TITLE: GCN CIRCULAR NUMBER: 28255 SUBJECT: GRB 200815A: CALET Gamma-Ray Burst Monitor detection of a short burst DATE: 20/08/17 12:01:19 GMT FROM: Valentin Pal'shin at AGU K. Kobayashi (Waseda U), A. Yoshida, T. Sakamoto, V. Pal'shin, S. Sugita (AGU), Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN), Y. Asaoka (ICRR), S. Torii, Y. Akaike (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: At 21:02:43.555 UTC on 15 August 2020, the CALET Gamma-ray Burst Monitor (CGBM) triggered on short GRB 200815A. The burst signal was seen mainly by the SGM detector. Because of a problem in one of the ground alert processing script, the GCN notice was not distributed automatically for this event. This short GRB is also clearly seen by the publicly available INTEGRAL SPI-ACS light curve. The burst light curve shows a short pulse which starts at T-0.056 sec, peaks at T-0.040 sec and ends at T+0.064 sec. The T90 and T50 durations measured by the SGM data are 0.104 +- 0.025 sec and 0.056 +- 0.008 sec (40-1000 keV), respectively. The ground processed light curve is available at http://cgbm.calet.jp/cgbm_trigger/ground/1281560544/ The CALET data used in this analysis are provided by the Waseda CALET Operation Center located at the Waseda University.