[vsnet-grb-info 21955] GRB 190404B: CALET Gamma-Ray Burst Monitor detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  24055
SUBJECT: GRB 190404B: CALET Gamma-Ray Burst Monitor detection
DATE:    19/04/05 23:02:04 GMT
FROM:    Valentin Pal'shin at AGU  <val at phys.aoyama.ac.jp>

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

The long GRB 190404B (MAXI/GSC detection: Nakajima et al., GCN Circ. 24048)
was detected in ground analysis of the CALET Gamma-ray Burst Monitor (CGBM)
data near the MAXI trigger time at T0=12:24:20 UTC on 4 April 2019.
The burst signal was seen by all CGBM detectors.

The burst light curve shows a single multi-peaked emission episode
which starts at T-15.1 sec and ends at T+80.4 sec.
The T90 and the T50 durations measured by the SGM data are
87.5 +- 18.8 sec and 47.6 +- 17.5 sec (40-1000 keV), respectively.

The ground processed light curve is available at

http://cgbm.calet.jp/cgbm_trigger/ground/1238415870/

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