[vsnet-grb-info 19162] GRB 170228B CALET Gamma-Ray Burst Monitor detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  20803
SUBJECT: GRB 170228B CALET Gamma-Ray Burst Monitor detection
DATE:    17/03/03 06:13:49 GMT
FROM:    Takanori Sakamoto at AGU  <tsakamoto at phys.aoyama.ac.jp>

P. S. Marrocchesi (U of Siena)  A. Yoshida, T. Sakamoto, Y. Kawakubo,
M. Moriyama, Y. Yamada (AGU), K. Yamaoka (Nagoya U), S. Nakahira (JAXA),
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),
and the CALET collaboration:

The long-duration GRB 170228B (Fermi GBM trigger #509999585;
Xiao et al, GCN Circ. 20792) triggered the CALET Gamma-ray Burst
Monitor (CGBM) at 18:32:58.03 on 28 February 2017.  The burst signal
was seen by the HXM2 and SGM instrument.

The light curve of the SGM shows two peaks.  The first peak starts at T0,
peaks at T+5 sec and ends at T+18 sec.  The second peak starts at T+20 sec,
peaks at T+25 sec and ends at T+35 sec.  The T90 duration measured by
the SGM data is 32.2 +- 1.2 sec (40-1000 keV).

The light curve is available at

http://cgbm.calet.jp/cgbm_trigger/flight/1172341676/

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