LIGO/Virgo S190720a: Upper limits from CALET observations
Abstract
At the trigger time of the compact binary merger candidate S190720a, T0 = 2019-07-20 00:08:36.704 UT (The LIGO Scientific Collaboration and Virgo Collaboration, GCN Circ. 25115), the CALET Gamma-ray Burst Monitor (CGBM) high voltages were off (from T0-4 min to T0+17 min). The CALET Calorimeter (CAL) was operating in the high energy trigger mode at the trigger time of S190720a. 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 3.0x10^-5 erg/cm^2/s (10-100 GeV) when the summed LIGO-Virgo probability reaches 25%. The CAL FOV was centered at RA = 49.7 deg and DEC = -32.1 deg at T0.
- Publication:
-
GRB Coordinates Network
- Pub Date:
- July 2019
- Bibcode:
- 2019GCN.25134....1S