TITLE:   GCN CIRCULAR
NUMBER:  26316
SUBJECT: GRB 191129A: AstroSat CZTI detection
DATE:    19/11/30 10:35:03 GMT
FROM:    Vidushi Sharma at IUCAA  <vidushi@iucaa.in>

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 the detection of a GRB 191129A, which was also detected by Fermi GBM Real-time Localization (GCN # 26301)and Global MASTER-Net (Lipunov V. et al., GCN # 26302).

The source was clearly detected in the 40-200 keV energy range. The light curve showed single peak of emission peaking at 2019-11-29 03:22:27.0 UT. The measured peak count rate associated with the burst is 640 cts/s above the background in the combined data of four quadrants, with a total of 8062 cts. The local mean background count rate was 412 cts/s. Using cumulative rates, we measure a T90 of 26.6 s. In preliminary analysis, we find that 538 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.