TITLE:   GCN CIRCULAR
NUMBER:  22307
SUBJECT: GRB 171230A CALET Gamma-Ray Burst Monitor detection
DATE:    18/01/08 05:53:18 GMT
FROM:    Takanori Sakamoto at AGU  <tsakamoto@phys.aoyama.ac.jp>

I. Takahashi (IPMU), A. Yoshida, T. Sakamoto, V. Pal'shin, Y. Kawakubo,
M. Moriyama, Y. Yamada, A. Tezuka, S. Matsukawa (AGU), K. Yamaoka (Nagoya U),
S. Nakahira (RIKEN), 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 171230A (Fermi-GBM trigger #536288993;
Konus-Wind trigger time on 01:09:48.119) triggered the CALET
Gamma-ray Burst Monitor (CGBM) at 01:09:46.31 on 30 December 2017.
The burst signal was seen by the all CGBM instruments.  This GRB is also
clearly seen by the publicly available INTEGRAL SPI-ACS light curve.

The light curve of the SGM shows a FRED-like structure.  The emission
starts at T+1.5 sec, peaks at T+5 sec and ends at T+15 sec.  The T90 and
the T50 durations measured by the SGM data are 11.7 +- 2.1 sec and
4.0 +- 1.1 sec (40-1000 keV), respectively.

The ground processed light curve is available at

http://cgbm.calet.jp/cgbm_trigger/ground/1198631204/

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