TITLE:   GCN CIRCULAR
NUMBER:  19739
SUBJECT: GRB160703A: Astrosat CZTI detection
DATE:    16/07/29 04:23:54 GMT
FROM:    Varun Bhalerao at IUCAA  <varunb@iucaa.in>

V. Bhalerao (IUCAA), V. Kumar (IUCAA), D. Bhattacharya (IUCAA), A. R. Rao (TIFR), S. Vadawale (PRL) report on behalf of the Astrosat CZTI collaboration:

Analysis of Astrosat data showed the CZTI detection of a long duration GRB 160703A (Swift/BAT observation:Cenko et al., GCN 19645, Swift/BAT triggered at 12:10:05 UT).

The GRB occured at an angle of 134 degrees away from the CZTI pointing direction. The source was clearly detected in the 40-200 keV energy range.  The light curve shows a complex structure, with a peak at UT 12:10:27.000. The peak count rate was 360.40 counts/sec above the background (four quadrants summed together), with a total of 5022.0 counts. The local mean background count rate was 352.0 counts/sec. Using cumulative rates, we measure a T90 of 45.0 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.