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GCN Circular 34189

GRB 230707B: CALET Gamma-Ray Burst Monitor detection
2023-07-10T07:10:03Z (10 months ago)
Yuta Kawakubo at Louisiana State University <>
S. Torii (Waseda U), A. Yoshida, T. Sakamoto, S. Sugita (AGU),
Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (JAXA),
Y. Asaoka (ICRR), 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 230707B (Fermi GBM Final Real-time Localization: 
Fermi GBM team, GCN Circ. 34165; Swift/BAT-GUANO detection: 
DeLaunay et al., GCN Circ. 34169) triggered the CALET Gamma-ray
Burst Monitor (CGBM) at 18:46:18.95 UTC on 7 July 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+82.1 sec, and ends at T+108.1 sec.
The T90 and T50 durations measured by the SGM data are 94.6 +/- 1.6 sec
and 52.1 +/- 1.2 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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