[vsnet-grb-info 21940] Search for additional neutrino events from the direction of IceCube-190331A with IceCube

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  24039
SUBJECT: Search for additional neutrino events from the direction of IceCube-190331A with IceCube
DATE:    19/04/01 16:26:27 GMT
FROM:    Alex Pizzuto at ICECUBE/U of Wisconsin  <pizzuto at 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-190331A (https://gcn.gsfc.nasa.gov/gcn3/24028.gcn3) in a time
range of 2 days centered on the alert event time (2019-03-30 06:55:43.44 UTC to 2019-04-01
06:55:43.44 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% PSF containment of IceCube-190331A. We find that these data are well described
by atmospheric background expectations, with a p-value of 1.0. Accordingly, these data would
represent a time-integrated muon-neutrino flux upper limit assuming an E^-2 spectrum (E^2
dN/dE) at the 90% CL of 3.0 x 10^-4 TeV cm^-2 for this observation period. 90% of events
IceCube would detect from a source at this declination with an E^-2 spectrum are between
approximately 10 TeV and 1 PeV.

A subsequent search was performed to include the previous month of data (2019-03-01 06:55:43.44 UTC to 2019-04-01 06:55:43.44 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
3.8 x 10^-4 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 at icecube.wisc.edu<mailto:roc at icecube.wisc.edu>