[vsnet-grb-info 21412] GRB 180112B: AstroSat CZTI detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  23511
SUBJECT: GRB 180112B: AstroSat CZTI detection
DATE:    18/12/05 05:52:28 GMT
FROM:    Varun Bhalerao at Indian Inst of Tech  <varunb at iitb.ac.in>

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 180112B in the 40-200 keV energy range. The light curve shows weak multiple peak emission starting at 20:12:26 (UT). The measured peak count rate is 283 cts/s above the background in combined data of four quadrants, with a total of 823 cts. The local mean background count rate was 441.4 cts/s. Using cumulative rates, we measure a T90 of 8.48 s.

The GRB was clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range with 324.17 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.