TITLE:   GCN CIRCULAR
NUMBER:  28357
SUBJECT: GRB 200903A: CALET Gamma-Ray Burst Monitor detection
DATE:    20/09/03 12:06:27 GMT
FROM:    Valentin Pal'shin at AGU  <val@phys.aoyama.ac.jp>

Y. Shimizu (Kanagawa U),
A. Yoshida, T. Sakamoto, V. Pal'shin, S. Sugita (AGU),
Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN),
Y. Asaoka (ICRR), S. Torii, Y. Akaike, K. Kobayashi (Waseda U),
T. Tamura (Kanagawa U), N. Cannady (GSFC/UMBC), M. L. Cherry (LSU),
S. Ricciarini (U of Florence), P. S. Marrocchesi (U of Siena),
and the CALET collaboration:

The long soft GRB 200903A (Swift detection: Beardmore et al.,
GCN Circ. 28350; https://gcn.gsfc.nasa.gov/other/200903A.gcn3)
triggered the CALET Gamma-ray Burst Monitor (CGBM) at 00:44:17.477 UTC
on 3 September 2020 (http://cgbm.calet.jp/cgbm_trigger/flight/1283129005/).
The burst signal was seen by all CGBM detectors.

The burst light curve shows a multi-peaked structure which starts
at T+1.5 sec, peaks at T+5.9 sec, and ends at T+10.5 sec.
The T90 and T50 durations measured by the SGM data are 8.2 +- 0.8 sec
and 4.2 +- 0.8 sec (40-1000 keV), respectively.

The ground processed light curve is available at

http://cgbm.calet.jp/cgbm_trigger/ground/1283129005/

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