TITLE:   GCN CIRCULAR
NUMBER:  25148
SUBJECT: GRB 190720A: CALET Gamma-Ray Burst Monitor detection
DATE:    19/07/25 05:57:30 GMT
FROM:    Valentin Pal'shin at AGU  <val@phys.aoyama.ac.jp>

Y. Kawakubo (LSU),
A. Yoshida, T. Sakamoto, V. Pal'shin, S. Sugita (AGU),
K. Yamaoka (Nagoya U), S. Nakahira (RIKEN),
Y. Asaoka, 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 190720A (Fermi GBM detection: Hui and Meegan,
GCN Circ. 25131; BALROG localization: Kunzweiler et al., GCN Circ. 25124;
IPN triangulation: Hurley et al., GCN Circ. 25139) triggered the CALET
Gamma-ray Burst Monitor (CGBM) at 14:42:10.000 UTC on 20 July 2019.
The burst signal was seen by all CGBM detectors.
No real-time CGBM GCN notice was distributed about this trigger because
the real-time communication from the ISS was off (loss of signal).

The burst light curve shows a single multi-peaked pulse which starts
at T-0.2 sec, peaks at 2.4 sec and ends at T+14.0 sec. The T90 and T50
durations measured by the SGM data are 5.9 +- 1.0 sec and 2.1 +- 0.2 sec
(40-1000 keV), respectively.

The ground processed light curve is available at

http://cgbm.calet.jp/cgbm_trigger/ground/1247668851/

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