TITLE: GCN CIRCULAR NUMBER: 26246 SUBJECT: GRB 191027A: CALET Gamma-Ray Burst Monitor detection DATE: 19/11/14 01:02:06 GMT FROM: Valentin Pal'shin at AGU T. Tamura (Kanagawa U), A. Yoshida, T. Sakamoto, V. Pal'shin, S. Sugita (AGU), Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN), Y. Asaoka, S. Torii (Waseda U), Y. Shimizu (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: GRB 191027A (Fermi GBM Final Real-time Localization: Fermi GBM Team, GCN Circ. 26078; BALROG localization: Biltzinger et al., GCN Circ. 26079, 26096; IPN triangulation: Hurley et al., GCN Circ. 26087; Konus-Wind observation: Ridnaia et al., GCN Circ. 26100; https://gcn.gsfc.nasa.gov/other/191027A.gcn3) triggered the CALET Gamma-ray Burst Monitor (CGBM) at 15:19:06.826 UTC on 27 October 2019. The burst signal was seen by all CGBM detectors. The burst light curve shows a FRED-like pulse which starts at T+0.6 sec, peaks at T+0.9 sec and ends at T+3.0 sec. The T90 and T50 durations measured by the SGM data are 1.9 +- 0.6 sec and 0.6 +- 0.3 sec (40-1000 keV), respectively. The ground processed light curve is available at http://cgbm.calet.jp/cgbm_trigger/ground/1256224690/ The CALET data used in this analysis are provided by the Waseda CALET Operation Center located at the Waseda University.