{
  "bibcode": "2016GCN.20122....1S",
  "body": "V. Savchenko (APC, Paris, France) , C. Ferrigno (ISDC, University of\nGeneva, CH), P. Ubertini, A. Bazzano, L. Natalucci (INAF IAPS-Roma,\nItaly), S. Mereghetti (INAF IASF-Milano, Italy), P. Laurent (CEA,\nSaclay, France), E. Kuulkers (ESAC/ESA, Madrid, Spain)\n\nUsing INTEGRAL SPI-ACS and IBIS/Veto we have performed a search for a\nprompt gamma-ray counterpart of the cosmic neutrino candidate IceCube-161103 (GCN 20119).\n\nAt the time of the event (2016-11-03 09:07:31.12 UTC, hereafter T0),\nINTEGRAL was operating in the nominal mode. The spacecraft was\npointing in the direction of GRS 1915+105, and the neutrino localization\nwas at an angle of 113 deg with respect to the pointing axis.\nThis orientation implies moderately suppressed response of both SPI-ACS\nand IBIS/Veto, with the best limit provided by SPI-ACS for every considered\nspectrum for the sources in the 90% PSF containment of IceCube localization.\n\nThe background within +/-300 seconds around the event was very stable.\nHowever, 90 seconds after T0 INTEGRAL/SPI-ACS detected a short excess\nin a single bin (50 ms), consistent with the properties of the excesses\nproduced in SPI-ACS by cosmic ray interactions.\nProbability of a cosmic ray effect with these properties happening within\nthe given search time window is 25%.\n\nWe estimate a 3-sigma upper limit on the 75-2000 keV fluence of\n4.6x10^-7 erg/cm^2 for a burst lasting less than 1 s with a\ncharacteristic short GRB spectrum (an exponentially cut off power law\nwith alpha=-0.5 and Ep=500 keV) occurring at any time in the\ninterval +/-300 s around T0.\n\nFor a typical long GRB spectrum (Band function with alpha=-1, beta=-2.5,\nand Ep=250 keV), the derived peak flux upper limit is ~4.3x10^-7 (1.1x10^-6)\nerg/cm^2/s at 1 s (8 s) time scale in 75-2000 keV energy range.\n\nWe also set an upper limit on the peak flux on 8 s time scale  with IBIS/Veto\nat the level of 1.9x10^-6 erg/cm^2/s in 75-2000 keV energy range.\n\nNo pointed INTEGRAL observations of the location of IceCube-161103 have been\nperformed or planned.",
  "circularId": 20122,
  "createdOn": 1478250217000,
  "email": "savchenk@in2p3.fr",
  "subject": "INTEGRAL SPI-ACS and IBIS/Veto observation of IceCube-161103",
  "submitter": "Volodymyr Savchenko at ISDC,U of Geneve  <savchenk@in2p3.fr>"
}