[vsnet-grb-info 19759] GRB 170830A: Astrosat CZTI detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  21773
SUBJECT: GRB 170830A: Astrosat CZTI detection
DATE:    17/08/31 13:22:08 GMT
FROM:    Vidushi Sharma at IUCAA  <vidushi at iucaa.in>

V. Bhalerao (IITB), V. Sharma and 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 clear detection of GRB 170830A (MAXI/GSC detection: Yoneyama T. et al., GCN Circ. 21761) in the 40-200 keV energy range. The light curve shows multiple peaks of emission with the strongest peak at 03:14:00 UT, ~89 s before the MAXI/GSC trigger. The measured peak count rate is 66.3 counts/sec above the background in combined data of four quadrants, with a total of 91.4 counts. The local mean background count rate was 395.1 counts/sec. Using cumulative rates, we measure a T90 of 57.6 secs.

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.