TITLE: GCN CIRCULAR NUMBER: 27462 SUBJECT: GRB 200326B: AstroSat CZTI detection DATE: 20/03/28 12:29:36 GMT FROM: Soumya Gupta at IUCAA/ASTROSAT 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.