GRB 200326B
GCN Circular 27454
Subject
GRB 200326B: AstroSat LAXPC detection
Date
2020-03-27T12:41:54Z (5 years ago)
From
Tilak Katoch at TIFR <tilak@tifr.res.in>
H. M. Antia, Tilak Katoch, Parag Shah and Dhiraj Dedhia
TIFR, Mumbai, India.
Analysis of AstroSat LAXPC data showed the detection of a long
GRB 200326B. The light curve showed a double peak profile
triggered at T0 = 21h 13m 52s UT on 26 Mar 2020, with T90=10 sec
for the first peak followed by a second smaller peak of similar
duration about 10 s later. The measured peak count rate above the
background associated with the burst is 158 +/- 24 cts/s in
LAXPC10 and 171 +/- 20 cts/s in LAXPC20 at T0+3 sec. The total
counts in the first peak are 542 +/- 71 cts in LAXPC10 and
773 +/- 54 in LAXPC20.
Both LAXPC instruments (LAXPC10 and LAXPC20) have registered this
burst profile in the light curve. For LAXPC20 the nominal energy
range is 3-100 keV, but due to lower gain in LAXPC10 the energy
range is about 30-400 keV.
The background subtracted light curve with 1 sec time-bin is
available at the web-site:
https://www.tifr.res.in/~astrosat_laxpc/grb200326blc.jpg
LAXPC was built by TIFR in collaboration with the Indian Space
Research Organisation. The Indian Space Research Organisation
funded, managed and facilitated the project.
GCN Circular 27462
Subject
GRB 200326B: AstroSat CZTI detection
Date
2020-03-28T12:29:36Z (5 years ago)
From
Soumya Gupta at IUCAA/ASTROSAT <soumya@iucaa>
S. Gupta, V. Sharma 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 a long GRB 200326B, which was also detected by AstroSat LAXPC (Antia H. et al., GCN #27454).
The source was clearly detected in the 40-200 keV energy range. The light curve shows a single peak of emission peaking at 2020-03-26 21:13:52 UT. The measured peak count rate associated with the burst is 146 +/- 23.5 cts/s above the background in the combined data of four quadrants, with a total of 354 +/- 10.6 cts. The local mean background count rate was 546 +/- 1.3 cts/s. Using cumulative rates, we measure a T90 of 8.1 +/- 0.6 s.
It was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range.
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.