GCN Circular 23340
Subject
Search for counterparts to IceCube-181014A with IceCube
Date
2018-10-15T17:58:24Z (6 years ago)
From
Alex Pizzuto at ICECUBE/U of Wisconsin <pizzuto@wisc.edu>
The IceCube Collaboration (http://icecube.wisc.edu/) reports:
IceCube has performed a search for additional track-like muon neutrino events arriving from the direction of the IceCube-181014A alert (https://gcn.gsfc.nasa.gov/gcn3/23338.gcn3) in a time range of 2 days centered on the alert event time (2018-10-13 11:52:46 UTC to 2018-10-15 11:52:46 UTC) during which IceCube was collecting good quality data. Excluding the event that prompted the alert, two additional track-like events are found in spatial coincidence with the 90% PSF containment of IceCube-181014A. We find that these data are well described by atmospheric background expectations, with a p-value of 1.0. Accordingly, these tracks would represent a time-integrated muon-neutrino flux upper limit assuming an E^-2 spectrum (E^2 dN/dE) at the 90% CL of 5.59 x 10^-4 TeV cm^-2 for this observation period.
A subsequent search was performed to include the previous month of data (2018-09-14 11:52:46 UTC to 2018-10-15 11:52:46 UTC). In this case, we also report a p-value of 1.0, consistent with no significant excess of track events, and a corresponding time-integrated muon-neutrino flux upper limit assuming an E^-2 spectrum (E^2 dN/dE) at the 90% CL of 1.21 x 10^-1 TeV cm^-2.
The IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica. The IceCube realtime alert point of contact can be reached at roc@icecube.wisc.edu<mailto:roc@icecube.wisc.edu>.
[GCN OPS NOTE(16oct18): Per author's request, the "two additional neutrino track events are found in spatial coincidence with..."
was changed to "two additional track-like events are found in spatial coincidence with...".]