TITLE:   GCN CIRCULAR
NUMBER:  33361
SUBJECT: GRB 230217A: AstroSat CZTI detection
DATE:    23/02/21 08:14:53 GMT
FROM:    Gaurav Waratkar at IIT,Bombay  <gauravwaratkar@iitb.ac.in>

P K. Navaneeth (IUCAA), R. Gopalakrishnan (IUCAA), G. Waratkar (IITB), 
A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka 
University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report 
on behalf of the AstroSat CZTI collaboration:

Analysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 
2021, JApA, 42, 73) showed the detection of a short GRB230217A which was 
also detected by Fermi-GBM (Fermi GBM team, GCN Circ. 33338), Swift-BAT 
(Moss et al., GCN Circ. 33339), AGILE/MCAL (Casentini et al., GCN Circ. 
33343), Swift-XRT (Capalbi et al., GCN Circ. 33348) and Konus-Wind 
(Svinkin et al., GCN Circ. 33349).

The source was clearly detected in the 20-200 keV energy range. The 
light curve peaks at 2023-02-17 21:53:10.9 UTC. The measured peak count 
rate associated with the burst is 6691 (+436, -444) counts/s above the 
background in the combined data of all quadrants, with a total of 3487 
(+142, -172) counts. The local mean background count rate was 454 (+9, 
-10) counts/s. Using cumulative rates, we measure a T90 of 0.77 (+0.19, 
-0.07) s.

It was also 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, URSC, IUCAA, SAC, 
and PRL. The Indian Space Research Organisation funded, managed, and 
facilitated the project.