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GCN Circular 32139

GRB 220527A: CALET Gamma-Ray Burst Monitor detection
2022-05-28T03:10:53Z (2 years ago)
Yuta Kawakubo at Louisiana State U./CALET <>
K. Yamaoka (Nagoya U), A. Yoshida, T. Sakamoto, S. Sugita (AGU),
Y. Kawakubo (LSU), S. Nakahira (RIKEN), 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 bright long GRB 220527A (AGILE detection: Ursi et al., GCN Circ. 32129;
Fermi GBM Final Real-time Localization: Fermi GBM team, GCN Circ. 32130; 
Fermi-LAT detection: Bissaldi et al., GCN Circ. 32131) triggered the CALET
Gamma-ray Burst Monitor (CGBM) at 09:17:14.518 UTC on 27 May 2022
The burst signal was seen by all CGBM detectors.

The burst light curve shows a multi-peaked structure which starts
at T+0.5 sec, peaks at T+9.1 sec, and ends at T+21.9 sec.
The T90 and T50 durations measured by the SGM data are 10.2 +/- 1.0 sec
and 3.9 +/- 0.1 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 the Waseda University.
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