[vsnet-grb-info 21691] Fermi-LAT Gamma-ray Observations of IceCube-190124A

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  23790
SUBJECT: Fermi-LAT Gamma-ray Observations of IceCube-190124A
DATE:    19/01/24 19:51:29 GMT
FROM:    Sara Buson at GSFC/Fermi  <sara.buson at gmail.com>

S. Buson (Univ. of Wuerzburg, UMBC), R. Angioni (MPIfR-Bonn), S. Garrappa (DESY-Zeuthen), F. Krauss (UvA), M. Kreter (North-West University, Potchefstroom), S. Cutini (Univ. of Perugia), D. Kocevski (NASA/MSFC)  on behalf of the Fermi-LAT collaboration:

We report an analysis of observations of the vicinity of the very high-energy IC190124A neutrino event (GCN 23785) with all-sky survey data from the Large Area Telescope (LAT), on board the Fermi Gamma-ray Space Telescope. The IceCube event was detected on 2019-01-24 03:43:54.79 UTC with J2000 position RA = 307.40 (-0.9,+0.8) deg, Decl. = -32.18 (-0.7,+0.7) deg 90% PSF containment. No catalogued >100 MeV gamma-ray source is found within the 90% IC190124A localization error.
We searched for the existence of intermediate (months to years) timescale emission from a new gamma-ray transient source. Preliminary analysis indicates no significant (>5 sigma) new excess emission (0.1 - 300 GeV) within the IC190124A 90% confidence localization. Assuming a power-law spectrum (photon index = 2.0 fixed) for a point source at the IceCube best-fit position, the >100 MeV flux upper limits (95% confidence) are < 3e-10 ph cm^-2 s^-1 for ~10.5-years (2008-08-04 / 2019-01-24 UTC) integration time, < 1.5e-9 ph cm^-2 s^-1 for one year (2018-01-24 / 2019-01-24 UTC) integration time, and < 7.6e-9 ph cm^-2 s^-1 for one month (2018-12-25 / 2019-01-24 UTC) integration time before the IceCube IC190124A neutrino detection.
Since Fermi normally operates in an all-sky scanning mode, regular monitoring of this source will continue. For this source the Fermi-LAT contact persons are S. Buson (sara.buson at astro.uni-wuerzburg.de <http://astro.uni-wuerzburg.de/>) and R. Angioni (angioni at mpifr-bonn.mpg.de <http://mpifr-bonn.mpg.de/>). 
The Fermi LAT is a pair conversion telescope designed to cover the energy band from 20 MeV to greater than 300 GeV. It is the product of an international collaboration between NASA and DOE in the U.S. and many scientific institutions across France, Italy, Japan and Sweden.