{
  "bibcode": "2017GCN.20861....1B",
  "body": "I. Bartos, S. Countryman (Columbia), C. Finley (U Stockholm), E. Blaufuss (U Maryland), R. Corley, Z. Marka, S. Marka (Columbia) on behalf of the IceCube Collaboration\n\nWe searched IceCube online track-like neutrino candidates (GFU) detected in a [-500,500] second interval about the LIGO-Virgo trigger G277583.  We compared the candidate source directions of 2 temporally-coincident neutrinos to the SKYPROBCC_CWB skymap, with the following parameters:\n\n#            dt[s]     RA[deg]    Dec[deg]      E[TeV]  Sigma[deg]\n------------------------------------------------------------------\n1.         -333.80       161.5        27.6        1.33         1.3\n2.          156.93       207.9        32.0        0.75         0.4\n\n\n(dt--time from GW in [seconds]; RA/Dec--sky location in [degrees]; E--reconstructed secondary muon energy in [TeV]; Sigma--uncertainty of direction reconstruction in [degrees])\n\nThe analysis found NO COINCIDENT ONLINE TRACK-LIKE NEUTRINO CANDIDATES detected by IceCube within the 500 second window surrounding G277583 within the SKYPROBCC_CWB skymap.\n\nIn addition, we are performing coincident searches with other IceCube data streams, including the high-energy starting events (HESE) and Supernova triggers.  HESE events have typical energies > 60 TeV and start inside the detector volume, leading to a relatively pure event sample with a high fraction of astrophysical neutrinos.  The SN trigger system is sensitive to sudden increases in photomultiplier counts across the detector, which could indicate a burst of MeV neutrinos.  We will submit separate GCN circulars if coincident HESE or SN triggers are found.\n\nThe IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica.  For a description of the IceCube realtime alert system, please refer to<http://adsabs.harvard.edu/cgi-bin/bib_query?arXiv:1610.01814>; for more information on joint neutrino and gravitational wave searches, please refer to<http://adsabs.harvard.edu/cgi-bin/bib_query?arXiv:1602.05411>.",
  "circularId": 20861,
  "createdOn": 1489450645000,
  "email": "imrebartos@gmail.com",
  "subject": "LIGO/Virgo G277583: IceCube neutrino observations",
  "submitter": "Imre Bartos at Columbia/LIGO  <imrebartos@gmail.com>",
  "eventId": "LIGO/Virgo G277583"
}