TITLE:   GCN CIRCULAR
NUMBER:  33359
SUBJECT: GRB 230216B: CALET Gamma-Ray Burst Monitor detection 
DATE:    23/02/21 04:32:39 GMT
FROM:    Yuta Kawakubo at Louisiana State U./CALET  <kawakubo1@lsu.edu>

Y. Akaike  (Waseda U), A. Yoshida, T. Sakamoto, S. Sugita (AGU),
Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN),
Y. Asaoka (ICRR), S. Torii, K. Kobayashi (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 long GRB 230216B (AstroSat CZTI detection: Shetty et al.,
GCN Circ. 33341) triggered the CALET Gamma-ray Burst Monitor
(CGBM) at 19:03:22.03 UTC on 16 February 2023
(http://cgbm.calet.jp/cgbm_trigger/flight/1360609287/index.html).
The burst signal was seen by all CGBM detectors.

The burst light curve shows a multi-peaked structure that starts
at T+1.5 sec, peaks at T+4.9 sec, and ends at T+11.1 sec.
The T90 and T50 durations measured by the SGM data are 8.3 +/- 1.1 sec
and 3.1 +/- 0.4 sec (40-1000 keV), respectively.

The ground-processed light curve is available at

http://cgbm.calet.jp/cgbm_trigger/ground/1360609287/

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