GRB 211227A: CALET Gamma-Ray Burst Monitor detection
Abstract
The long GRB 211227A (Swift detection and refined analysis: Beardmore et al., GCN Circ. 31316, Lien et al., GCN Circ. 31326; MAXI/GSC detection: Tominaga et al., GCN Circ. 31319; https://gcn.gsfc.nasa.gov/other/211227A.gcn3) triggered the CALET Gamma-ray Burst Monitor (CGBM) at 23:32:07.476 UTC on 27 December 2021. The burst signal was seen by all CGBM detectors. Because of a problem in one of the ground alert processing script, the GCN notice was not distributed automatically for this event. The burst light curve shows a multi-peaked structure which starts at T-0.6 sec and ends at T+77.2 sec. The T90 and T50 durations measured by the SGM data are 64.5 +- 10.3 sec and 22.0 +- 2.0 sec (40-1000 keV), respectively. The ground processed light curve is available at http://cgbm.calet.jp/cgbm_trigger/ground/1324683113/ The CALET data used in this analysis are provided by the Waseda CALET Operation Center located at the Waseda University.
- Publication:
-
GRB Coordinates Network
- Pub Date:
- December 2021
- Bibcode:
- 2021GCN.31333....1C