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GCN Circular 33502

GRB 230321A: CALET Gamma-Ray Burst Monitor detection
2023-03-22T04:07:36Z (6 months ago)
Yuta Kawakubo at Louisiana State U./CALET <>
N. Cannady (GSFC/UMBC), A. Yoshida, T. Sakamoto, S. Sugita (AGU),
Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN),
Y. Asaoka (ICRR), S. Torii, Y. Akaike, K. Kobayashi (Waseda U),
Y. Shimizu, T. Tamura (Kanagawa U), 
M. L. Cherry (LSU), S. Ricciarini (U of Florence),
P. S. Marrocchesi (U of Siena),
and the CALET collaboration:

The long GRB 230321A (Fermi GBM Final Real-time Localization: 
Fermi GBM team, GCN Circ. 33490; BALROG localization: Kunzweiler et al.,
GCN Circ 33491) triggered the CALET Gamma-ray Burst Monitor (CGBM)
at 04:21:42.09 UTC on 21 March 2023
The burst signal was seen by all CGBM detectors.

The burst light curve shows a multi-peaked structure that starts
at T+1.0 sec, peaks at T+31.9 sec, and ends at T+86.6 sec.
The T90 and T50 durations measured by the SGM data are 75.5 +/- 1.2 sec
and 35.4 +/- 3.1 sec (40-1000 keV), respectively.

The ground-processed light curve is available at

The CALET data used in this analysis are provided by
the Waseda CALET Operation Center located at Waseda University.
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