TITLE: GCN CIRCULAR NUMBER: 27029 SUBJECT: GRB 200207A: AstroSat CZTI detection DATE: 20/02/10 10:08:46 GMT FROM: Ramkrishna Gaikwad at IUCAA/AstroSat R. Gaikwad, 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 a weak detection of long GRB 200207A, which was also detected by Fermi GBM Final Real-time Localization (GCN #27005) and Global MASTER-Net (Lipunov V. et al., GCN #27009). The source was clearly detected in the 40-200 keV energy range. The light curve showed a single peak of emission peaking at 2020-02-07 01:22:55.0 UT. The measured peak count rate associated with the burst is 146 +/- 23.0 cts/s above the background in the combined data of four quadrants, with a total of 641 +/- 14.9 cts. The local mean background count rate was 534 +/- 1.1 cts/s. Using cumulative rates, we measure a T90 of 9.2 +/- 0.04 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.