Skip to main content
Testing. You are viewing the public testing version of GCN. For the production version, go to
New Announcement Feature, Code of Conduct, Circular Revisions. See news and announcements

GCN Circular 25246

GRB 190731A: CALET Gamma-Ray Burst Monitor detection
2019-08-01T10:06:20Z (5 years ago)
Valentin Pal'shin at AGU <>
Y. Asaoka (Waseda U),
A. Yoshida, T. Sakamoto, V. Pal'shin, S. Sugita (AGU),
Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN),
S. Ozawa, 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 long bright GRB 190731A (Fermi GBM Final Real-time Localization: Fermi
GBM Team, GCN Circ. 25240; Fermi-LAT detection: Ohno et al., GCN Circ.
25244) triggered the CALET Gamma-ray Burst Monitor (CGBM) at 22:38:18.315
UTC on 31 July 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+3.1 sec, peaks at T+4.4 sec and ends at T+26.0 sec. The T90
and T50 durations measured by the SGM data are 14.6 +- 1.8 sec and
5.0 +- 0.5 sec (40-1000 keV), respectively.

The ground processed light curve is available at

The CALET data used in this analysis are provided by
the Waseda CALET Operation Center located at the Waseda University.
Looking for U.S. government information and services? Visit