| Summary table |
|---|
| Variable |
Value |
Source |
| T0 |
23:07:02 UTC |
Swift |
| ra |
231.2040° |
Swift |
| decl |
-6.9580° |
Swift |
| pos_error |
2.23e-02° |
Swift |
| T90 |
20.4 s |
Swift |
| T90_start |
23:07:02 UTC |
Swift |
| fluence |
3.10e-06 erg/cm² |
Swift |
| T100 |
20.4 s |
|
| GBM_located |
False |
|
| mjd |
54896.963217592594 |
Swift |
| IPN table |
|---|
| GRB_name |
GRB090306B |
| ra |
231.2042° |
| decl |
-6.9500° |
| pos_error |
5.00e-02° |
| Swift table |
|---|
| GRB_name |
GRB090306B |
| t_trigger |
23:07:02 UTC |
| ra |
231.2040° |
| decl |
-6.9580° |
| pos_error |
2.23e-02° |
| T90 |
20.4 s |
| fluence |
3.10e-06 erg/cm² |
| GCN 8944 table |
|---|
| GRB_name |
GRB090306B |
| GCN_number |
8944 |
| Detection_method |
Swift-BAT Det |
| ra |
231.2040° |
| decl |
-6.9580° |
| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 8944
SUBJECT: GRB 090306B: Burst detection from Swift-BAT slew data
DATE: 09/03/07 16:50:40 GMT
FROM: Antonio Copete at Harvard U
A. Copete, J. Grindlay (Harvard)
S. Barthelmy, C. Markwardt, N. Gehrels (NASA/GSFC)
We report the detection of a bright GRB by the BAT Slew Survey (BATSS)
in the slew that started at 23:07:02 and lasted 66 sec. The ground-
calculated position is RA, Dec = 231.204, -6.958 deg, which is
RA (J2000) = 15h 24m 49s
Dec(J2000) = -06d 57' 29"
with an uncertainty of 2.87 arcmin (90% confidence, including
systematics). The detection was triggered by simultaneous independent
detections of 35.6 sigma and 20.2 sigma from imaging in the 15-50 keV
and 50-150 keV energy bands, respectively. The burst mask-tagged
lightcurve lightcurve in the 15-150 keV band shows a strong and broad
emission peak starting at T+21sec, lasting 29 sec, and peaking twice
at T+25sec and T+30sec. T90 = 20.4sec and T50 = 8.0sec.
The time-averaged spectrum over the 55 sec exposure time of the source
is best fit by a power law with an exponential cutoff, with photon
index 1.02 and high-energy cut at 133 keV. The fluence in the 15-150
keV band is 3.1 x 10^-6 erg/cm^2, and and the peak 1-sec flux is 2.5
10^-7 erg/cm^2/sec at T+30sec. A follow-up Swift ToO observation for
this burst has been scheduled.
|
| GCN 8947 table |
|---|
| GRB_name |
GRB090306B |
| GCN_number |
8947 |
| Detection_method |
Swift-XRT Other |
| ra |
231.2083° |
| decl |
-6.9682° |
| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 8947
SUBJECT: GRB 090306B: Possible XRT afterglow
DATE: 09/03/08 13:58:04 GMT
FROM: Phil Evans at U of Leicester
P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team:
Swift-XRT observed the field of the BAT Slew Survey burst GRB 090306B
(Copete et al. GCN Circ. 8944) for 5.8 ks, from T0+67 ks to T0+81 ks. The
data were entirely in PC mode.
A single, faint source is found in the BATSS error circle, with a position
RA,Dec = 231.2083, -6.9682 which is equivalent to:
RA (J2000) = 15 24 49.99
Dec (J2000) = -06 58 05.6
with an uncertainty of 4.0 arcsec (radius, 90% confidence).
We currently have only 16 counts from this source, at a count rate of 3.5
(+/- 0.9) e-3 counts s-1, and are unable to ascertain whether it is
fading.
Further observations, to verify the nature of this source, are planned.
This circular is an official product of the Swift-XRT team.
|
| GCN 8958 table |
|---|
| GRB_name |
GRB090306B |
| GCN_number |
8958 |
| Detection_method |
GROND |
| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 8958
SUBJECT: GRB 090306B: GROND Upper Limits
DATE: 09/03/09 13:29:06 GMT
FROM: Christian Clemens at MPE
A. C. Updike (Clemson University), C. Clemens, J. Greiner and P. Afonso (MPE
Garching) report on behalf of the GROND team:
We observed the field of GRB 090306B (BATSS, Copete et al., GCN #8944)
simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405)
mounted at the 2.2 m ESO/MPI telescope at La Silla Observatory (Chile).
Observations started at 04:34 UT on March 8th, about 29.5 hours after the GRB
trigger, and lasted 45 min.
We do not detect a source within the Swift-XRT error circle reported by Evans
(GCN #8947) down to (all in AB system)
g' > 23.2,
r' > 23.6,
i' > 23.3,
z' > 23.0,
J > 21.7,
H > 21.0 and
K > 20.1.
The given limits are derived based on calibrating the images against GROND
zeropoints and 2MASS field stars and are not corrected for the Galactic
foreground extinction corresponding to a reddening of E_(B-V)= 0.11 in the
direction of the burst (Schlegel et al. 1998).
|
| GCN 8968 table |
|---|
| GRB_name |
GRB090306B |
| GCN_number |
8968 |
| Detection_method |
INTEGRAL |
| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 8968
SUBJECT: GRB 090306B: INTEGRAL SPI-ACS light curve
DATE: 09/03/10 14:23:05 GMT
FROM: Volker Beckmann at ISDC
V. Beckmann, M. Beck, C. Ferrigno, N. Produit, V. Savchenko (ISDC),
J. Borkowski (CAMK/Torun), D. Gotz (CEA/Saclay), S. Mereghetti
(INAF/IASF-Milano), A. von Kienlin (MPE) report on behalf of the
INTEGRAL SPI-ACS GRB team:
GRB 090306B, detected in Swift/BAT slew data (Copete et al. GCN 8944),
has been independently detected by the SPI Anti-Coincidence
System (ACS) on-board INTEGRAL. The SPI-ACS light curve shows the peak
of the burst at 2009-03-06T23:07:21.9 with a maximum count-rate of ~390
counts/50msec. The duration of the GRB is about 14 seconds.
The SPI-ACS light curves are available (both as images and data files)
at http://isdc.unige.ch/Soft/ibas/ibas_acs_web.cgi
The light curves, binned at 50 ms, are derived from 91 independent
detectors with different lower energy thresholds (mainly between 50 keV
and 150 keV) and an upper threshold at about 100 MeV. The ACS response
varies as a function of the GRB incident angle. For these reasons we
caution that the count rates cannot be easily translated into physical
flux units.
|
| GCN 8987 table |
|---|
| GRB_name |
GRB090306B |
| GCN_number |
8987 |
| Detection_method |
Swift-XRT Other |
| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 8987
SUBJECT: GRB 090306B: Confirmation of the X-ray afterglow
DATE: 09/03/13 13:51:35 GMT
FROM: Phil Evans at U of Leicester
P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team:
Swift has performed follow-up observations of the BAT Slew Survey GRB
090306B (Copete et al, GCN Circ. 8944), gathering 4 ks of data in the
interval T0+484 ks to T0+555 ks. The X-ray source reported by Evans et
al. (GCN Circ 8947) is no longer detected, with a 3-sigma upper limit of
1.9e-3 counts/sec. We thus confirm that it was the afterglow of GRB
090306B.
This circular is an official product of the Swift-XRT team.
|