GCN Circular 30346
Subject
IceCube-210629A: Upper limits from Fermi-GBM Observations
Event
Date
2021-06-30T17:11:47Z (4 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-210629A (GCN 30342),
at the event time Fermi-GBM was observing the reported neutrino location at:
RA: 340.75 (+1.11 -2.23 deg 90% PSF containment) J2000
Dec: +12.94 (+0.91 -0.93 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-210629A.
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 Normal Hard
--------------------------------------
0.128 s: 5.2 8.3 18.
1.024 s: 1.3 2.4 5.0
8.192 s: 0.5 0.9 1.8
These results are preliminary.