TITLE: GCN CIRCULAR NUMBER: 25932 SUBJECT: Fermi-LAT Gamma-ray Observations of IceCube-191001A DATE: 19/10/03 08:28:18 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 IC191001A neutrino event (GCN 25913)  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 2019-10-01  20:09:18.17 UTC (T0) with J2000 position RA = 314.08 (+6.56, -2.26) deg, Decl. = 12.94 (+1.50, -1.47) deg 90% PSF containment. Two cataloged gamma-ray sources (The Fermi-LAT collaboration, 2019, arXiv:1902.10045) are found within the 90% localization error of IC191001A. These are the millisecond pulsar 4FGL J2052.7+1218 (a.k.a. PSR J2052+1218) and the blazar candidate of uncertain type 4FGL J2115.2+1218 (a.k.a. NVSS J211522+121802), at a distance of 1.1 deg and 4.7 deg from the best fit, respectively. We searched for the existence of intermediate (days to years) timescale emission from a new gamma-ray transient source. Preliminary analysis indicates no significant (>5sigma) new excess emission (> 100 MeV) within the IC191001A 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 < 3.7e-10 ph cm^-2 s^-1 for ~11-years (2008-08-04 / 2019-10-02 UTC), < 2e-8 (< 2.9e-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 persons are S. Garrappa (simone.garrappa atdesy.de ) and S. Buson (sara.buson atgmail.com ). 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.