GCN Circular 27791
Subject
IceCube-200523A: Upper limits from Fermi-GBM Observations
Date
2020-05-23T16:57:34Z (5 years ago)
From
Joshua Wood at MSFC/Fermi-GBM <joshua.r.wood@nasa.gov>
J. Wood (NASA/MSFC) reports on behalf of the Fermi-GBM team:
For the IceCube high-energy neutrino candidate event IceCube-200523A
(GCN 27787), at the event time Fermi-GBM was observing the reported
neutrino location at:
RA: 338.64 (+10.77 -6.07 deg 90% PSF containment) J2000
Dee: 1.75 (+1.84 -3.54 deg 90% PSF containment) J2000
There was no Fermi-GBM onboard trigger around the event time of the
neutrino candidate. An automated, blind search for short gamma-ray
bursts below the onboard triggering threshold in Fermi-GBM also
identified no counterpart candidates. The GBM targeted search,
the most sensitive, coherent search for GRB-like signals,
was run from +/-30 s around the neutrino candidate time.
From this search, no significant signal was found related
to IceCube-200523A.
We set upper limits on impulsive gamma-ray emission. Using the
representative soft, normal, and hard GRB-like templates described in
arXiv:1612.02395, we set the following 3 sigma flux upper limits over
10-1000 keV (in units of 10^-7 erg/s/cm^2):
Timescale Soft Normal Hard
-------------------------------------------
0.128 s: 6.5 9.5 17.
1.024 s: 2.2 2.9 6.1
8.192 s: 0.9 1.3 1.8
These results are preliminary.