TITLE: GCN CIRCULAR NUMBER: 26237 SUBJECT: LIGO/Virgo S191110af: Upper limits from CALET observations. DATE: 19/11/12 06:43:47 GMT FROM: Yuta Kawakubo at Louisiana State U./CALET S. Torii (Waseda U), A. Yoshida, T. Sakamoto, V. Pal'shin, S. Sugita (AGU), Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN), Y. Asaoka (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 S191110af, T0 = 2019-11-10 23:06:44.183 UT (The LIGO Scientific Collaboration and Virgo Collaboration, GCN Circ. 26222), the CALET Gamma-ray Burst Monitor (CGBM) high voltages were off (from T0-1 min to T0+31 min). The CALET Calorimeter (CAL) was operating in the high energy trigger mode at the trigger time of S191110af. 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 8.4x10^-6 erg/cm^2/s (10-100 GeV) when the summed LIGO-Virgo probability reaches 40%. The CAL FOV was centered at RA= 218.6 deg, DEC= -42.7 deg at T0.