TITLE:   GCN CIRCULAR
NUMBER:  27680
SUBJECT: AstroSat CZTI detection : GRB200503A
DATE:    20/05/03 13:05:09 GMT
FROM:    Soumya Gupta at IUCAA/ASTROSAT  <soumya@iucaa>

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 a long GRB 200503A.
The source was clearly detected in the 40-200 keV energy range. The light curve shows multiple peaks of emission with the strongest peak at 2020-05-03 05:02:01.500 UT. The measured peak count rate associated with the burst is 2021 +/- 50.3 cts/s above the background in the combined data of four quadrants, with a total of 28736 +/- 52.5 cts. The local mean background count rate was 601 +/- 1.0 cts/s. Using cumulative rates, we measure a T90 of 38.6 +/- 0.01 s. In preliminary analysis, we find that 2294 Compton events are associated with this event.
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.