TITLE:   GCN CIRCULAR
NUMBER:  22268
SUBJECT: GRB 171216B CALET Gamma-Ray Burst Monitor detection
DATE:    17/12/23 00:36:54 GMT
FROM:    Takanori Sakamoto at AGU  <tsakamoto@phys.aoyama.ac.jp>

V. Pal'shin, 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),
S. Ricciarini (U of Florence), A. V. Penacchioni, P. S. Marrocchesi (U of Siena)
and the CALET collaboration:

The bright GRB 171216B (INTEGRAL SPI-ACS trigger #7972; Hurley et al.
GCN circ. 22263) triggered the CALET Gamma-ray Burst Monitor (CGBM) at
14:25:47.14 on 16 December 2017.  The burst signal was seen by the all instruments.

The light curve of the SGM shows several short peaks. The emission starts
at T0, peaks at T+3 sec and ends at T+5 sec.  The T90 duration measured
by the SGM data is 3.5 +- 0.4 sec (40-1000 keV).

The ground processed light curve is available at

http://cgbm.calet.jp/cgbm_trigger/ground/1197469387/

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