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GCN Circular 24960

Subject
LIGO/Virgo S190630ag: Upper limits from CALET observations
Date
2019-07-02T02:33:59Z (5 years ago)
From
Yuta Kawakubo at Louisiana State U./CALET <kawakubo1@lsu.edu>
M. L. Cherry (LSU), 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),
Y. Shimizu, T. Tamura (Kanagawa U), N. Cannady (GSFC/UMBC), 
S. Ricciarini (U of Florence), P. S. Marrocchesi (U of Siena),
and the CALET collaboration:

At the trigger time of the compact binary merger candidate S190630ag,
T0 = 2019-06-30 18:52:05.180 UT (The LIGO Scientific Collaboration 
and Virgo Collaboration, GCN Circ. 24922), the CALET Gamma-ray 
Burst Monitor (CGBM) high voltages were off (from T0-15 min to 
T0+0.5 min).

The CALET Calorimeter (CAL) was operating in the high energy
trigger mode at the trigger time of S190630ag. Using the CAL data,
we have searched for gamma-ray events in the 10-100 GeV
band from -60 sec to +60 sec from the GW trigger time and
found no candidates.
The 90% upper limit of CAL is 1.2x10^-5 erg/cm^2/s (10-100 GeV) when
the summed LIGO-Virgo probability reaches 25%.
The CAL FOV was centered at RA= 84.0 deg, DEC= 31.5 deg at T0.
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