GCN Circular 31560
Subject
IceCube-220205B: Upper limits from a search for additional neutrino events in IceCube
Date
2022-02-07T20:53:35Z (3 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 IceCube-220205B (https://gcn.gsfc.nasa.gov/gcn3/31554.gcn3) in a time
range of 1000 seconds centered on the alert event time (2022-02-05 19:59:50.59 UTC to 2022-02-05 20:16:30.59 UTC) during which IceCube was collecting good quality data. Excluding the event that prompted the alert, zero additional track-like events are found in spatial coincidence with the 90% containment region of IceCube-220205B. We accordingly derive a time-integrated muon-neutrino flux upper limit at the alert position of E^2 dN/dE = 3.1 x 10^-5 TeV cm^-2 at 90% CL, under the assumption of an E^-2 power law. 90% of events IceCube would detect from a source at this declination with an E^-2 spectrum have energies in the approximate energy range between 2 TeV and 7 PeV.
A subsequent search was performed including 2 days of data centered on the alert event time (2022-02-04 20:08:10.59 UTC to 2022-02-06 20:08:10.59 UTC). In this case, we report a p-value of 0.03, consistent with no significant excess of track-like events, and a corresponding time-integrated muon-neutrino flux upper limit assuming an E^-2 spectrum (E^2 dN/dE) of
4.2 x 10^-5 TeV cm^-2 at the 90% CL.
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>.