TITLE:   GCN CIRCULAR
NUMBER:  23609
SUBJECT: GRB 190103A: AstroSat CZTI detection
DATE:    19/01/05 11:44:14 GMT
FROM:    Vidushi Sharma at IUCAA  <vidushi@iucaa.in>

T. Khanam, V. Sharma and A. Vibhute (IUCAA), V. Bhalerao (IIT-B), 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 a long GRB 190103A, which was also detected by AGILE/MCAL (Ursi A. et al., GCN 23600).

The source was clearly detected in the 40-200 keV energy range. The light curve shows multiple peaks of emission with strongest peak at 16:42:16.500 UT, ~ 1 s after AGILE/MCAL trigger. The measured peak count rate is 2221 cts/s above the background in combined data of four quadrants, with a total of 10698 cts. The local mean background count rate was 486.7 cts/s. Using cumulative rates, we measure a T90 of 25.4 s. In preliminary analysis, we find that 927 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.