TITLE: GCN CIRCULAR NUMBER: 23875 SUBJECT: GRB 190202A: AstroSat CZTI detection DATE: 19/02/05 06:45:51 GMT FROM: Vidushi Sharma at IUCAA V. Sharma, T. Khanam 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 190202A, which was also detected by Swift (Lien A. Y. et al., GCN Circ 23830), AGILE ratemeters (Verrecchia F. et al., GCN Circ 23835) and Fermi GBM (Veres P. et al., GCN Circ 23838). The source was clearly detected in the 20-200 keV energy range. The light curve shows multiple peaks of emission with the strongest peak at 01:39:31.5 UT. The measured peak count rate is 453 cts/s above the background in the combined data of four quadrants, with a total of 3173 cts. The local mean background count rate was 471 cts/s. Using cumulative rates, we measure a T90 of 14.8 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.