GCN Circular 27642

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 200424A, which was also detected by  INTEGRAL (Mereghetti S. et al., GCN #27634), Swift(Evans P. et al., GCN #27636) and  LCO (Strausbaugh R. et al., GCN #27637).

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 2020-04-24 12:07:18.525 UT. The measured peak count rate associated with the burst is 232 +/- 28 cts/s above the background in the combined data of four quadrants, with a total of 1849 +/- 44 cts. The local mean background count rate was 596 +/- 1 cts/s. Using cumulative rates, we measure a T90 of 43.3 +/- 0.02 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.