[vsnet-grb-info 24598] IceCube-200109A: Upper limits from Fermi-GBM Observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  26697
SUBJECT: IceCube-200109A: Upper limits from Fermi-GBM Observations
DATE:    20/01/10 04:44:32 GMT
FROM:    Joshua Wood at MSFC/Fermi-GBM  <joshua.r.wood at nasa.gov>

J. Wood (NASA/MSFC) reports on behalf of the Fermi-GBM team:

For the IceCube high-energy neutrino candidate event 200109A (GCN 26696), at the event time Fermi-GBM was observing the reported neutrino location at:

RA: 164.49 (+4.94 -4.19 deg 90% PSF containment) J2000
Dec: 11.87 (+1.16 -1.36 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-200109A.

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:    7.3      11.      16.
1.024 s:    2.1      2.8      3.6
8.192 s:    0.4      0.6      1.2