TITLE:   GCN CIRCULAR
NUMBER:  27438
SUBJECT: GRB 200325A: AstroSat CZTI detection
DATE:    20/03/25 11:39:26 GMT
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 200325A, which was also detected by Fermi GBM (GCN #27434) and AGILE/MCAL (Ursi A. e al., GCN #27437). 

The source was clearly detected in the 40-200 keV energy range. The light curve shows a single peak of emission peaking at 2020-03-25 03:18:31 UT. The measured peak count rate associated with the burst is 185 +/- 24.5 cts/s above the background in the combined data of four quadrants, with a total of 492 +/- 21.4 cts. The local mean background count rate was 602 +/- 2.2 cts/s. Using cumulative rates, we measure a T90 of 4.9 +/- 0.12 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.