[vsnet-grb-info 23305] IceCube-190819A: Upper limits from Fermi-GBM Observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  25404
SUBJECT: IceCube-190819A: Upper limits from Fermi-GBM Observations
DATE:    19/08/19 22:59:26 GMT
FROM:    Joshua Wood at MSFC/Fermi-GBM  <joshua.r.wood at nasa.gov>

J. Wood, M. Hui, and D. Kocevski (NASA/MSFC) report on behalf of the Fermi-GBM Team:

For the IceCube high-energy neutrino candidate event 190819A (GCN 25402), at the event time Fermi-GBM was observing the reported neutrino location at:

RA: 148.80 (+2.07 -3.24 deg  90% PSF containment) J2000
Dec: 1.38 (+1.00 -0.75 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-190819A.

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:   4.1      5.9      12.
1.024 s:   1.5      2.1      4.6
8.192 s:   0.5      0.9      1.5