TITLE:   GCN CIRCULAR
NUMBER:  29475
SUBJECT: IceCube-210210A: No neutrino counterpart in ANTARES
DATE:    21/02/11 12:47:34 GMT
FROM:    Antoine Kouchner at ANTARES Collaboration  <kouchner@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-210210A (GCN #29454 <https://gcn.gsfc.nasa.gov/gcn3/29454.gcn3>). The reconstructed origin was -18 degrees below the horizon for ANTARES.

No up-going muon neutrino candidate events were recorded within 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 16 GeV.cm^-2 over the energy range 3.5 TeV - 3.7 PeV (the range corresponding to 5-95% of the detectable flux) for an E^-2 power-law spectrum, and 40 GeV.cm^-2 (680 GeV - 355 TeV) for an E^-2.5 spectrum. A search over an extended time window of +/- 1 day has also yielded no detection (50% 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.