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GCN Circular 32908

GRB 221029A: CALET Gamma-Ray Burst Monitor detection
2022-11-04T04:08:43Z (2 years ago)
Yuta Kawakubo at Louisiana State U./CALET <>
S. Ricciarini (U of Florence), 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), N. Cannady (GSFC/UMBC),
M. L. Cherry (LSU), P. S. Marrocchesi (U of Siena),
and the CALET collaboration:

The long GRB 221029A (Detection by GRBAlpha: Ripa et al., GCN Circ. 32890;
Swift/BAT-GUANO detection: DeLaunay et al., GCN Circ. 32891;
Fermi GBM Final Localization: Fermi GBM team, GCN Circ. 32900;
Fermi GBM observation: Mangan et al., GCN Circ. 32903) triggered the CALET
Gamma-ray Burst Monitor (CGBM) at 01:05:26.60 UTC on 29 October 2022
The burst signal was seen by all CGBM detectors.
No real-time CGBM GCN notice was distributed about this trigger because
the real-time communication from the ISS was off (loss of signal).

The burst light curve shows a multi-peaked structure that starts
at T+0.2 sec, peaks at T+1.6 sec, and ends at T+32.4 sec.
The T90 and T50 durations measured by the SGM data are 27.6 +/- 0.8 sec
and 12.7 +/- 1.4 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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