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GCN Circular 28142

AMON IC_HAWC 170720: No Neutrino Counterpart detected with ANTARES
2020-07-18T21:29:17Z (4 years ago)
Antoine Kouchner at ANTARES Collaboration <>
Alexis Coleiro (APC/Univ de Paris) and Damien Dornic (CPPM/CNRS) on behalf of the ANTARES Collaboration. <br>

Using data from the ANTARES detector, we have performed a follow-up analysis of the recently reported AMON IC-HAWC coincidence alert (Notice <>). <br>

No up-going muon neutrino candidate events were detected within 3 degrees from the coincidence coordinates over a time period [17h40 - 21h22 UTC] corresponding to 69% of the ���delta_t" interval before the ���discovery_time" mentioned in the AMON notice, during which the potential source remained visible in the up-going field of view of ANTARES. <br>

This leads to a preliminary 90% confidence level upper limit on the muon neutrino radiant fluence from a point source located at the coordinates of the coincidence as reported by AMON, of about 15^-2 over the energy range 3TeV ��� 3.4PeV (the range corresponding to 5-95% of the detectable flux) for an E^-2 power-law spectrum, and about 25^-2 (595 GeV - 310TeV) for an E^-2.5 spectrum. These indicative limits have been computed for the ���discovery_time��� given in the notice. <br>

A search over an extended time window of +/-1 day has also yielded no detection (50% visibility). <br>

ANTARES 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.

[GCN OPS NOTE(19jul20):  Please note GCN Circular 28144 from the same author about the accidental inclusion of the URL: <> in this Circular 28142 -- it should not have been included in this Circular 28142.]
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