TITLE:   GCN CIRCULAR
NUMBER:  34593
SUBJECT: GRB 230827B: CALET Gamma-Ray Burst Monitor detection
DATE:    23/08/29 15:56:27 GMT
FROM:    Yuta Kawakubo at Louisiana State University <kawakubo1@lsu.edu>

T. Tamura (Kanagawa U), A. Yoshida, T. Sakamoto, S. Sugita (AGU), 
Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (JAXA),
Y. Asaoka (ICRR), S. Torii, Y. Akaike, K. Kobayashi (Waseda U),
Y. Shimizu (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 GRB 230827B (Fermi GBM Observation: Hamburg et al.,
GCN Circ. 34584; VZLUSAT-2 detection: Dafcikova et al., GCN 
Circ. 34585) triggered the CALET Gamma-ray Burst Monitor (CGBM)
at 06:08:28.36 UTC on 27 July 2023
(http://cgbm.calet.jp/cgbm_trigger/flight/1377151581/).
The burst signal was seen by only the SGM detector.

The burst light curve shows a multi-peaked structure that starts
at T+2.3 sec, peaks at T+2.7 sec, and ends at T+87.7 sec.
The T90 and T50 durations measured by the SGM data are 79.6 +/- 3.7 sec
and 57.4 +/- 2.5 sec (40-1000 keV), respectively.

The ground-processed light curve is available at

 http://cgbm.calet.jp/cgbm_trigger/ground/1377151581/

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