TITLE: GCN CIRCULAR NUMBER: 19729 SUBJECT: GRB 160720A CALET Gamma-Ray Burst Monitor detection DATE: 16/07/23 02:03:16 GMT FROM: Takanori Sakamoto at AGU S. Ozawa (Wasoeda U), A. Yoshida, T. Sakamoto, Y. Kawakubo, M. Moriyama, Y. Yamada (AGU), K. Yamaoka (Nagoya U), S. Nakahira (JAXA), I. Takahashi (IPMU), Y. Asaoka, S. Torii (Waseda U), Y. Shimizu, T. Tamura (Kanagawa U), W. Ishizaki (ICRR), M. L. Cherry (LSU), S. Ricciarini (U of Florence), P. S. Marrocchesi (U of Siena) and the CALET collaboration: The long-duration GRB 160720A (Hamburg, et al., GCN circ. 19724; Hurley, et al., GCN circ. 19726; Svinkin, et al. GCN circ. 19727; Amelushkin, et al. GCN circ. 19728) triggered the CALET Gamma-ray Burst Monitor (CGBM) at 18:25:16.38 on 20 July 2016. No real time CGBM GCN notice was distributed about this trigger because the real time communication from the ISS was off (loss of signal) between 17:57 and 18:45. The burst signal was seen by all CGBM instruments. The light curve of the SGM shows two main peaks. The emission starts at T-5 sec and ends at T+30 sec. The peak times of the main pulses are T+3 sec and T+10 sec. The 3rd weak peak is visible at T+18 sec. The T90 duration measured by the SGM data is 36.4 +- 1.7 sec (40-1000 keV). The light curve is available at http://cgbm.calet.jp/cgbm_trigger/flight/1153074224/ The CALET data used in this analysis are provided by the Waseda CALET Operation Center located at the Waseda University.