[vsnet-grb-info 20265] GRB 180116A CALET Gamma-Ray Burst Monitor detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  22361
SUBJECT: GRB 180116A CALET Gamma-Ray Burst Monitor detection
DATE:    18/01/18 14:31:46 GMT
FROM:    Takanori Sakamoto at AGU  <tsakamoto at phys.aoyama.ac.jp>

Y. Shimizu (Kanagawa U), 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), I. Takahashi (IPMU), Y. Asaoka, S. Ozawa, S. Torii (Waseda U),
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, soft and weak GRB 180116A (Kawai et al., GCN circ. 22347;
Stanbro et al., GCN circ. 22356) was detected by the CALET Gamma-ray Burst
Monitor (CGBM) in the survey mode.  The burst signal is only seen below 100 keV
in all CGBM instruments, confirming its soft nature.

The light curve of the HXM shows several overlapping pulses.  The emission
starts at T-5 sec, peaks at T+11 sec and ends at T+47 sec, where T0 is the
Fermi-GBM trigger time at 00:36:52.81 UT.  The T90 and the T50 durations
measured by the combined HXM data (HXM1+HXM2) are 46 +- 10 sec and
27 +- 10 sec (10-300 keV), respectively.

The ground processed light curve is available at

http://cgbm.calet.jp/cgbm_trigger/ground/1200098002/

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