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GCN Circular 35842

GRB 240229A: CALET Gamma-Ray Burst Monitor detection
2024-03-01T04:42:26Z (4 months ago)
Yuta Kawakubo at Louisiana State University <>
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K. Yamaoka (Nagoya U), A. Yoshida, T. Sakamoto, S. Sugita (AGU),
Y. Kawakubo (LSU), S. Nakahira (JAXA), Y. Asaoka (ICRR), S. Torii,
Y. Akaike, K. Kobayashi (Waseda U), Y. Shimizu, T. Tamura (Kanagawa U),
N. Cannady (GSFC/UMBC), M. L. Cherry (LSU), S. Ricciarini (U of Florence),
P. S. Marrocchesi (U of Siena),
and the CALET collaboration:

The long GRB 240229 (Fermi GBM Final Real-time Localization: 
Fermi GBM team, GCN Circ. 35833; BALROG localization: Biltzinger et al.,
GCN Circ 35834; INTEGRAL SPI ACS: Trigger Num. 10602)
triggered the CALET Gamma-ray Burst Monitor (CGBM) at 
14:07:07.40 UTC on 29 February 2024
The burst signal was seen by all CGBM detectors.

The burst light curve shows a double-peaked structure that starts
at T+2.9 sec, peaks at T+26.5 sec, and ends at T+36.8 sec.
The T90 and T50 durations measured by the SGM data are 27.6 +/- 2.5 sec
and 19.2 +/- 0.4 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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