GCN Circular 34427
Subject
GRB 230812B: Upper limits from a neutrino search with IceCube
Date
2023-08-14T22:45:46Z (2 years ago)
From
Jessie Thwaites at IceCube/U Wisc-Madison <thwaites@wisc.edu>
Via
Web form
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 230812B (GCN Circular 34391 (Fermi-GBM), 34392 (Fermi-LAT)) at the position determined by Swift-XRT (GCN Circular 34394) in a time range of -1 hour/+2 hours from the initial trigger reported by Fermi-GBM (T0=2023-08-12 18:58:12.05 UTC) during which IceCube was collecting good quality data.
Zero track-like events are found to coincide 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 = 5.1 x 10^-2 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 600 GeV and 300 TeV.
A subsequent search was performed including 2 days of data centered on the Fermi-GBM trigger (2023-08-11 18:58:12.05 UTC to 2023-08-13 18:58:12.05 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 = 5.4 x 10^-2 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.
[1] IceCube Collaboration, R. Abbasi et al., ApJ 910 4 (2021)