TITLE:   GCN CIRCULAR
NUMBER:  27302
SUBJECT: GRB 200228A: AstroSat CZTI detection
DATE:    20/03/03 09:45:56 GMT
FROM:    Soumya Gupta at IUCAA/ASTROSAT  <soumya@iucaa>

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 the long GRB 200228A, which was also detected by Fermi GBM Final Real-time Localization (GCN #27247), BALROG (Kunzweiler F. et al., GCN #27248) and Swift/BAT (Tohuvavohu A. et al., GRB #27259).

The source was clearly detected in the 40-200 keV energy range. The light curve showed a single peak of emission peaking at 2020-02-28 06:58:33.01 UT. The measured peak count rate associated with the burst is 537 +/- 33.1 cts/s above the background in the combined data of four quadrants, with a total of 1496 +/- 9.8 cts. The local mean background count rate was 551 +/- 1.4 cts/s. Using cumulative rates, we measure a T90 of 4.8 +/- 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.