-IASF PA)
and W. H. Baumgartner (GSFC/UMBC)
report on behalf of the Swift-XRT team:

Swift started a second ToO observation of GRB 080507 (Lapshov et al.,
GCN Circ. 7697) on May 9th at 17:24 UT.
We have analyzed the 4 ks PC observation, and found that the brightest
uncatalogued source detected during the previous ToO observation
(Mangano et al., GCN Circ. 7699) has decayed from a rate level of
(1.4 +/- 0.2) e-2 counts s-1 to a level of (2.2 +/- 0.7) e-3 counts s-1.
The second uncatalogued source in the SuperAGILE error circle is
still visible at the constant level of (3.0 +/- 1.0) e-3 counts s-1.

We can confirm that the brightest source detected in Mangano et al.,
GCN Circ. 7699 is the X-ray afterglow of GRB 080507, in agreement with 
the observation reported by Kann et al. (GCN 7705).


This is an official product of the Swift-XRT team


GRB_name: GRB080507A
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7708
SUBJECT: GRB 080507: Suzaku WAM observation of the prompt emission
DATE:    08/05/12 03:31:06 GMT
FROM:    Makoto Tashiro at Saitama U/Swift  <tashiro@phy.saitama-u.ac.jp>

T. Sugasahara, K. Onda, M. Tashiro, Y. Terada, Y. Urata, A. Endo,
N. Kodaka, K. Morigami, W. Iwakiri (Saitama U.),
M. Ohno, M. Kokubun, M. Suzuki, T. Takahashi (ISAS/JAXA),
K. Yamaoka, S. Sugita (Aoyama Gakuin U.), Y.E. Nakagawa,
T. Tamagawa (RIKEN), T. Uehara, T. Takahashi, Y. Fukazawa, C. Kira,
Y. Hanabata (Hiroshima U.), T. Enoto, K. Nakazawa,
K. Makishima (Univ. of Tokyo), E. Sonoda, M. Yamauchi, H. Tanaka,
R. Hara (Univ. of Miyazaki), , S. Hong (Nihon U.),
on behalf of the Suzaku WAM team, report:

The long GRB 080507 (SuperAGILE: Lapshov et al., GCN 7697)
triggered the Suzaku Wide-band  All-sky Monitor (WAM) which covers
an energy range of 50 keV - 5 MeV at 07:45:00 UT (=T0). The
observed light curve shows a multi-peaked structure starting at T0,
ending at T0+45s, with a duration (T90) of about 30 seconds.
The fluence in 100 - 1000 keV was 4.1(+0.1,-0.3)*10^-5 erg/cm^2.
The 1-s peak flux measured from T0+2s was 3.5(+0.2,-1.3) photons/cm^2/s
in the same energy range.

A preliminary result shows that the time-averaged spectrum from
T0 to T0+45s is well fitted by a power-law with exponential cutoff model:
   dN/dE ~  E^{-alpha} * exp(-(2-alpha)*E/Epeak) with
   alpha       0.79(+0.26, -0.28), and
   Epeak       492(+70, -49) keV (chi^2/d.o.f. = 15.9/23).

All the quoted errors are at statistical 90% confidence level,
in which the systematic uncertainties are not included.

The light curves for this burst are available at:
http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html


GRB_name: GRB080506A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7709
SUBJECT: GRB 080506: NAYUTA Optical Observation
DATE:    08/05/12 14:19:21 GMT
FROM:    Ryo Iizuka at NHAO  <iizuka@nhao.go.jp>

S. Maeno, H. Naito, S. Narusawa and R. Iizuka report on behalf of NHAO.

We observed the field of GRB 080506 (GCN 7685) with MINT on the
2.0-m NAYUTA telescope at Nishi-Harima Astronomical Observatory,
Japan. We detected the optical afterglow in R-band on 2008 May 6
17:58:02 UT  (701 seconds after the BAT trigger).

The magnitudes relative to the USNO B1.0 catalog are below.

Start(UT) exp(sec) R-mag R-err
--------------------------------------------
02:58:02    150    18.23    0.11
03:03:51    240    18.22    0.12
03:14:22    300    18.51    0.13
03:32:29    300    18.95    0.13
03:53:52    450    19.26    0.13
04:10:55    450    19.64    0.21
--------------------------------------------


GRB_name: GRB080319B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7710
SUBJECT: GRB 080319B: Further HST observations and underlying host
DATE:    08/05/12 18:35:30 GMT
FROM:    Andrew Levan at U.of Leicester  <anl@star.le.ac.uk>

A.J. Levan (U. Warwick), N.R. Tanvir (U. Leicester), A.S. Fruchter (STScI) 
and J. Graham (STScI) report:

We have obtained a second epoch of HST observations of GRB 080319B on 11 
May 2008. 2 orbits (3200s) of observations were taken in the F606W and 
F814W filters. The afterglow has clearly faded from our first epoch of 
observations and a faint host galaxy is now visible at the afterglow 
location. We measure magnitudes for the combined (afterglow+host) source 
of;

F606W(AB)=26.3 +/ -0.1
F814W(AB)=25.9 +/ -0.1

Relative astrometry between the two epochs of HST observations suggests 
that the afterglow is marginally (0.1 +/- 0.05 arcseconds) offset from the 
centroid of the host galaxy in the F606W image. This implies that the 
afterglow may not be the dominant source of light at the current epoch, 
and is likely significantly fainter than the magnitudes quoted above.


GRB_name: GRB080507A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7711
SUBJECT: Konus-Wind observation of GRB 080507
DATE:    08/05/13 16:04:13 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val@mail.ioffe.ru>

S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks,
and T. Cline on behalf of the Konus-Wind team report:

The long GRB 080507 localized by SuperAGILE (Lapshov et al., GCN
7697) triggered Konus-Wind at T0=27902.194 s UT (07:45:02.194).

As observed by Konus-Wind the burst
had a fluence of 5.09(-0.24, +0.26)x10^-5 erg/cm2,
and a 256-ms peak flux measured from T0+4.960 s
of (3.07 +/- 0.44)x10^-6 erg/cm2/s
(both in the 20 keV - 2 MeV energy range).

The time-integrated spectrum of the burst
(from T0 to T0+47.616 s) is well fitted (in the 20 keV-2 MeV range)
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with alpha = -0.88 +/- 0.06,
and Ep = 423(-33, +38) keV (chi2 = 55.0/61 dof).
Fitting by GRBM (Band) model yields:
the low-energy photon index is alpha = -0.85 +/- 0.07,
the high energy photon index beta < -2.34,
the peak energy Ep =  399(-32, +42) keV (chi2 = 54.6/60 dof).

All the quoted errors are at the 90% confidence level.

The Konus-Wind light curve of this GRB is available
at http://www.ioffe.rssi.ru/LEA/GRBs/GRB080507_T27902/


GRB_name: GRB080514A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7712
SUBJECT: GRB080514: REM NIR & Optical Observations
DATE:    08/05/14 10:56:04 GMT
FROM:    Stefano Covino at Brera Astronomical Observatory  <stefano.covino@brera.inaf.it>

S. Covino, P. D'Avanzo, D. Fugazza, L.A. Antonelli, L.  Calzoletti,   
S. Campana, G.  Chincarini, M.L. Conciatore, S. Cutini, V. D'Elia,  
F.  D'Alessio, F.  Fiore, P. Goldoni, D. Guetta,  C. Guidorzi, G.L.   
Israel, E. Maiorano, N. Masetti, A. Melandri, E. Meurs, L. Nicastro,   
E. Palazzi, E. Pian, S. Piranomonte, L.  Stella, G.  Stratta, G.
Tagliaferri, G. Tosti, V.Testa, S.D. Vergani,  F. Vitali report on   
behalf of the REM team:

The robotic 60-cm REM telescope located at La Silla (Chile) observed   
automatically the field of the GRB 080514 on April 14 10:34:14 UT.

No new source is visible in the XRT error circle down to the 2MASS  
limits, although the presence of a bright source already present in  
the 2MASS catalogue (H~9) and well within the XRT error circle makes  
the photometry less reliable.


Further analyses and observations are in progress.


GRB_name: GRB080514B
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7715
SUBJECT: GRB 080514B: SuperAGILE/IPN GRB Localization
DATE:    08/05/14 19:06:44 GMT
FROM:    Marco Feroci at IASF/INAF  <feroci@iasf-roma.inaf.it>

M. Rapisarda, E. Costa, E. Del Monte, I. Donnarumma, Y. Evangelista, 
M. Feroci, I. Lapshov, F. Lazzarotto, L. Pacciani, P. Soffitta, 
(INAF/IASF Rome), A. Giuliani, S. Vercellone, A. Chen, S. Mereghetti, A. 
Pellizzoni, F. Perotti, F. Fornari, M. Fiorini, P. Caraveo
(INAF/IASF Milan), A. Bulgarelli, F. Gianotti, M. Trifoglio, 
G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, 
M. Galli, (INAF/IASF Bologna), M. Tavani, G. Pucella, F. D'Ammando, V. 
Vittorini, A. Argan, A. Trois (INAF/IASF Rome), G. Barbiellini, 
F. Longo (INFN Trieste), P. Cattaneo (INFN Pavia), P. Picozza, 
A. Morselli (INFN Roma-2), M. Prest, E. Vallazza (Universita' 
dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), and  P. Giommi, C. 
Pittori, B. Preger, F. Verrecchia (ASDC) and L. Salotti (ASI), 
on behalf of the AGILE Team, 

K. Hurley, 
on behalf of the Mars Odyssey team,

I. G. Mitrofanov, D. Golovin, M. L. Litvak, and A. B. Sanin,
on behalf of the HEND-Odyssey GRB team, and

W. Boynton, C. Fellows, K. Harshman, C. Shinohara and R. Starr, on
behalf of the GRS-Odyssey GRB team,

report:

"SuperAGILE and AGILE/MCAL detected a gamma ray burst on 
May 14th, at 09:55:56 UT. The event was localized by SuperAGILE
at approximately 38 degrees off axis, in the one-dimensional portion of 
its field of view, thus providing a narrow and long error box. 
The narrow side is 6 arcmin wide, while the long side is approximately 40 
degrees wide. In the 20-60 keV energy range the event had a 10s duration, 
with a multi-peaked structure.

The same event was also detected by Mars Odyssey. The IPN was 
thus able to reduce the SuperAGILE error box to the 100 sq arcmin 
error box whose corners are given by the following 
coordinates (RA, Dec):

  322.962 (21h 31m 50.81s)       0.733  (0d 43m 59.69s)
  322.774 (21h 31m  5.74s)       0.667  (0d 40m  2.78s)
  322.867 (21h 31m 27.99s)       0.806  (0d 48m 21.16s)
  322.678 (21h 30m 42.80s)       0.740  (0d 44m 23.63s)

The centroid of the error box is at (RA, Dec)= (322.820, 0.737)
and the maximal distance between the box corners is 0.283 deg, 
that is 16.9 arcmin.

The event occurred in the field of view of the AGILE GRID.
A report on the AGILE/GRID data analysis will follow shortly.

We urge follow-up observations at all wavelengths."

This message may be cited.


GRB_name: GRB080514B
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7716
SUBJECT: GRB 080514B: possible AGILE detection at E>50 MeV
DATE:    08/05/14 19:13:06 GMT
FROM:    Sandro Mereghetti at IASF/CNR  <sandro@iasf-milano.inaf.it>

A. Giuliani, F. Fornari, S. Mereghetti, S. Vercellone, A. Chen, A. 
Pellizzoni, F. Perotti, M. Fiorini, P. Caraveo, A. Zambra (INAF/IASF 
Milan), P. Soffitta, I. Donnarumma, E. Del Monte, M. Feroci, Y. 
Evangelista, E. Costa, I. Lapshov, F. Lazzarotto, L. Pacciani, M. 
Rapisarda (INAF/IASF Rome), A. Bulgarelli, F. Gianotti, M. Trifoglio, G. 
Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli, (INAF/IASF 
Bologna), M. Tavani, G. Pucella, F. D'Ammando, V. Vittorini, A. Argan, A. 
Trois (INAF/IASF Rome), G. Barbiellini, F. Longo (INFN Trieste), G. De 
Paris, P. Picozza, A. Morselli (INFN Roma-2), M. Prest, E. Vallazza 
(Universita' dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), and P. 
Giommi, C. Pittori, (ASDC) and L. Salotti (ASI), on behalf of the AGILE 
Team, report:


"A quick look analysis of the AGILE GRID data of GRB 080514B (Rapisarda et 
al. GCN 7715) shows a possible detection at energies E>50 MeV at a 
position consistent with the SuperAGILE-IPN localization.

We have requested a ToO observation of the SuperAGILE-IPN error box with 
the Swift satellite. We encourage follow-up observations at other 
wavelengths."

This message may be cited.


GRB_name: GRB080430A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7717
SUBJECT: GRB 080430
DATE:    08/05/14 21:48:32 GMT
FROM:    Joel Nicolas at none  <joel.nicolas@wanadoo.fr>

J.Nicolas reports:

Visible Obervation afterglow radiation of the start gamma GRB080430
TEL 0.28-m F/6.5 reflector
Observatory:Vallauris 07:30:49 E 43:34:40 N B51

Composite of 26 images of 90s without filter
Photometry at magnitude 19
Date 08/04/30 22h15 UT

Using the USNO-A2 catalog, the source is located at:
RA (J200O)  = 11h 01m 14.76s
DEC (J2000) = +51d 41' 08.46"

The Image can be found at
http://astrosurf.com/jnicolas/sursaut_gamma.htm


GRB_name: GRB080514B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7718
SUBJECT: GRB 080514B: Watcher observations
DATE:    08/05/15 04:33:22 GMT
FROM:    Antonio Deugarte at IAA-CSIC  <deugarte@iaa.es>

P. Kubanek (IAA-CSIC, GACE), J. French (UCD),
A. de Ugarte Postigo (ESO) report  on behalf of a larger
collaboration:

The 0.4m WATCHER telescope located at Boyden Observatory,
South Africa, has observed the field of GRB 080514B (Rapisarda
et al., GCN 7715) starting at May 15.042 UT (~15.1 hours after
the burst) in a sequence of 120s R band exposures. A combined
image covering ~90% of the error box does not show any new
source down to a limiting magnitude of R>19 at a mean epoch of
May 15.076 UT.

Further analysis is ongoing.


GRB_name: GRB080514B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7719
SUBJECT: GRB 080514B: Afterglow candidate
DATE:    08/05/15 05:40:09 GMT
FROM:    Antonio Deugarte at IAA-CSIC  <deugarte@iaa.es>

A de Ugarte Postigo (ESO), A. Castro-Tirado,
J. Gorosabel, M. Jelinek (IAA-CSIC), P. Kubanek
(IAA-CSIC, GACE) A. Garcia,  A. Pimienta,
E. Curras (IAC), C. Pereira (Armagh Obs.), on behalf
of a larger collaboration report:

We have observed the error box of GRB080514B (Rapisarda et
al., GCN 7715) from the 0.8m IAC80 telescope at Izaa Observatory
(Spain) in I-band starting on May 15.133 (17.3 hours after the burst)
There is a source with a mag of I~20.4, not present in the SDSS-i at
the following coordinates (J2000 +/-1"):
R.A.: 21:31:22.69
Dec.: +00:42:28.9

Further observations are encouraged to confirm if this is related to
the GRB.


GRB_name: GRB080514B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7720
SUBJECT: GRB 080514B: Finding chart
DATE:    08/05/15 06:14:48 GMT
FROM:    Antonio Deugarte at IAA-CSIC  <deugarte@iaa.es>

A de Ugarte Postigo (ESO), A. Castro-Tirado,
J. Gorosabel, M. Jelinek (IAA-CSIC), P. Kubanek
(IAA-CSIC, GACE) A. Garca,  A. Pimienta,
E. Curras (IAC), C. Pereira (Armagh Obs.), on behalf
of a larger collaboration report:

A finding chart of the optical candidate of GRB 080514B
(Rapisarda et al., GCN 7715) reported in GCN 7719,
compared to the SDSS-i frame can be found at:
http://www.sc.eso.org/~adeugart/GRB/080514B/GRB080514B.jpg


GRB_name: GRB080515A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7721
SUBJECT: GRB 080515: Swift detection of a burst
DATE:    08/05/15 06:19:28 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

S. T. Holland (CRESST/USRA/GSFC), A. P. Beardmore (U Leicester),
P. A. Evans (U Leicester), E. A. Hoversten (PSU),
H. A. Krimm (CRESST/GSFC/USRA), C. B. Markwardt (CRESST/GSFC/UMD),
P. T. O'Brien (U Leicester), K. L. Page (U Leicester),
D. M. Palmer (LANL) and R. L. C. Starling (U Leicester) report on
behalf of the Swift Team:

At 06:01:13 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 080515 (trigger=311658).  Swift could not slew to the burst
due to Sun constraint.  The BAT on-board calculated location is 
RA, Dec 3.150, +32.599 which is 
   RA(J2000) = 00h 12m 36s
   Dec(J2000) = +32d 35' 57"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve from TDRSS was 
truncated by the beginning of a Malindi downlink and
is further complicated as we were coming out of the SAA at the time, but
shows activity from the trigger time to the end of available data
at T+8s, with a peak count rate of ~500 counts/s (15-350 keV). 

This burst is only 45.9 degrees from the Sun, so there will be no prompt 
XRT or UVOT data. The field will be outside the Swift Sun observing 
constraint tomorrow. 

Burst Advocate for this burst is S. T. Holland (sholland AT milkyway.gsfc.nasa.gov). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB080514B
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7722
SUBJECT: GRB 080514B, GROND observations
DATE:    08/05/15 07:59:26 GMT
FROM:    Sylvio Klose at TLS Tautenburg  <klose@tls-tautenburg.de>

A. Rossi (Tautenburg), A. Kupcu-Yoldas, J. Greiner (MPE Garching), 
S. Klose, R. Filgas (Tautenburg), A. Yoldas, T. Kruehler (MPE), and 
G. Szokoly (Eoetvoes Univ. Budapest and MPE) 
report on behalf of the GROND team:


We observed the field of GRB 080514B (Rapisarda et al., GCN 7715; Giuliani 
et al., GCN 7716) simultaneously in g'r'i'z'JHK using the multi-channel 
imager GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2m 
MPI/ESO telescope on La Silla (Chile). Observations started at 7:03 UT, 
about 21 h after the burst.

The afterglow candidate reported by de Ugarte Postigo et al. (GCN 7719) is 
detected in g'r'i'z'. Preliminary photometry yields g' = 19.95 +/- 0.2, 
calibrated against NOMAD field stars. Observations are ongoing.

We thank Antonio de Ugarte Postigo (ESO) for a rapid communication of the
finding chart.


GRB_name: GRB080514B
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7723
SUBJECT: GRB 080514B: Swift-XRT analysis
DATE:    08/05/15 08:19:04 GMT
FROM:    Kim Page at U.of Leicester  <kpa@star.le.ac.uk>

K.L. Page, A.P. Beardmore (U. Leicester), S. Mereghetti (INAF - IASF 
Milano), M. Feroci and M. Tavani (INAF/IASF Roma) report on behalf of the 
Swift-XRT and AGILE teams:

Following a ToO request, Swift-XRT started observing the field of GRB 
080514B at 20:12 on 14th May, about 37 ks after the trigger. Within the 
SuperAGILE/IPN error box, there are two sources detected, one of which is 
much brighter and appears to be fading. We therefore believe this to be 
the X-ray afterglow of the GRB.

Using 925 s of overlapping XRT Photon Counting mode and UVOT data, we find 
an astrometrically corrected X-ray position (using the XRT-UVOT alignment 
and matching UVOT field sources to the USNO-B1 catalogue): RA, Dec = 
322.84426, 0.70843 which is equivalent to:

RA (J2000):   21 31 22.62
Dec (J2000): +00 42 30.3

with an uncertainty of 1.6 arcsec (radius, 90% confidence). This position 
is 1.7 arcsec from the i-filter object mentioned by de Ugarte Postigo et 
al., in GCN Circ. 7719.

A spectrum of the three orbits of Photon Counting (PC) mode data (6 ks of 
data, spanning 37-49 ks after the trigger) can be modelled with an 
absorbed power-law of Gamma = 2.06 +0.35/-0.31 and NH = (1.2 
+0.8/-0.6)x10^21 cm^-2, which is slightly in excess of the Galactic value 
of 3.75x10^20 cm^-2. The observed (unabsorbed) 0.3-10 keV flux is 
2.34x10^-12 (3.14x10^-12) erg cm^-2 s^-1. This corresponds to an observed 
counts to flux conversion of 1 count = 3.96x10^-11 erg cm^-2.

The light-curve can be fitted with a single power-law, with a slope of 
alpha = 1.5 +/- 1.0. If the light-curve continues to follow this decay, 
the count rate at 48 hours is predicted to be 6.6x10^-3 count s^-1 (an 
observed flux of 2.6x10^-13 erg cm^-2 s^-1).

This circular is an official product of the Swift-XRT team.


GRB_name: GRB080514B
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7724
SUBJECT: GRB 080514B: slow fading behaviour ?
DATE:    08/05/15 09:35:14 GMT
FROM:    Aybuke, Kupcu Yoldas at MPE  <ayoldas@mpe.mpg.de>

A. Rossi (Tautenburg), A. Kupcu-Yoldas, J. Greiner (MPE Garching),
S. Klose, R. Filgas (Tautenburg), A. Yoldas, T. Kruehler (MPE), and
G. Szokoly (Eoetvoes Univ. Budapest and MPE)
report on behalf of the GROND team:

We continued observing the field of GRB 080514B (Rapisarda et al.,  
GCN 7715; Giuliani
et al., GCN 7716) simultaneously in g'r'i'z'JHK using the multi-channel
imager GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2m
MPI/ESO telescope on La Silla (Chile).

We detect a very slow fading behaviour in the afterglow brightness.
The i' band magnitude dropped ~0.05 magnitudes within 1.5 hours,  
resulting in i'~20.9 around 08:20 UT. This magnitude is ~0.5  
magnitudes fainter than the i-band magnitude given by Ugarte et al.  
(GCN 7719).

Please note that the g' magnitude mentioned in GCN 7722 has a typo;  
it should be g' = 21.2.


GRB_name: GRB080514B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7725
SUBJECT: GRB 080514B: KPNO 4m IR observations
DATE:    08/05/15 11:32:00 GMT
FROM:    Adria C. Updike at Clemson U  <aupdike@clemson.edu>

Adria C. Updike, Ginger Bryngelson, and Dieter H. Hartmann (Clemson
University) report on behalf of the Clemson GRB Follow-Up Team:

We observed GRB 080514B (Hurley et al., GCN 7715) using the KPNO 4m
telescope and the NEWFIRM NIR imager under decent weather conditions.  In
4 min of stacked exposures beginning 24 hours and 20 minutes after the
trigger, we detect the afterglow (Postigo et al., GCN 7719) at J = 19.8
+/- 0.2 (as calibrated to the 2MASS catalog).  Observations are ongoing.

This message may be cited.


GRB_name: GRB080515A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7726
SUBJECT: GRB 080515, Swift-BAT refined analysis
DATE:    08/05/15 13:44:19 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

E. Fenimore (LANL), S. D. Barthelmy (GSFC), W. Baumgartner (GSFC/UMBC),
J. Cummings (GSFC/UMBC), N. Gehrels (GSFC), S. T. Holland (CRESST/USRA/GSFC),
H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), K. McLean (GSFC/UMD),
D. Palmer (LANL), T. Sakamoto (GSFC/UMBC), G. Sato (GSFC/ISAS),
M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-237 to T+962 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 080515 (trigger #311658)
(Holland, et al., GCN Circ. 7721).  The BAT ground-calculated position is
RA, Dec = 3.166, 32.564 deg, which is 
   RA(J2000)  =  00h 12m 39.8s 
   Dec(J2000) = +32d 33' 49.9" 
with an uncertainty of 1.6 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 8%.
 
The mask-weighted light curve shows a single peak starting at ~T-5 sec,
peaking at ~T+2 sec, and ending at ~T+25 sec.
T90 (15-350 keV) is 21 +- 5 sec (estimated error including systematics).
 
The time-averaged spectrum from T-2.6 to T+24.0 sec is best fit by a power law
with an exponential cutoff.  This fit gives a photon index 0.94 +- 1.21, 
and Epeak of 25.0 +- 15.6 keV (chi squared 47.2 for 56 d.o.f.).  For this
model the total fluence in the 15-150 keV band is 2.0 +- 0.3 x 10^-6 erg/cm2
and the 1-sec peak flux measured from T+1.37 sec in the 15-150 keV band is
3.9 +- 0.7 ph/cm2/sec.  A fit to a simple power law gives a photon index
of 2.44 +- 0.19 (chi squared 53.8 for 57 d.o.f.).  All the quoted errors
are at the 90% confidence level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/311658/BA/
 
We also note that the fluence ratio in a simple power-law fit between the
25-50 keV band and the 50-100 keV band is 1.35.  This fluence ratio is larger
than 1.32 which can be achieved in the Band function of alpha=-1.0, beta=-2.5,
and Epeak=30 keV.  Thus, preliminary analysis shows that Epeak of the burst
is very likely around or below 30 keV.  Therefore the burst can be classified
as an X-ray flash (e.g. Sakamoto et al. ApJ in press, arXiv:0801.4319).


GRB_name: GRB080513A
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7728
SUBJECT: IPN triangulation of bright GRB 080513
DATE:    08/05/15 15:39:38 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val@mail.ioffe.ru>

S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks
on behalf of the Konus-Wind team,

K. Hurley and T. Cline on behalf of the Mars Odyssey, Konus,
and MESSENGER GRB teams,

W. Boynton, C. Fellows, K. Harshman, C. Shinohara and R. Starr, on
behalf of the GRS-Odyssey GRB team,

I. G. Mitrofanov, D. Golovin, M. L. Litvak, and A. B. Sanin,
on behalf of the HEND-Odyssey GRB team,

J. Cummings, S. Barthelmy, N. Gehrels, and H. Krimm, on behalf of
the Swift-BAT team,

A. von Kienlin, G. Lichti, and A. Rau, on behalf of the
INTEGRAL SPI-ACS GRB team, report:

Mars Odyssey, Konus-Wind, Swift-BAT, and INTEGRAL-SPI-ACS
observed the long-duration bright GRB 080513 at about 18850 s UT 
(05:14:10). The burst was outside the coded field of view of the BAT. 
The burst light curve shows a multipeaked structure with a duration of 
~30 sec, followed by a weak pulse at ~T0+70 sec.

We have triangulated the burst to the following, preliminary 3-sigma
error box:
-----------------------------------------------
       RA(2000)                    Dec(2000)
-----------------------------------------------
Center:
  163.283 (10h 53m 08s)   +28.195 (+28d 11' 43")
Corners:
  163.291 (10h 53m 10s)   +28.731 (+28d 43' 51")
  163.334 (10h 53m 20s)   +27.777 (+27d 46' 36")
  163.268 (10h 53m 04s)   +27.646 (+27d 38' 47")
  163.227 (10h 52m 55s)   +28.606 (+28d 36' 21")
-------------------------------------------------

The error box area is 213 sq. arcmin and
the maximal distance between the box corners is 1.09 deg.
This error box may be improved.

Preliminary analysis of the Konus-Wind data yields
a burst fluence of ~2x10^-5 erg/cm2 (in the 20 keV - 2 MeV range),
and an Epeak of the time-integrated spectrum of ~200 keV.

Detailed spectral parameters will be reported later.


GRB_name: GRB080513A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7729
SUBJECT: Konus-Wind observation of GRB 080513
DATE:    08/05/15 16:02:44 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val@mail.ioffe.ru>

S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks,
and T. Cline on behalf of the Konus-Wind team report:

The long GRB 080513 localized by IPN (Golenetskii et al., GCN 7728)
triggered Konus-Wind at T0=18849.927 s UT (05:14:09.927).

As observed by Konus-Wind the burst
had a fluence of 2.02(-0.17, +0.20)x10^-5 erg/cm2,
and a 16-ms peak flux measured from T0+24.016 s
of (1.15 +/- 0.30)x10^-5 erg/cm2/s
(both in the 20 keV - 2 MeV energy range).

The time-integrated spectrum of the burst
(from T0 to T0+32.256 s) can be fitted (in the 20 keV-2 MeV range)
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with alpha = -1.48(-0.13, +0.12)
and Ep = 223(-38, +62) keV (chi2 = 76.6/61 dof).
Fitting by GRBM (Band) model yields the same alpha and Ep,
and only an upper limit on the high energy photon index: beta < -2.19
(chi2 = 76.0/60 dof).

The spectrum of the most intense part (from T0+16.640 to T0+24.064 s)
is well fitted (in the same range)
by a power law with exponential cutoff model
with alpha =  -1.31(-0.12, +0.11)
and Ep = 317(-50, +73) keV (chi2 = 56.7/61 dof).
Fitting by GRBM (Band) model yields the same alpha and Ep,
and only an upper limit on the high energy photon index: beta < -2.20
(chi2 = 56.5/60 dof).
The fluence of this part is (1.18 +/- 0.10)x10^-5 erg/cm2
(in the 20 keV - 2 MeV energy range).

All the quoted errors are at the 90% confidence level.

The Konus-Wind light curve of this GRB is available
at http://www.ioffe.rssi.ru/LEA/GRBs/GRB080513_T18849/

[GCN OPS NOTE(15may08): Per author's request, "080515" in the first line
was chanegd to "080513".]


GRB_name: GRB080514B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7730
SUBJECT: GRB 080514B : redshift estimation
DATE:    08/05/15 16:24:56 GMT
FROM:    Bruce Gendre at LAM-OAMP  <bruce.gendre@oamp.fr>

B. Gendre (LAM/CNRS/Universite de Provence), A. Galli (IASF-Roma/INAF), 
M. Bor (OHP/CNRS) report :

Using the XRT analysis reported by Page et al. (GCN 7723), we 
extrapolated an X-ray flux of 4.8 10^-13 cgi 1 day after the burst (2-10 
keV). Using the Boer & Gendre relation, we estimate the redshift of GRB 
080514B to be either 2.8 or 0.9 if this event is a group I or II 
respectively (see Gendre, Galli & Bor, ApJ, in press), with 
uncertainties of 30%. Further constraints on the redshift could be set 
by B observations of the afterglow candidate reported in de Ugarte 
Postigo et al. (GCN 7719).

This message can be cited.


GRB_name: GRB080705A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7731
SUBJECT: VLA upper limit on GRB 080705
DATE:    08/05/15 17:28:28 GMT
FROM:    Poonam Chandra at U Virginia/NRAO  <pc8s@virginia.edu>

Poonam Chandra (NRAO/UVA) and Dale A. Frail (NRAO) report on behalf
of the Caltech-NRAO-Carnegie GRB Collaboration:

"We used the Very Large Array to observe the field of view toward 
super-AGILE GRB 080507 (GCN 7697) at a frequency of 8.46 GHz at 2008 May 13.14 UT.
We do not detect the GRB afterglow at Swift-XRT position (GCN 7699).
The flux density at the afterglow position is 44  49 uJy.

The National Radio Astronomy Observatory is a facility of the National
Science Foundation operated under cooperative agreement by Associated
Universities, Inc."


GRB_name: GRB080507A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7732
SUBJECT: Errartum: VLA upper limit on GRB 080507
DATE:    08/05/15 17:37:17 GMT
FROM:    Poonam Chandra at U Virginia/NRAO  <pc8s@virginia.edu>

Sorry. GCN 7731 is about GRN 080507, and not 080705.
Poonam

TITLE:   GCN CIRCULAR
NUMBER:  7731
SUBJECT: VLA upper limit on GRB 080705
DATE:    08/05/15 17:28:28 GMT
FROM:    Poonam Chandra at U Virginia/NRAO  <pc8s@virginia.edu>

Poonam Chandra (NRAO/UVA) and Dale A. Frail (NRAO) report on behalf
of the Caltech-NRAO-Carnegie GRB Collaboration:

"We used the Very Large Array to observe the field of view toward 
super-AGILE GRB 080507 (GCN 7697) at a frequency of 8.46 GHz at 2008 May 13.14 UT.
We do not detect the GRB afterglow at Swift-XRT position (GCN 7699).
The flux density at the afterglow position is 44  49 uJy.

The National Radio Astronomy Observatory is a facility of the National
Science Foundation operated under cooperative agreement by Associated
Universities, Inc."


GRB_name: GRB080516A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7733
SUBJECT: GRB 080516: Swift detection of a burst
DATE:    08/05/16 00:47:29 GMT
FROM:    David Burrows at PSU/Swift  <dxb15@psu.edu>

S. T. Holland (CRESST/USRA/GSFC), S. D. Barthelmy (GSFC),
D. N. Burrows (PSU), E. A. Hoversten (PSU), J. A. Kennea (PSU),
H. A. Krimm (CRESST/GSFC/USRA), F. E. Marshall (NASA/GSFC),
K. L. Page (U Leicester), D. M. Palmer (LANL),
M. Stamatikos (NASA/ORAU), R. L. C. Starling (U Leicester) and
E. Troja (U Leicester/INAF-IASFPA) report on behalf of the Swift
Team:

At 00:17:07 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 080516 (trigger=311762).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 120.629, -26.176 which is 
   RA(J2000) = 08h 02m 31s
   Dec(J2000) = -26d 10' 33"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a multi-peaked
structure with a duration of about 20 sec.  The peak count rate
was ~2500 counts/sec (15-350 keV), at ~0 sec after the trigger. 

The XRT began observing the field at 00:18:29.9 UT, 82.9 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued
X-ray source with an enhanced position: RA, Dec 120.64234, -26.15900
which is equivalent to:
   RA(J2000)  = 08h 02m 34.16s
   Dec(J2000) = -26d 09' 32.4"
with an uncertainty of 3.7 arcseconds (radius, 90% containment). This is
75 arcsec from the BAT position, within the BAT error circle. 

UVOT took a finding chart exposure of nominal 400 seconds with the V 
filter  starting 81 seconds after the BAT trigger. No afterglow 
candidate has been  found in the initial data products. This is a 
particularly crowded field with many stars.  The 8'x8' region for 
the list of sources  generated on-board covers  100% of the XRT 
error circle. The limiting  magnitude is about  17.7. No correction has
been made  for the large, but uncertain extinction  expected. 

Burst Advocate for this burst is S. T. Holland (sholland AT milkyway.gsfc.nasa.gov). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB080514B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7734
SUBJECT: GRB 080514B: NOT observations
DATE:    08/05/16 06:06:27 GMT
FROM:    Daniele Malesani at Niels Bohr Inst,Dark Cosmology Center  <malesani@astro.ku.dk>

D. Malesani (DARK/NBI), P.E. Nissen (Univ. Aarhus), W.J. Schuster 
(UNAM), and J.P.U. Fynbo (DARK/NBI), report on behalf of a larger 
collaboration:

We observed the afterglow of GRB 080514B (Rapisarda et al., GCN 7715; 
Giuliani et al., GCN 7716; de Ugarte Postigo et al., GCN 7719) with the 
NOT equipped with ALFOSC. Observations were carried out with the B, R 
and I filters.

We clearly detect the afterglow in all bands. On mean time May 16.184 UT 
(1.77 days after the trigger), we measure R = 22.52 +- 0.10 (AB), 
calibrated against SDSS r magnitudes. The detection in B implies a 
redshift limit z < 3.7.


GRB_name: GRB080516A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7735
SUBJECT: GRB 080516: Enhanced Swift-XRT position
DATE:    08/05/16 07:56:46 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

A.P. Beardmore, P.A. Evans, M.R. Goad J.P. Osborne (U. Leicester)
report on behalf of the Swift-XRT team.

Using 799 s of overlapping XRT Photon Counting mode and UVOT
data for GRB 080516, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 120.64196, -26.15962 which is
equivalent to:

RA (J2000): 08 02 34.07
Dec (J2000): -26 09 34.6

with an uncertainty of 1.7 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest position
can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is
described by Goad et al. (2007, A&A, 476, 1401
http://www.swift.ac.uk/xrt_positions/Goad.pdf), the current algorithm is an
extension of this method.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB080516A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7736
SUBJECT: GRB 080516, Swift-BAT refined analysis
DATE:    08/05/16 10:40:50 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

H. Krimm (GSFC/USRA), S. D. Barthelmy (GSFC), W. Baumgartner (GSFC/UMBC),
J. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC),
S. T. Holland (CRESST/USRA/GSFC), C. Markwardt (GSFC/UMD), K. McLean (GSFC/UMD),
D. Palmer (LANL), T. Sakamoto (GSFC/UMBC), G. Sato (GSFC/ISAS),
M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-240 to T+962 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 080516 (trigger #311762)
(Holland, et al., GCN Circ. 7733).  The BAT ground-calculated position is
RA, Dec = 120.661, -26.146 deg, which is 
   RA(J2000)  =  08h 02m 38.7s 
   Dec(J2000) = -26d 08' 46.9" 
with an uncertainty of 2.1 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 38%.
 
The mask-weighted light curve shows two well separated peaks.  The first peak
starts at T-0.1 sec, peaks at T+0.3 sec, and ends at T+1.0 sec.  The second
peak starts at T+3.5 sec, peaks at T+5.5 sec, and ends at T+7.5 sec.
T90 (15-350 keV) is 5.8 +- 0.3 sec (estimated error including systematics).
 
The time-averaged spectrum from T+0.1 to T+6.1 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.82 +- 0.27.  The fluence in the 15-150 keV band is 2.6 +- 0.4 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+0.05 sec in the 15-150 keV band
is 1.8 +- 0.3 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/311762/BA/


GRB_name: GRB080516A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7737
SUBJECT: GRB 080516: Swift-XRT Team refined analysis 
DATE:    08/05/16 11:08:12 GMT
FROM:    Kim Page at U.of Leicester  <kpa@star.le.ac.uk>

K.L. Page (U. Leicester) and S.T. Holland (CRESST/USRA/GSFC) report on 
behalf of the Swift-XRT team:

We have analysed the first five orbits of data obtained for GRB 080516 
(Holland et al., GCN Circ. 7733), covering 11.5 ks of Photon Counting (PC) 
mode data. The UVOT-enhanced XRT position was given by Beardmore et al. in 
GCN Circ. 7735.

The light-curve begins relatively flat, with a decay of alpha ~ 0.36 +/- 
0.17, until around 4800 seconds after the trigger, at which point the 
slope steepens to 1.04 +0.20/-0.18. 

The first five orbits of PC data can be modelled with an absorbed 
power-law, with Gamma = 2.7 +/- 0.4 and total NH = (1.3 +/- 0.3)x10^22 
cm^-2, considerably in excess of the Galactic value of 3.22x10^21 cm^-2. 
Using the relation in Grupe et al. (2007, ApJ, 133, 2216), this implies an 
estimated upper limit on the redshift of the burst of z<1.0. There is no 
evidence for spectral evolution across the temporal break. The observed 
(unabsorbed) flux over this time interval (90-2.5x10^4 s after the 
trigger) is 2.38x10^-12 (1.06x10^-11) erg cm^-2 s^-1. The counts to 
observed flux conversion is 5.8x10^-11 erg cm^-2 count^-1.

If the light-curve continues to decay at alpha ~ 1.04, the count rate at 
24 hours is predicted to be 3.7x10^-3 count s^-1, corresponding to an 
observed flux of 2.1x10^-13 erg cm^-2 s^-1.

This is an official product of the Swift-XRT team.


GRB_name: GRB080516A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7738
SUBJECT: GRB 080516, SMARTS optical/IR observations
DATE:    08/05/16 17:00:13 GMT
FROM:    Bethany Cobb at Yale U  <cobb@astro.yale.edu>

B. E. Cobb (Yale), part of the larger SMARTS consortium, reports:

Using the ANDICAM instrument on the 1.3m telescope at CTIO, we
obtained optical/IR imaging of the error region of GRB 080516
(GCN 7733, Holland et al.) with a mid-exposure time of
2008-05-16 01:27 UT (~1.2 hrs post-burst). Total summed
exposure times amounted to 36 minutes in I and 30 minutes in J.

No afterglow is detected at the enhanced Swift-XRT position
(GCN 7735, Beardmore et al.).  The 3-sigma limiting magnitudes
of our images are I>21.6 and J>19.5.  We caution, however,
that the afterglow position falls very near a I~10 mag star.
Optical photometry is calibrated against Landolt standard stars
and IR photometry is calibrated against 2MASS stars in the field.


GRB_name: GRB080430A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7739
SUBJECT: GRB080430: optical observations
DATE:    08/05/16 20:15:26 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

M. Andreev, A. Sergeev (Terskol Branch of Institute of Astronomy), Ju. 
Babina (CrAO), V. Petkov, A. Kurenya (BNO INR RAS), A. Pozanenko (IKI) on 
behalf of larger GRB follow up collaboration  report:

We observed the afterglow (Klotz et al. GCN 7646, Guidorzi et al. GCN 7647, 
Jelinek et al. GCN 7648) of GRB080430 (Guidorzi et al. GCN 7647) with 
Zeiss-600 of  Mt.Terskol observatory on May. 01.  The  afterglow is detected 
in a combined image. A photometry of the OT against USNO-B1.0 stars is 
following:

UT,              Exposure,   R_mag
(mid time)

May.01.8795 15x90s  20.9  +/-0.3

The message may be cited. 


GRB_name: GRB080516A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7740
SUBJECT: GRB 080516, GROND observations
DATE:    08/05/17 00:15:11 GMT
FROM:    Sylvio Klose at TLS Tautenburg  <klose@tls-tautenburg.de>

R. Filgas (Tautenburg), A. Kupcu-Yoldas, J. Greiner (MPE Garching),
A. Rossi, S. Klose (Tautenburg), A. Yoldas, T. Kruehler (MPE), and
G. Szokoly (Eoetvoes Univ. Budapest and MPE)
report on behalf of the GROND team:


We observed the field of GRB 080516 (Holland et al.  2008, GCN 7733)
simultaneously in g'r'i'z'JHK using the multi-channel imager GROND
(Greiner et al. 2008, PASP 120, 405) mounted at the 2.2m MPI/ESO telescope
on La Silla (Chile). Observations started at 00:25 UT, 8 min after the
burst.

At the border of the revised XRT error circle (Beardmore et al., GCN 7735)
we detect in all bands a faint source at

RA, DEC (J2000) = 08:02:33.96, -26:09:33.6  (+/- 0.5")

with r'= 23.92 +/- 0.2 at ~1 hr after the burst, calibrated against NOMAD
field stars. This source is very close to a brighter foreground point
source and close to a very bright star (Cobb et al., GCN 7738). 

Note that due to visibility constraints observations could only be
performed for two hours. Problems with the photometry did not allow us to
report these results earlier.


GRB_name: GRB080516A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7741
SUBJECT: GRB 080516, GROND 2nd epoch observations
DATE:    08/05/17 02:30:16 GMT
FROM:    Sylvio Klose at TLS Tautenburg  <klose@tls-tautenburg.de>

R. Filgas (Tautenburg), A. Kupcu-Yoldas, J. Greiner (MPE Garching),
A. Rossi, S. Klose (Tautenburg), A. Yoldas, T. Kruehler (MPE), and
G. Szokoly (Eoetvoes Univ. Budapest and MPE)
report on behalf of the GROND team:


We observed again the field of GRB 080516 (Holland et al. 2008, GCN 7733)
simultaneously in g'r'i'z'JHK using the multi-channel imager GROND. 
Observations started on May 16, 22:52 UT (22.5 hours after the burst) 
and lasted for 90 minutes.

The faint source reported in our previous circular (Filgas et al., GCN 
7740) is not detected anymore. We estimate that the source has faded by at 
least 1 magnitude. Therefore, we conclude that this was the GRB afterglow.


GRB_name: GRB080517A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7742
SUBJECT: GRB 080517: Swift detection of a burst
DATE:    08/05/17 21:51:51 GMT
FROM:    David Burrows at PSU/Swift  <dxb15@psu.edu>

A. M. Parsons (GSFC), A. P. Beardmore (U Leicester),
D. N. Burrows (PSU), J. R. Cummings (NASA/UMBC),
P. A. Evans (U Leicester), N. Gehrels (NASA/GSFC),
S. T. Holland (CRESST/USRA/GSFC), E. A. Hoversten (PSU),
C. B. Markwardt (CRESST/GSFC/UMD), F. E. Marshall (NASA/GSFC),
P. T. O'Brien (U Leicester), K. L. Page (U Leicester),
D. M. Palmer (LANL) and E. Troja (U Leicester/INAF-IASFPA) report on
behalf of the Swift Team:

At 21:22:51 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 080517 (trigger=311874).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 102.255, +50.731 which is 
   RA(J2000) = 06h 49m 01s
   Dec(J2000) = +50d 43' 51"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a single-peaked
structure with a duration of about 20 sec.  The peak count rate
was ~500 counts/sec (15-350 keV), at ~0 sec after the trigger. 

The XRT began observing the field at 21:24:57.5 UT, 125.5 seconds after
the BAT trigger. Using promptly downlinked data we find a fading,
uncatalogued X-ray source with an enhanced position: RA, Dec 102.24274,
50.73512 which is equivalent to:
   RA(J2000)  = 06h 48m 58.26s
   Dec(J2000) = +50d 44' 06.4"
with an uncertainty of 2.7 arcseconds (radius, 90% containment). This
location is 31 arcseconds from the BAT onboard position, within the BAT
error circle. We note that a known, 18th magnitude optical source lies
within our error circle; this is identified as a galaxy, EO0691-0008689,
in the APM-North survey. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density in excess of the Galactic value (8.12e+20
cm^-2, Kalberla et al. 2005), with an excess column of 2.5
(+1.70/-1.44) x 10^21 cm^-2 (90% confidence). The relation of Grupe et
al. (2007) implies that this burst has a redshift z<4.8, although high
redshift fits to the absorbed XRT spectrum are possible if paired with
an anomalously large column. A summary of the promptly downlinked data
is given at http://www.swift.ac.uk/sper/311874/. 

UVOT took a finding chart exposure of 100 seconds with the White   
(160-650 nm)  filter starting 130 seconds after the BAT trigger. A   
400 second exposure with the V filter was taken starting 236 seconds  
 after the BAT trigger.  There is no evidence for an afterglow, 
however there is a known object within the XRT error circle visible
in the UVOT images. The 2.7'x2.7' sub-image covers 100% of the XRT
error circle.  The typical  3-sigma upper limit has been about 18.5
mag in both  images. No  correction has been made for the expected
extinction  corresponding  to E(B-V) of 0.11. 

Burst Advocate for this burst is A. M. Parsons (parsons AT milkyway.gsfc.nasa.gov). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


GRB_name: GRB080517A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7743
SUBJECT: GRB080517: Liverpool Telescope Optical Observations
DATE:    08/05/17 23:09:10 GMT
FROM:    James Smith at ARI,Liverpool John Moors U  <rjs@astro.livjm.ac.uk>

R.J. Smith (Liverpool JMU), A. Gomboc (Univ. of Ljubljana, Slovenia),
A. Melandri, C. Guidorzi, M. Burgdorf, C.G. Mundell, I.A. Steele, D. 
Carter, A. Monfardini, C.J. Mottram, S. Kobayashi, D. Bersier (Liverpool 
JMU) report:

The 2-m Liverpool Telescope started observing the field of GRB 080517 
(Parsons et al. GCN 7742) at 3 min after the trigger time.

No optical transient has been located in our images to the following 
magnitude limits:

Filter      t_mid (min from GRB)    Exp (s)       Lim
------------------------------------------------------------------
R             16.08                  120          19.6
I             18.93                  120          19.2
------------------------------------------------------------------
Magnitudes were calibrated vs the USNOB1 catalogue.

In particular, comparison with Digitized Sky Survey images shows no 
obvious additional optical source in the vicinity of the known, 
moderately bright object noted to be within the XRT error circle.

Observations stopped one hour after the burst time. No further 
observations are currently planned.


GRB_name: GRB080517A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7744
SUBJECT: GRB 080517: Enhanced Swift-XRT position
DATE:    08/05/18 00:00:38 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 88 s of overlapping XRT Photon Counting mode and UVOT
data for GRB 080517, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 102.24189, +50.73496 which is equivalent
to:

RA (J2000): 06h 48m 58.05s
Dec (J2000): +50d 44' 05.8"

with an uncertainty of 1.8 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest position
can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is
described by Goad et al. (2007, A&A, 476, 1401
http://www.swift.ac.uk/xrt_positions/Goad.pdf), the current algorithm is an
extension of this method.

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB080514B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7745
SUBJECT: GRB 080514B: Further NIR observations
DATE:    08/05/18 03:40:55 GMT
FROM:    Adria C. Updike at Clemson U  <aupdike@clemson.edu>

Adria C. Updike, Ginger Bryngelson, and Dieter H. Hartmann (Clemson
University) report on behalf of the Clemson GRB Follow-Up Team:

We re-imaged the field of GRB 080514B (Hurley et al., GCN 7715) with the
KPNO 4m + NEWFIRM under good weather conditions.  We obtained 15 minutes
in the J and H bands approximately 48 hours after the trigger.  In stacked
images, we marginally detect the afterglow (Postigo et al., GCN 7719) at J
= 20.7 +/- 0.3 (calibrated to the 2MASS catalog).  We do not detect the
afterglow in the H band with a limiting magnitude of 20.2.

This message may be cited.


GRB_name: GRB080517A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7746
SUBJECT: GRB 080517: Swift-XRT refined analysis
DATE:    08/05/18 07:39:17 GMT
FROM:    Phil Evans at U of Leicester  <pae9@star.le.ac.uk>

P. A. Evans (U. Leicester) and A.M. Parsons (GSFC) report on behalf of the 
Swift-XRT team:

We have analysed the first two snapshots of Swift-XRT data obtained for 
GRB 080517 (Parsons et al, GCN Circ. 7742), comprising 3.3 ks in Photon 
Counting (PC) mode, starting 144 s after the BAT trigger. The 
UVOT-enhanced XRT position was given in Evans et al. (GCN Circ. 7744)

The light curve can be described as a broken power-law, with an initial
decay of 2.47 (+0.25/-0.23), with a break at T+~1100s to a slope of 0.57
(+0.25/-0.74).

A spectrum obtained from all of the PC data can be modelled with an
absorbed power-law, with gamma=1.91 (+0.36/-0.34) and an absorption
column of 1.41 (+0.10/1.11) e21 cm^-2, in excess of the Galactic
value of 8.12e20 cm^-2 (Kalberla et al. 2005). The observed
(unabsorbed) flux in this spectrum is 6.07 (8.12) e-12 erg cm^-2
s^-1. The counts to  observed flux conversion is 5.93e-11 erg cm^-2
count^-1.

If the light-curve continues to decay at alpha=0.57  the count rate at 
24 hours is predicted to be 1.6e-3 count s-1, corresponding to an 
observed (unabsorbed) flux of 7.10 (9.49) e-14 erg cm^-2 s^-1.

This is an official product of the Swift-XRT team.


GRB_name: GRB080516A
Detection_method: GROND
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7747
SUBJECT: GRB 080516, GROND further analysis
DATE:    08/05/18 18:03:48 GMT
FROM:    Sylvio Klose at TLS Tautenburg  <klose@tls-tautenburg.de>

R. Filgas (Tautenburg), A. Kupcu-Yoldas, J. Greiner (MPE Garching),
A. Rossi, S. Klose (Tautenburg), A. Yoldas, T. Kruehler (MPE), and
G. Szokoly (Eoetvoes Univ. Budapest and MPE)
report on behalf of the GROND team:


Our previous report (Filgas et al., GCN 7740) contains a typo in the
reported r'-band magnitude. It must be read r'=21.92 +/- 0.2 instead of 
23.92 +/- 0.2. We apologize for this mistake. 

After a re-analysis of the data, to correct for the effects of the nearby 
star, we conclude that the object is not detected in the g' band to an 
upper limit of g' > 23.0. From the SED of the afterglow, we estimate a 
photometric redshift of z = 3.2 +/- 0.3 using HyperZ (Bolzonella et al. 
2000).


GRB_name: GRB080517A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7748
SUBJECT: GRB 080517, Swift-BAT refined analysis
DATE:    08/05/18 19:34:04 GMT
FROM:    Ann M. Parsons at NASA/GSFC/Swift  <Ann.M.Parsons@nasa.gov>

C. Markwardt (GSFC/UMD), S. D. Barthelmy (GSFC), W. Baumgartner (GSFC/ 
UMBC),
J. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC), H. Krimm
(GSFC/USRA), K. McLean (GSFC/UMD), D. Palmer (LANL), A. Parsons (GSFC),
T. Sakamoto (GSFC/UMBC), G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU),
J. Tueller (GSFC), T. Ukwatta (GWU)  (i.e. the Swift-BAT team):

Using the data set from T-240 to T+962 sec from the recent telemetry  
downlink,
we report further analysis of BAT GRB 080517 (trigger #311874)  
(Parsons, et al.,
GCN Circ. 7742).

The BAT ground-calculated position is RA, Dec = 102.274, 50.741 deg  
which is
    RA(J2000)  =  06h 49m 05.8s
    Dec(J2000) = +50d 44' 28.5"
with an uncertainty of 2.4 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 50%.

The mask-weighted lightcurve shows a single, FRED-like peak rising  
quickly to
its maximum at ~T+4.4 sec with a roughly exponential decay down to  
background
at ~T+60 sec. T90 (15-350 keV) is 64.6 +- 27.2 sec (estimated error  
including
systematics).

The time-averaged spectrum from T-0.9 to T+68.3 sec is best fit by a  
simple
power-law model.  The power law index of the time-averaged spectrum is
1.54 +- 0.33.  The fluence in the 15-150 keV band is 5.6 +- 1.2 x 10^-07
erg/cm2. The 1-sec peak photon flux measured from T+3.88 sec in the
15-150 keV band is 0.6 +- 0.2 ph/cm2/sec.  All the quoted errors are  
at the
90% confidence level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/311874/BA/

This burst satisfies Sakamoto/Ukwatta Swift-BAT possible high-z criteria
(Ukwatta et al. arXiv:0802.3815).
1) PL photon index = 1.54 (PL photon index < 2)
2) 1-s peak photon flux = 0.627459 (1-s peak photon flux < 1.0 ph/cm2/s)
3) Light curve variance = 6.818773e-05 (Variance < 0.0001)
4) T90/(Peak photon flux) = 103.0 (T90/(Peak photon flux) > 100)
Based on a limited sample of bursts, these criteria yield an 85%  
chance it
has a redshift greater than 3.5. As noted in the initial Swift circular
(Parsons, et al., GCN Circ. 7742), the observed X-ray absorption implies
that the burst is most likely at z<4.8.


GRB_name: GRB080503A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7749
SUBJECT: GRB 080503: Further HST imaging
DATE:    08/05/19 03:17:20 GMT
FROM:    Daniel Perley at U.C. Berkeley  <dperley@astro.berkeley.edu>

D. A. Perley (UC Berkeley), J. S. Bloom (UCB), A. J. Levan (U. Warwick), 
W. Li (UCB), N. R. Tanvir (U. Leicester), N. R. Butler (UCB),  H-W. Chen 
(U. Chicago), R. Chornock (UCB), J. X. Prochaska (UCO/Lick), C. D. 
Bailyn (Yale), A. Bunker (U. Exeter), R. Chornock (UCB), B. Cobb (Yale), 
P. B. Hall (York U.), A. V. Filippenko (UCB), N. Gehrels (NASA/GSFC), K. 
Glazebrook (Swinburne), J. Granot (U.  Hertfordshire), K. C. Hurley 
(UCB), D. Kocevski (UCB), B. Metzger (UCB),  M. Modjaz (UCB), A. Miller 
(UCB), W. Lee (I. de Astronomia), S. Lopez (U. Chile), J. Norris 
(NASA/Ames), P. E. Nugent (LBNL), M. Pettini (U. Cambridge), D. 
Poznanski (UCB), A. L. Piro (UCB), E. Quataert (UCB), E. Ramirez-Ruiz 
(UCSC), J. Shiode (UCB), and T. Sakamoto (GSFC/UMBC) report:

Further to GCN 7703 (Bloom et al.), we obtained additional imaging using 
the Hubble Space Telescope (+WFPC2) of GRB 080503 (Mao et al., GCN 7665) 
starting at 15:05:05 on UT 2008-05-12, about 9.2 days after the trigger. 
Four exposures of 1000s each were acquired in F606W and in F814W.

The afterglow has faded significantly since the previous HST epoch, and 
is not detected in either filter, or in a combined stack of the imaging 
from both filters.  The approximate limiting magnitude is F606W(AB) > 
28.0, confirming the rapid fading observed previously.  No sign of 
host-galaxy emission is present in either filter.


GRB_name: GRB080514B
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7750
SUBJECT: GRB 080514B: second epoch Swift XRT data confirms the X-ray afterglow
DATE:    08/05/19 10:23:12 GMT
FROM:    Paolo Esposito at INAF-IASF,Milano  <paoloesp@iasf-milano.inaf.it>

P. Esposito, A. De Luca, A. Tiengo, G. Vianello (INAF-IASF MI),
K.L. Page (U. Leicester) report:

GRB 080514B was discovered by the SuperAGILE detector on May 
14th, at 09:55:56 UT (Rapisarda et al., GCN Circ. 7715) and 
possibly detected at energies E>50 MeV in AGILE GRID data 
(Giuliani et al., GCN Circ. 7716). 

The first Swift/XRT observation was performed on May 14th at 
20:12, starting about 37 ks after the GRB trigger (Page et al., 
GCN Circ. 7723). A likely afterglow candidate was found, with a 
flux decay described by a power-law (slope: 1.5+/-1.0; GCN Circ. 
7723). The spectrum was modelled with an absorbed ( 1.2x10^21 cm^-2) 
power-law, with photon index = 2.06 (GCN Circ. 7723).

Swift/XRT observed again the field of GRB 080514B on May 16th at 
20:13, about 58 hours after the trigger. 6 ks of data in Photon 
Counting mode were collected in three consecutive orbits, spanning 
5 hours.

The candidate X-ray afterglow (GCN Circ. 7723) is significantly 
detected with a 0.3-10 keV observed flux of (1.9+/-0.8)x10^-13 
erg cm^-2 s^-1 (assuming the spectrum of Circ. 7723). 

The new XRT data confirm the fading trend reported in (GCN Circ. 
7723) and better constrain the decay slope at 1.6 +0.3/-0.2. 

We thank the Swift PI, N. Gehrels, for approval of this TOO, and 
the the Swift team (in particular the duty scientists and science 
planners) for performing it.


GRB_name: GRB080514B
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7751
SUBJECT: Konus-Wind observation of GRB 080514B
DATE:    08/05/19 13:14:50 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val@mail.ioffe.ru>

S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks,
and T. Cline on behalf of the Konus-Wind team report:

The bright GRB 080514B localized by SuperAGILE/IPN (Rapisarda et al., 
GCN 7715) triggered Konus-Wind at T0=35758.672 s UT (09:55:58.672).

The burst light curve shows a multipeaked structure with a duration of
~7 s.

As observed by Konus-Wind the burst
had a fluence of 3.23(-0.26, +0.27)x10^-5 erg/cm2,
and a 16-ms peak flux measured from T0+3.328 s
of (2.07 +/- 0.43)x10^-5 erg/cm2/s
(both in the 20 keV - 5 MeV energy range).

The time-integrated spectrum of the burst
(from T0 to T0+12.032 s) is well fitted (in the 20 keV-5 MeV range)
by GRBM (Band) model for which:
the low-energy photon index is alpha = -0.599(-0.134, +0.161),
the high energy photon index beta = -2.48(-0.25, +0.18),
the peak energy Ep = 224 (-22, +23) keV (chi2 = 72.3/76 dof).

All the quoted errors are at the 90% confidence level.

The Konus-Wind light curve of this GRB is available
at http://www.ioffe.rssi.ru/LEA/GRBs/GRB080514_T35758/


GRB_name: GRB080514B
Detection_method: Suzaku WAM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7752
SUBJECT: GRB 080514B: Suzaku WAM observation of the prompt emission
DATE:    08/05/20 06:20:41 GMT
FROM:    Yoshitaka Hanabata at Hiroshima U  <hanabata@hep01.hepl.hiroshima-u.ac.jp>

Y. Hanabata, T. Uehara, Y. Fukazawa, T. Takahashi, C. Kira (Hiroshima U.), 
M. Ohno, M. Kokubun, M. Suzuki, T. Takahashi (ISAS/JAXA),
K. Yamaoka, S. Sugita (Aoyama Gakuin U.),
K. Onda, M. Tashiro, Y. Terada, Y. Urata, A. Endo, N. Kodaka,
K. Morigami, T. Sugasahara, W. Iwakiri (Saitama U.),
Y. E. Nakagawa, T. Tamagawa (RIKEN), T. Enoto, K. Nakazawa, 
K. Makishima (Univ. of Tokyo), E. Sonoda, M. Yamauchi, H. Tanaka, 
R. Hara (Univ. of Miyazaki), S. Hong (Nihon U.),
on behalf of the Suzaku WAM team, report:

The long GRB 080514B, (SuperAGILE/IPN: Rapisarda et al., GCN7715 )
triggered the Suzaku Wide-band  All-sky Monitor (WAM) 
which covers an energy range of 50 keV - 5 MeV at 09:55:57 UT (=T0). 
The observed light curve shows a multi-peaked structure 
starting at T0-1s , ending at T0+7s, with a duration (T90) of about
6.3 seconds. The fluence in 100 - 1000 keV was 1.4(+0.2,-0.1) x 10^-5
erg/cm^2. The 1-s peak flux measured from T0+2s was 11.3(+0.5,-0.1)
photons/cm^2/s in the same energy range.

A preliminary result shows that the time-averaged spectrum from 
T0-1s to T0+7s is well fitted by a GRB Band model as follows.
the low-energy photon index alpha: -1.4(+0.6,-0.5),
the upper limit of the high-energy photon index beta: -2.5
and the peak energy Epeak: 259 (+43, -104) keV (chi^2/d.o.f = 27.9/23).
----

All the quoted errors are at statistical 90% confidence level,
in which the systematic uncertainties are not included.

----
The light curves for this burst are available at:

 http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html


GRB_name: GRB080520A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  7753
SUBJECT: GRB 080520: Swift detection of a burst with optical afterglow
DATE:    08/05/20 22:49:07 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

D. Grupe (PSU), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
A. P. Beardmore (U Leicester), J. R. Cummings (NASA/UMBC),
C. Gronwall (PSU), S. T. Holland (CRESST/USRA/GSFC),
J. A. Kennea (PSU), V. Mangano (INAF-IASFPA),
K. M. McLean (GSFC/UMD), J. P. Osborne (U Leicester),
D. M. Palmer (LANL), D. Perez (U Leicester), T. Sakamoto (NASA/UMBC),
M. Stamatikos (NASA/ORAU), M. C. Stroh (PSU) and
T. N. Ukwatta (GSFC/GWU) report on behalf of the Swift Team:

At 22:20:24 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 080520 (trigger=312047).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 280.192, -55.004 which is 
   RA(J2000)  =  18h 40m 46s
   Dec(J2000) = -55d 00' 13"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows two peaks
with a duration of about 15 sec.  The peak count rate
was ~700 counts/sec (15-350 keV), at ~2 sec after the trigger. 

The XRT began observing the field at 22:22:04.3 UT, 99.5 seconds after
the BAT trigger.  Using promptly downlinked data we find a bright uncatalogued X-ray
source. The position, astrometrically enhanced by aligning promptly available
UVOT field source  positions to the USNO-B1 catalogue, is RA,Dec = 280.19337, -54.99181
(degrees) which is equivalent to:

RA  (J2000) = 18 40 46.41
DEC (J2000) = -54 59 30.5

with an uncertainty of 2.8 arcsec (radius, 90% containment). 
This position is 44.0 arcsec from the BAT position, inside the BAT
error circle. 

UVOT took a finding chart exposure of 100 seconds with the White (160-650 nm)
filter starting 106 seconds after the BAT trigger. There is a candidate
afterglow in the rapidly available 2.7'x2.7' sub-image at

RA  (J2000) =  18:40:46.41
Dec (J2000) = -54:59:31.1

with an estimated uncertainty of 0.6 arcsec (90%, radius). 
The estimated magnitude is white = 19.8 +/- 0.1 mag. No correction has been
made for Galactic extinction. 

Burst Advocate for this burst is D. Grupe (grupe AT astro.psu.edu). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)


