GCN Circular 42182
Subject
GRB 251006A: CALET Gamma-Ray Burst Monitor detection
Event
Date
2025-10-10T10:17:47Z (a month ago)
From
Yuta Kawakubo at Aoyama Gakuin University <kawakubo@phys.aoyama.ac.jp>
Via
Web form
T. Sakamoto, A. Yoshida, S. Sugita, Y. Kawakubo (AGU),
K. Yamaoka (Nagoya U), 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 short GRB 251006A (Fermi GBM Final Real-time Localization: Fermi GBM team, GCN Circ. 42124;
Glowbug gamma-ray detection: Cheung et al., GCN Circ. 42130;
Swift/BAT-GUANO subthreshold detection: DeLaunay et al., GCN Circ. 42144;
Fermi GBM Observation: Palafox et al., GCN Circ. 42175) triggered the CALET Gamma-ray
Burst Monitor (CGBM) at 13:27:35.21 UTC on 6 October 2025
(https://cgbm.calet.jp/cgbm_trigger/flight/1443792004/index.html).
The burst signal was seen by only the SGM detector.
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 single pulse that starts
at T-0.22 sec and ends at T+0.04 sec.
The T90 and T50 durations measured by the SGM data are 0.21 +/- 0.05 sec
and 0.11 +/- 0.05 sec (40-1000 keV), respectively.
The ground-processed light curve is available at
https://cgbm.calet.jp/cgbm_trigger/ground/1443792004/
The CALET data used in this analysis are provided by
the Waseda CALET Operation Center located at Waseda University.