GCN Circular 33430
Subject
GRB 230307A: Upper limits from a neutrino search with IceCube
Date
2023-03-09T00:17:46Z (2 years ago)
From
Jessie Thwaites at IceCube/U Wisc-Madison <thwaites@wisc.edu>
The IceCube Collaboration (http://icecube.wisc.edu/) reports:
IceCube has performed a search for track-like muon neutrino events arriving from the direction of GRB 230307A (GCN 33405<https://gcn.gsfc.nasa.gov/gcn/gcn3/33405.gcn3> (Fermi-GBM)) in a time range of -1 hour/+2 hours from the initial trigger reported by Fermi-GBM (2023-03-07 15:44:06.67 UTC), using the localization area reported by IPN (GCN 33425<https://gcn.gsfc.nasa.gov/gcn/gcn3/33425.gcn3>), during which IceCube was collecting good quality data. Zero track-like events are found coincident with the position of the GRB. We accordingly derive a time-integrated muon-neutrino flux upper limit for this source of E^2 dN/ dE = 1.0 GeV 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 90 TeV and 20 PeV.
A subsequent search was performed including 2 days of data centered on the Fermi-GBM trigger (2023-03-06 15:44:06.67 UTC to 2023-03-08 15:44:06.67 UTC). In this case, we report a p-value of 1.0, consistent with background expectation. We accordingly derive a time-integrated muon-neutrino flux upper limit for this source of E^2 dN/ dE = 1.1 GeV cm^-2 at 90% CL, under the assumption of an E^-2 power law.
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>.
[1] IceCube Collaboration, R. Abbasi et al., ApJ 910 4 (2021)