GCN Circular 25808
Subject
IceCube-190922B: Upper limits from Fermi-GBM Observations
Date
2019-09-23T05:51:18Z (5 years ago)
From
Eric Burns at GSFC <erickayserburns@gmail.com>
E. Burns (NASA/GSFC) reports on behalf of the Fermi-GBM Team:
For the IceCube high-energy neutrino candidate event 190922B (GCN 25806),
at the event time Fermi-GBM was observing the reported neutrino location at:
RA: 5.76 (+ 1.19 - 1.37 deg 90% PSF containment) J2000
Dec: -1.57(+ 0.93 - 0.82 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-190922B.
We set upper limits on impulsive gamma-ray emission. Using the
representative soft, normal, and hard GRB-like templates
(arXiv:1612.02395), we report the following 3 sigma flux upper limits over
10-1000 keV (in units of 10^-7 erg/s/cm^2):
Timescale soft norm hard
--------------------------------------
0.128 s: 2.9 5.2 11.
1.024 s: 0.8 1.5 2.7
8.192 s: 0.3 0.6 1.1