TITLE:   GCN CIRCULAR
NUMBER:  24406
SUBJECT: GRB 190501A: CALET Gamma-Ray Burst Monitor detection
DATE:    19/05/06 11:11:48 GMT
FROM:    Valentin Pal'shin at AGU  <val@phys.aoyama.ac.jp>

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

The long bright GRB 190501A (AGILE/MCAL detection: Ursi et al.,
GCN Circ. 24360; AGILE/GRID detection and localization: Lucarelli et al.,
GCN Circ. 24361, Verrecchia et al. GCN Circ. 24363;
IPN triangulation: Hurley et al., GCN Circ. 24372)
triggered the CALET Gamma-ray Burst Monitor (CGBM) at 05:23:17.604 UTC
on 1 May 2019. The burst signal was seen by all CGBM detectors.

The burst light curve shows a multi-peaked structure which starts at
T=1.9 sec, peaks at 6.0 sec and ends at T+27.4 sec.
The T90 and T50 durations measured by the SGM data are 15.5 +- 3.5 sec
and 6.8 +- 0.6 sec (40-1000 keV), respectively.

The ground processed light curve is available at

http://cgbm.calet.jp/cgbm_trigger/ground/1240723364/

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