TITLE:   GCN CIRCULAR
NUMBER:  23856
SUBJECT: GRB 190204A: AstroSat CZTI detection
DATE:    19/02/04 11:43:22 GMT
FROM:    Vidushi Sharma at IUCAA  <vidushi@iucaa.in>

T. Khanam, V. Sharma, D. Bhattacharya and  A. Vibhute (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 190204A, which was also detected by Swift (Lien A. Y. et al., GCN Circ 23852) and MAXI/GSC (Oeda T. et al., GCN Circ 23854).

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 05:46:06.5 UT. The measured peak count rate is 1455 cts/s above the background in the combined data of four quadrants, with a total of 5579 cts. The local mean background count rate was 569 cts/s. Using cumulative rates, we measure a T90 of 11.9 s. In preliminary analysis, we find that 578 Compton events are associated with this event.

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.