TITLE: GCN CIRCULAR NUMBER: 22111 SUBJECT: GRB 171102A CALET Gamma-Ray Burst Monitor detection DATE: 17/11/09 00:46:12 GMT FROM: Takanori Sakamoto at AGU Y. Kawakubo, A. Yoshida, T. Sakamoto, M. Moriyama, Y. Yamada, A. Tezuka, S. Matsukawa (AGU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN), I. Takahashi (IPMU), Y. Asaoka, S. Ozawa, S. Torii (Waseda U), Y. Shimizu, T. Tamura (Kanagawa U), W. Ishizaki (ICRR), M. L. Cherry (LSU), S. Ricciarini (U of Florence), A. V. Penacchioni, P. S. Marrocchesi (U of Siena) and the CALET collaboration: The long-duration GRB 171102A (Yassine et al., GCN circ. 21615; Stanbro et al., GCN circ. 22083; Kozlova et al., GCN circ. 22091; Tsvetkova et al., GCN circ. 22094; INTEGRAL SPI-ACS trigger #7955) triggered the CALET Gamma-ray Burst Monitor (CGBM) at 02:33:36.14 on 2 November 2017. The burst signal was seen by the all CGBM instruments. Because of a problem in one of the ground alert processing script, the GCN notice was not distributed automatically for this event. The light curve of the SGM shows a complex structure with a precursor around T0. The precursor emission starts at T-2 sec and ends at T+2 sec. The main burst episode starts at T+30 sec, peaks at T+48 sec and ends at T+60 sec. The T90 duration measured by the SGM data is 21.9 +- 0.3 sec (40-1000 keV). The light curve is available at http://cgbm.calet.jp/cgbm_trigger/flight/1193625133/ The CALET data used in this analysis are provided by the Waseda CALET Operation Center located at the Waseda University.