GCN Circular 27724

S. Gupta, V. Sharma and D. Bhattacharya (IUCAA), V. Bhalerao (IIT-B), A. R. Rao (IUCAA/TIFR) and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:

Analysis of AstroSat CZTI data showed the detection of a SGR 1935+2154, which was also detected by IPN (Hurley K. et al.,GCN #27714), Konus Wind (Ridnaia A. et al.,GCN #27715) and Insight-HXMT (Zhang S. et al., GCN #27718).

The source was clearly detected in the 40-200 keV energy range. The light curve showed a single peak of emission peaking at 2020-05-10 06:12:00.750 UT. The measured peak count rate associated with the burst is 3283 +/- 61 cts/s above the background in the combined data of four quadrants, with a total of 1770 +/- 3 cts. The local mean background count rate was 566 +/- 1.0 cts/s. Using cumulative rates, we measure a T90 of 0.243 +/- 0.0004 s.

It was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range.

The other burst detected by Konus Wind (UT: 21:51:17.280), wasn't detected due to Earth Occultation.

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.