TITLE: GCN CIRCULAR NUMBER: 19519 SUBJECT: GRB 160508A: Astrosat CZTI detection DATE: 16/06/10 11:22:12 GMT FROM: Varun Bhalerao at IUCAA 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 detection of GRB 160508A (Marrocchesi et al., GCN 19422; INTEGRAL-ACS trigger #7459; Konus-Wind trigger time on 14:32:38.795 UT) in CZTI data. The source was clearly detected in the 40-240 keV energy range. The light curve shows a single peak at UT 14:32:37.7 and a peak count rate of 416.6 counts/sec above the background (four quadrants summed together), with a total of 3373 counts. The local mean background count rate was 84.0 counts/sec. Using cumulative rates, we measure a T90 of 25.0 secs. CZTI GRB detections are reported regularly on the payload site at http://astrosat.iucaa.in/czti/?q=node/9. 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.