TITLE: GCN CIRCULAR NUMBER: 42182 SUBJECT: GRB 251006A: CALET Gamma-Ray Burst Monitor detection DATE: 25/10/10 10:17:47 GMT FROM: Yuta Kawakubo at Aoyama Gakuin University <kawakubo@phys.aoyama.ac.jp> 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. View this GCN Circular online at https://gcn.nasa.gov/circulars/42182. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...