GCN Circular 21855

S. Ricciarini (U of Florence), A. Yoshida, T. Sakamoto, Y. Kawakubo,
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), A. V. Penacchioni, P. S. Marrocchesi (U of Siena)
and the CALET collaboration:

The long-duration GRB 170830B (Fermi-GBM trigger #525772316;
Konus-Wind trigger time on 07:51:50.164 UT; INTEGRAL-SPI/ACS trigger
#7903,0) triggered the CALET Gamma-ray Burst Monitor (CGBM) at 07:51:52.372
on 30 August 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 single peak.  The emission starts at
T0 sec, peaks at T+2 sec and ends at T+3.5 sec.  The T90 duration measured
by the SGM data is 3.3 +- 0.5 sec (40-1000 keV).

The light curve is available at

http://cgbm.calet.jp/cgbm_trigger/flight/1188114098/

The CALET data used in this analysis are provided by the Waseda
CALET Operation Center located at the Waseda University.