[vsnet-grb-info 26417] IceCube-200926B: No neutrino counterpart candidates in ANTARES search

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  28517
SUBJECT: IceCube-200926B: No neutrino counterpart candidates in ANTARES search
DATE:    20/09/27 22:39:09 GMT
FROM:    Antoine Kouchner at ANTARES Collaboration  <kouchner at apc.in2p3.fr>

Alexis Coleiro (APC/Universite de Paris) and Damien Dornic (CPPM/CNRS) on behalf of the ANTARES Collaboration.

Using data from the ANTARES detector, we have performed a follow-up analysis of the recently reported single track-like event IceCube-200926B (GCN 28509 <https://gcn.gsfc.nasa.gov/gcn3/28509.gcn3>). The reconstructed origin was -13.3 degrees below the horizon for ANTARES.

No up-going muon neutrino candidate events were recorded within the 90% error box of the IceCube event during a +/- 1h time-window centered on the IceCube event time, and over which the potential source remained visible all time. This leads to a preliminary 90% confidence level upper limit on the muon-neutrino fluence from a point source of 15.5 GeV.cm^-2 over the energy range 8 TeV - 7 PeV (the range corresponding to 5-95% of the detectable flux) for an E^-2 power-law spectrum, and 35.5 GeV.cm^-2 (1 - 690 TeV) for an E^-2.5 spectrum. A search over an extended time window of +/- 1 day has also yielded no detection (29% visibility). 

 ANTARES <http://antares.in2p3.fr/> is the largest undersea neutrino detector (Mediterranean Sea) and it is primarily sensitive to astrophysical neutrinos in the TeV-PeV energy range. At 10 TeV, the median angular resolution for muon neutrinos is about 0.5 degrees. In the range 1-100 TeV ANTARES has a competitive sensitivity to this position in the sky.