TITLE:   GCN CIRCULAR
NUMBER:  27911
SUBJECT: GRB 200605A: CALET Gamma-Ray Burst Monitor detection
DATE:    20/06/09 11:11:36 GMT
FROM:    Valentin Pal'shin at AGU  <val@phys.aoyama.ac.jp>

Y. Kawakubo (LSU),
A. Yoshida, T. Sakamoto, V. Pal'shin, S. Sugita (AGU),
K. Yamaoka (Nagoya U), S. Nakahira (RIKEN),
Y. Asaoka, S. Torii (Waseda U), Y. Shimizu, 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 short GRB 200605A (Fermi GBM Localization: the Fermi GBM team,
GCN Circ. 27892; IPN triangulation: Hurley et al., GCN Circ. 27900;
https://gcn.gsfc.nasa.gov/other/200605A.gcn3)
triggered the CALET Gamma-ray Burst Monitor (CGBM) at 18:17:42.317 UTC
on 5 June 2020. The burst signal was seen by only the SGM detector.
The source location was outside the FOV of the HXM detectors.
Because of a problem in one of the ground alert processing script,
the GCN notice was not distributed automatically for this event.

The burst light curve shows a double-peaked pulse which starts at
T-0.176 sec, peaks at -0.048 sec and ends at T+0.256 sec. The T90 and T50
durations measured by the SGM data are 0.368 +- 0.062 sec and
0.232 +- 0.051 sec (40-1000 keV), respectively.

The ground processed light curve is available at

http://cgbm.calet.jp/cgbm_trigger/ground/1275416255/

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