Difference: GCNCIRCULAR20739 ( vs. 1)

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

We searched IceCube online track-like neutrino candidates (GFU) detected in a [-500,500] second interval about the LIGO-Virgo trigger G275404. We compared the candidate source directions of 3 temporally-coincident neutrinos to the pyCBC skymap, with the following parameters:

# dt[s] RA[deg] Dec[deg] E[TeV] Sigma[deg]

(dt-time from GW; RA,Dec-sky location; E-reconstructed energy; Sigma-uncertainty of direction reconstruction)

The analysis found NO COINCIDENT ONLINE TRACK-LIKE NEUTRINO CANDIDATES detected by IceCube within the 500 second window surrounding G275404 within the BAYESTAR skymap.

In 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.

The 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>.

-- ThomasKupfer - 27 Feb 2017