[vsnet-grb-info 22871] LIGO/Virgo S190701ah: No transient candidates from CALET observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  24970
SUBJECT: LIGO/Virgo S190701ah: No transient candidates from CALET observations
DATE:    19/07/03 03:00:41 GMT
FROM:    Yuta Kawakubo at Louisiana State U./CALET  <kawakubo1 at lsu.edu>

S. Ricciarini (U of Florence) 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), 
M. L. Cherry (LSU), P. S. Marrocchesi (U of Siena),
and the CALET collaboration:

The CALET Gamma-ray Burst Monitor (CGBM) was operating at the
trigger time of S190701ah T0 = 2019-07-01 20:33:06.578 UT (The
LIGO Scientific Collaboration and Virgo Collaboration, GCN Circ. 
24950).

No CGBM on-board trigger occurred around the event time.  Based
on the LIGO-Virgo localization sky map, the high probability area 
was outside of the CGBM field of view.  The summed LIGO probabilities 
inside the CGBM HXM (7-3000 keV) and SGM (40 keV - 28 MeV) fields
of view are 0% (and 30% credible region of the initial localization map
was above the horizon).  The HXM and SGM fields of view were centered
at RA = 278.6 deg, Dec = 4.1 deg and  RA = 286.9 deg, Dec = -1.6 deg at
T0, respectively.

Based on the analysis of the light curve data with 0.125 sec time 
resolution from T0-60 sec to T0+60 sec, we found no significant excess 
(signal-to-noise ratio >= 7) around the trigger time in either the HXM or 
the SGM data.

The CALET Calorimeter (CAL) was operating in the low energy
trigger mode at the trigger time of S190701ah, but the CAL FOV 
does not have any overlap with the LVC high probability localization 
region.　
The CAL FOV was centered at RA= 286.8 deg, DEC= -1.6 deg at T0.