[vsnet-grb-info 24772] GRB 200122A: AstroSat CZTI detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  26871
SUBJECT: GRB 200122A: AstroSat CZTI detection
DATE:    20/01/24 14:51:04 GMT
FROM:    Ramkrishna Gaikwad at IUCAA/AstroSat  <ramkrishna at iucaa.in>

R. Gaikwad, S. Gupta, V. Sharma and D. Bhattacharya (IUCAA), V. Bhalerao (IIT-B), 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 200122A, which was also detected by Swift (Sonbas E. et al., GCN #26844), Global MASTER-Net (Lipunov V. et al., GCN #26845), Swift-XRT (Osborne J. et al., GCN #26846), GOTO (Wiersema K. et al., GCN #26853), Swift/UVOT (Belles A. et al., GCN #26859), Xinglong-2.16m (Liu X. et al., GCN #26860), RATIR (Watson A. et al., GCN #26862), MITSuME Akeno ( Adachi R. et al., GCN #26864) and Konus-Wind (Frederiks D. et al., GCN #26864).

The source was clearly detected in the 40-200 keV energy range. The light curve showed multiple peak of emissions with the strongest peak at 2020-01-22 01:41:00.0 UT. The measured peak count rate associated with the burst is 74 cts/s above the background in the combined data of four quadrants, with a total of 5463 cts. The local mean background count rate was 664 cts/s. Using cumulative rates, we measure a T90 of 39.3 s.

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.