| Summary table |
|---|
| Variable |
Value |
Source |
| T0 |
0:19:40 UTC |
GCN_circulars,Swift Det |
| ra |
101.1050° |
Swift |
| decl |
-62.0058° |
Swift |
| pos_error |
4.66e-04° |
Swift |
| GBM_located |
False |
|
| mjd |
58914.013657407406 |
GCN_circulars,Swift Det |
| IPN table |
|---|
| GRB_name |
GRB200306A |
| ra |
101.1042° |
| decl |
-62.0000° |
| pos_error |
5.00e-02° |
| Swift table |
|---|
| GRB_name |
GRB200306A |
| t_trigger |
0:19:40 UTC |
| ra |
101.1050° |
| decl |
-62.0058° |
| pos_error |
4.66e-04° |
| GCN 27320 table |
|---|
| GRB_name |
GRB200306A |
| GCN_number |
27320 |
| Detection_method |
Swift Det |
| t_trigger |
0:19:40 UTC |
| ra |
101.1050° |
| decl |
-62.0058° |
| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 27320
SUBJECT: GRB 200306A: Swift detection of a burst
DATE: 20/03/06 00:38:35 GMT
FROM: David Palmer at LANL
K. K. Simpson (PSU), D. M. Palmer (LANL) and B. Sbarufatti (PSU)
report on behalf of the Neil Gehrels Swift Observatory Team:
At 00:19:40 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 200306A (trigger= 959917). Swift slewed immediately to the burst.
Due to communications outages, no BAT data is immediately available at this
time, but the complete data set will be available after upcoming downlinks
to the ground.
Using promptly downlinked data we find a bright, uncatalogued X-ray
source with an enhanced position: RA, Dec 101.1050, -62.0058 which is
equivalent to:
RA(J2000) = 06h 44m 25.20s
Dec(J2000) = -62d 00' 20.9"
with an uncertainty of 3.6 arcseconds (radius, 90% containment). This
position may be improved as more data are received; the latest position
is available at https://www.swift.ac.uk/sper.
A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of 8.67
x 10^20 cm^-2 (Willingale et al. 2013).
The initial flux in the 2.5 s image was 3.02e-09 erg cm^-2 s^-1 (0.2-10
keV).
UVOT took a finding chart exposure of nominal 150.000 seconds with the
White filter starting 85s seconds after the BAT trigger. Automatic
processing failed because of connectivity issues on the ground.
Further analysis will be available once the full dataset gets on the
ground.
Burst Advocate for this burst is K. K. Simpson (kira.simpson1984 AT gmail.com).
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/)
|
| GCN 27321 table |
|---|
| GRB_name |
GRB200306A |
| GCN_number |
27321 |
| Detection_method |
Swift Other |
| ra |
101.1055° |
| decl |
-62.0049° |
| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 27321
SUBJECT: GRB 200306A: Potential LCO Optical Afterglow Detection
DATE: 20/03/06 06:15:31 GMT
FROM: Robert Strausbaugh at U. of the Virgin Islands
R. Strausbaugh (U. of the Virgin Islands), A. Cucchiara (U. of the Virgin Islands/College of Marin) report on behalf of a larger collaboration:
We observed Swift GRB 200306A (Simpson et al., GCN 27320) with the LCO 1-m Sinistro instrument at the Cerro Tololo Interamerican Observatory, Chile site, on March 6, from 1:06 to 1:46 UT (corresponding to 0.78 to 1.45 hours from the GRB trigger time) with the Bessel I and R filters.
We performed a series of 5x240s exposures in I and R. We detect a faint source in stacked R band images within the XRT error region that is not present in USNO or 2MASS catalogs. We do not detect a source in stacked I band images. Using the USNO-B.1 catalog as reference, we obtain the following magnitude detection in R at RA,DEC=101.1054814,-62.0049360 and the following 3-sigma upper limit in I:
R = 21.75
I > 21.52
R.S. is funded by NSF AST grant #1831682
|
| GCN 27331 table |
|---|
| GRB_name |
GRB200306A |
| GCN_number |
27331 |
| Detection_method |
Swift-XRT Other |
| ra |
101.1023° |
| decl |
-62.0065° |
| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 27331
SUBJECT: GRB 200306A: Swift-XRT refined Analysis
DATE: 20/03/07 00:38:06 GMT
FROM: Phil Evans at U of Leicester
J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), E. Ambrosi
(INAF-IASFPA) , M. Capalbi (INAF-IASFPA), M. Perri (ASDC), B.
Sbarufatti (PSU), D.N. Burrows (PSU), J. D. Gropp (PSU), A.P. Beardmore
(U. Leicester) and K.K. Simpson report on behalf of the Swift-XRT team:
We have analysed 2.1 ks of XRT data for GRB 200306A (Simpson et al. GCN
Circ. 27320), from 66 s to 6.2 ks after the BAT trigger. The data
comprise 186 s in Windowed Timing (WT) mode (the first 9 s were taken
while Swift was slewing) with the remainder in Photon Counting (PC)
mode. Using 2051 s of PC mode data and 6 UVOT images, we find an
enhanced XRT position (using the XRT-UVOT alignment and matching UVOT
field sources to the USNO-B1 catalogue): RA, Dec = 101.10233, -62.00654
which is equivalent to:
RA (J2000): 06h 44m 24.56s
Dec(J2000): -62d 00' 23.5"
with an uncertainty of 1.5 arcsec (radius, 90% confidence).
The light curve can be modelled with a power-law decay with a decay
index of alpha=4.05 (+/-0.21).
A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.93 (+/-0.14). The
best-fitting absorption column is 5.2 (+/-0.5) x 10^21 cm^-2, in
excess of the Galactic value of 8.6 x 10^20 cm^-2 (Willingale et al.
2013). The PC mode spectrum has a photon index of 1.89 (+0.19, -0.18)
and a best-fitting absorption column of 4.3 (+1.1, -0.9) x 10^21 cm^-2.
The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum is 4.2 x 10^-11 (6.3 x 10^-11) erg cm^-2
count^-1.
A summary of the PC-mode spectrum is thus:
Total column: 4.3 (+1.1, -0.9) x 10^21 cm^-2
Galactic foreground: 8.6 x 10^20 cm^-2
Excess significance: 6.0 sigma
Photon index: 1.89 (+0.19, -0.18)
If the light curve continues to decay with a power-law decay index of
4.05, the count rate at T+24 hours will be 3.6 x 10^-11 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.5 x
10^-21 (2.3 x 10^-21) erg cm^-2 s^-1.
The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00959917.
This circular is an official product of the Swift-XRT team.
|
| GCN 27340 table |
|---|
| GRB_name |
GRB200306A |
| GCN_number |
27340 |
| Detection_method |
AstroSat CZTI |
| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 27340
SUBJECT: GRB 200306A: AstroSat CZTI detection
DATE: 20/03/07 16:08:56 GMT
FROM: Soumya Gupta at IUCAA/ASTROSAT
S. Gupta, V. Sharma, A. Vibhute and D. Bhattacharya (IUCAA), V. Bhalerao (IIT-B), A. R. Rao (TIFR) and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:
Analysis of AstroSat CZTI data showed the detection of the long GRB 200306A, which was also detected by Global MASTER-Net (Lipunov V. et al., GCN #27319), Swift (Simpson K. et al., GCN #27320) and Potential LCO (Strausbaugh R. et al., GCN #27321).
The source was clearly detected in the 40-200 keV energy range. The light curve showed multiple peaks of emission with the strongest peak at 2020-03-06 00:19:55.46 UT. The measured peak count rate associated with the burst is 323 +/- 20.4 cts/s above the background in the combined data of four quadrants, with a total of 5603 +/- 41.2 cts. The local mean background count rate was 525 +/- 0.9 cts/s. Using cumulative rates, we measure a T90 of 33.7 +/- 0.07 s.
CZTI GRB detections are reported regularly on the payload site at http://astrosat.iucaa.in/czti/?q=grb.
CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC and PRL. The Indian Space Research Organisation funded, managed and facilitated the project.
|
| GCN 27343 table |
|---|
| GRB_name |
GRB200306A |
| GCN_number |
27343 |
| Detection_method |
Swift-BAT Det |
| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 27343
SUBJECT: GRB 200306A: RATIR Optical Observations
DATE: 20/03/07 21:07:13 GMT
FROM: Alan M Watson at UNAM
Alan M. Watson (UNAM), Nat Butler (ASU), Alexander Kutyrev (GSFC),
William H. Lee (UNAM), Michael G. Richer (UNAM), Ori Fox (STScI), J.
Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (UVI),
Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz
(UCSC), Jesús González (UNAM), Carlos Román-Zúñiga (UNAM), Harvey
Moseley (GSFC), John Capone (UMD), V. Zach Golkhou (U. Wash.), and Vicki
Toy (UMD) report:
We observed the field of GRB 200306A (Gropp et al., GCN Circ. 27326)
with the Reionization and Transients Infrared Camera (RATIR;
www.ratir.org) on the 1.5m Harold Johnson Telescope at the Observatorio
Astronómico Nacional on Sierra San Pedro Mártir from 2020/03 7.27 to
2020/03 7.54 UTC (7.61 to 14.01 hours after the BAT trigger), obtaining
a total of 4.31 hours exposure in the r and i bands.
For a source within the Swift-XRT error circle, in comparison with the
SDSS DR9 catalog, we obtain the following 3-sigma upper limits :
r > 23.34
i > 23.71
These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB.
We thank the staff of the Observatorio Astronómico Nacional in San Pedro
Mártir.
|
| GCN 27346 table |
|---|
| GRB_name |
GRB200306A |
| GCN_number |
27346 |
| Detection_method |
Swift-BAT Det |
| ra |
101.1140° |
| decl |
-62.0100° |
| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 27346
SUBJECT: GRB 200306A: Swift-BAT refined analysis
DATE: 20/03/07 23:12:45 GMT
FROM: Amy Lien at GSFC
T. Sakamoto (AGU), S. D. Barthelmy (GSFC),
J. R. Cummings (CPI), H. A. Krimm (NSF),
S. Laha (GSFC/UMBC), A. Y. Lien (GSFC/UMBC),
C. B. Markwardt (GSFC), D. M. Palmer (LANL),
K. K. Simpson (PSU), M. Stamatikos (OSU),
T. N. Ukwatta (LANL) (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 200306A (trigger #959917)
(Simpson et al., GCN Circ. 27320). The BAT ground-calculated position is
RA, Dec = 101.114, -62.010 deg which is
RA(J2000) = 06h 44m 27.3s
Dec(J2000) = -62d 00' 34.4"
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 75%.
The mask-weighted light curve shows a few overlapping pulses
that starts at ~T-4 s and ends at ~T+50 s. The main peak
occurs at ~T+20 s. T90 (15-350 keV) is 32.87 +- 1.13 sec
(estimated error including systematics).
The time-averaged spectrum from T-3.67 to T+49.95 sec is best fit by a
power law
with an exponential cutoff. This fit gives a photon index 1.06 +- 0.15,
and Epeak of 81.6 +- 6.9 keV (chi squared 32.91 for 56 d.o.f.). For this
model the total fluence in the 15-150 keV band is 1.0 +- 0.02 x 10^-5
erg/cm2
and the 1-sec peak flux measured from T+20.11 sec in the 15-150 keV band is
7.0 +- 0.3 ph/cm2/sec. A fit to a simple power law gives a photon index
of 1.70 +- 0.03 (chi squared 98.65 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/959917/BA/
|
| GCN 27351 table |
|---|
| GRB_name |
GRB200306A |
| GCN_number |
27351 |
| Detection_method |
Swift-UVOT Other |
| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 27351
SUBJECT: GRB 200306A: Swift/UVOT Upper Limits
DATE: 20/03/08 22:55:27 GMT
FROM: Sam LaPorte at PSU
GRB 200306A: Swift/UVOT Upper Limits
J. D. Gropp (PSU) and K. K. Simpson (PSU)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 200306A
85 s after the BAT trigger (Simpson et al., GCN Circ. 27320).
No optical afterglow consistent with the optical position
(Strausbaugh et al., GCN Circ. 27321)
is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and subsequent exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
white_FC 85 235 147 >21.0
white 85 6191 459 >20.7
v 5049 11928 1011 >20.1
b 4434 16845 1278 >20.5
u 297 5864 351 >20.1
w1 5459 5659 197 >19.7
m2 5254 5454 197 >19.1
w2 4844 11087 1082 >20.3
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.10 in the direction of the burst
(Schlegel et al. 1998).
|