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GCN Circular 35368

GRB 231215A: CALET Gamma-Ray Burst Monitor detection
2023-12-16T03:33:37Z (4 months ago)
Yuta Kawakubo at Louisiana State University <>
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N. Cannady (GSFC/UMBC), A. Yoshida, T. Sakamoto, 
S. Sugita (AGU), Y. Kawakubo (LSU), K. Yamaoka (Nagoya U),
S. Nakahira (JAXA), Y. Asaoka (ICRR), S. Torii, Y. Akaike, 
K. Kobayashi (Waseda U), T. Tamura, Y. Shimizu (Kanagawa U),
M. L. Cherry (LSU), S. Ricciarini (U of Florence),
P. S. Marrocchesi (U of Siena),
and the CALET collaboration:

The long GRB 231215A (Swift detection of a burst: D'Avanzo et al., 
GCN Circ. 35343; AstroSat CZTI detection: Navaneeth et al., 
GCN Circ. 35352; AGILE detection: Verrecchia et al., GCN Circ. 
35361) triggered the CALET Gamma-ray Burst Monitor 
(CGBM) at 09:47:15.26 UTC on 15 December 2023
The burst signal was seen by all CGBM detectors.

The burst light curve shows a multi-peaked structure that starts
at T+1.5 sec, peaks at T+10.4 sec, and ends at T+20.4 sec.
The T90 and T50 durations measured by the SGM data are 
15.2 +/- 1.3 sec and 5.6 +/- 0.2 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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