TITLE: GCN CIRCULAR NUMBER: 26261 SUBJECT: Fermi-LAT Gamma-ray Observations of IceCube-191119A DATE: 19/11/19 23:15:21 GMT FROM: Simone Garrappa at DESY S. Garrappa (DESY-Zeuthen) and S. Buson (Univ. of Wuerzburg) on behalf of the Fermi-LAT collaboration: We report an analysis of observations of the vicinity of the high-energy IC191119A neutrino event (GCN 26258) 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 2019-11-19 01:01:29.38 UT (T0) with J2000 position RA = 230.10 (+4.76, -6.48) deg, Decl. = 3.17 (+3.36, -2.09) deg 90% PSF containment. Several cataloged >100 MeV gamma-ray sources are located within the 90% IC191119A localization error. Based on a preliminary analysis of the LAT data, none of those is significantly detected at gamma-rays over a 1-day and 1-month timescale prior T0. We searched for the existence of intermediate (months to years) timescale emission from a new gamma-ray transient source. Preliminary analysis indicates no significant (>5sigma) new excess emission (>100 MeV) within the IC191119A 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 limit (95% confidence) is < 6e-10 ph cm^-2 s^-1 for ~11-years (2008-08-04 / 2019-11-19 UTC), < 1e-8 (< 1e-7) ph cm^-2 s^-1 for a 1-month (1-day) integration time before T0. Since Fermi normally operates in an all-sky scanning mode, regular monitoring of this source will continue. For this source the Fermi-LAT contact person are S. Garrappa (simone.garrappa at desy.de) and S. Buson (sara.buson at uni-wuerzburg.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.