[vsnet-grb-info 18293] GRB160720A: Astrosat CZTI detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  19741
SUBJECT: GRB160720A: Astrosat CZTI detection
DATE:    16/07/29 04:25:22 GMT
FROM:    Varun Bhalerao at IUCAA  <varunb at 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 GRB 160720A (Fermi-GBM detection: Hamburg and Burns, GCN Circ. 19724).

The source was clearly detected in the 40-200 keV energy range. The light curve shows a complex structure, with the strongest peak at 18:25:25 UT, 88 seconds after Fermi Trigger at 18:23:57.00 UT and a peak count rate of 318.0 counts/sec above the background (four quadrants summed together), with a total of 1813.0 counts. The local mean background count rate was 283.0 counts/sec. Using cumulative rates, we measure a T90 of 21.0 secs.

The center of the IPN Triangulation region (Hurley et al., GCN Circ.  19726) is at an angle of 143 degrees from the CZTI pointing direction.

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.