{
  "bibcode": "2023GCN.33872....1Y",
  "createdOn": 1684996750525,
  "submitter": "Yuta Kawakubo at Louisiana State University <kawakubo1@lsu.edu>",
  "eventId": "LIGO/Virgo/KAGRA S230518h",
  "body": "A. Yoshida, T. Sakamoto, S. Sugita (AGU), Y. Kawakubo (LSU),\nK. Yamaoka (Nagoya U), S. Nakahira (JAXA), Y. Asaoka (ICRR),\nS. Torii, Y. Akaike, K. Kobayashi (Waseda U), Y. Shimizu, \nT. Tamura (Kanagawa U), N. Cannady (GSFC/UMBC),\nM. L. Cherry (LSU), S. Ricciarini (U of Florence),\nP. S. Marrocchesi (U of Siena),\nand the CALET collaboration:\n\nThe CALET Gamma-ray Burst Monitor (CGBM) was operating at the trigger\ntime of S230518h T0 = 2023-05-18T12:59:08 UT (GCN33813,33816).\n\nNo CGBM onboard trigger occurred around the event time. Based on the\nupdate sky map, the summed probabilities inside the CGBM HXM (7 - 3000 keV)\nand SGM (40 keV - 28 MeV) fields of view\nare 0 % and 65 %, respectively (and 76 % credible regions of the\nupdate sky map was above the horizon).  The HXM and SGM fields of\nview were centered at RA = 152 deg, Dec = +50 deg and RA = 161 \ndeg, Dec = +42 deg at T0, respectively.\n\nBased on the analysis of the light curve data with 0.125 sec time \nresolution from T0-60 sec to T0+60 sec, we found no significant \nexcess (> 7 sigmas) around the trigger time in either the HXM or the SGM data.\n\nThe preliminary CGBM analysis is available at\n\nhttp://cgbm.calet.jp/cgbm_trigger/O4/S230518h\n\nThe CALET Calorimeter (CAL) was operating in the high energy trigger\nmode at the trigger time of S230518h. Using the CAL data, we searched \nfor gamma-ray events in the 10-100 GeV band from -60 sec\nto +60 sec from the GW trigger time and found no candidates. There\nwas no significant overlap with the LVK high probability localization \nregion at T0+-60 sec.  The CAL FOV was centered at RA = 161 deg, \nDec= +42 deg at T0.\n\nThe preliminary CGBM analysis for O4 events can be found here:\nhttp://cgbm.calet.jp/cgbm_trigger/O4\n",
  "circularId": 33872,
  "subject": "LIGO/Virgo/KAGRA S230518h: No transient candidates in CALET observations"
}