GCN Circular 24536

Y. Sharma and V. Bhalerao (IIT-B), T. Khanam, V. Sharma and A. Vibhute (IUCAA), D. Bhattacharya (IUCAA), 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 long duration GRB 180416D in the 40-200 keV energy range. The light curve shows weak multiple peak emission starting at 04:25:07 (UT). The measured peak count rate is 130 cts/s above the background in combined data of four quadrants, with a total of 6014 cts. The local mean background count rate was 525 cts/s. Using cumulative rates, we measure a T90 of 96.6 s.

The GRB was clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range with 165 cts/s peak count rate above background in combined data of four quadrants.

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.