GCN Circular 19487

Y. Kawakubo, A. Yoshida, T. Sakamoto, M. Moriyama, Y. Yamada (AGU), 
K. Yamaoka (Nagoya U), S. Nakahira (JAXA), 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) 
P. S. Marrocchesi (U of Siena) and the CALET collaboration:

The long-duration GRB 160530B (Fermi-GBM trigger #486316875; Konus-Wind trigger time on 
16:01:13.14 UT) triggered the CALET Gamma-Ray Burst Monitor (CGBM) at 16:01:14.40 on 
30 May 2016.  No real time CGBM GCN notice was distributed about this trigger because 
the real time communication from the ISS was off (loss of signal) between 15:48 and 16:04.  
The burst signal was seen by all CGBM instruments.  

The light curve of the SGM shows bright structure overlaid with multiple spikes.  The emission 
starts at T0-4 sec and ends at T0+16 sec.  The multiple spikes peak at T0+2 sec, T0+3 sec 
and T0+5 sec.  The T90 duration measured by the SGM data is 7.6 +- 0.3 sec (40-450 keV).  
The light curve is available at 

http://cgbm.calet.jp/cgbm_trigger/flight/1148659270/

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