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GCN Circular 26761

Subject
LIGO/Virgo S200114f: Upper limits from CALET observations.
Date
2020-01-15T06:27:32Z (5 years ago)
From
Yuta Kawakubo at Louisiana State U./CALET <kawakubo1@lsu.edu>
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. 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:

At the trigger time of the compact binary merger candidate 
S200114f T0 = 2020-01-14 02:08:18.239 UT (The LIGO 
Scientific Collaboration and Virgo Collaboration, GCN 
Circ. 26734), the CALET Gamma-ray Burst Monitor (CGBM)
high voltages were off (from T0-4 min to T0+4 min).

The CALET Calorimeter (CAL) was operating in the high 
energy trigger mode at the trigger time of S200114f. 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 in the overwrap region with the
LIGO-Virgo high probability localization region.  The 90% upper
limit of CAL is 4.7 x 10^-6 erg/cm^2/s (10-100 GeV) when the
summed LIGO-Virgo probability reaches 80%. The CAL FOV
was centered at RA= 111.2 deg, DEC= +50.7 deg at T0.
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