TITLE: GCN CIRCULAR NUMBER: 27966 SUBJECT: Fermi-LAT Gamma-ray Observations of IceCube-200614A and detection of a new gamma-ray source, Fermi J0202.8+3132 DATE: 20/06/16 14:52:21 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 IC200614A neutrino event (GCN 27941) 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 2020-06-14 at 12:41:21.41 UT (T0) with J2000 position RA =33.84 (+4.77 -6.39) deg, Decl. =31.61(+2.75 -2.28) deg 90% PSF containment. Five cataloged >100 MeV gamma-ray sources (The Fermi-LAT Collaboration 2019, arXiv:1902.10045) are located within the 90% IC200614A localization error. These are  4FGL J0159.0+3313, 4FGL J0202.4+2943, 4FGL J0203.7+3042, 4FGL J0205.2+3212 and 4FGL J0220.2+3246. Based on a preliminary analysis of the LAT data over the timescales of 1-day and 1-month prior to T0, these objects are not significantly detected (> 5 sigma). We searched for  intermediate (days to years) timescale emission from a new gamma-ray transient source. Preliminary analysis indicates no significant (> 5 sigma) new excess emission (> 100 MeV), at the IC200614A best-fit position. 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 < 8e-10 ph cm^-2 s^-1 for ~11-years (2008-08-04 / 2020-06-14 UTC), < 9e-9 (< 8e-8) ph cm^-2 s^-1 for a 1-month (1-day) integration time before T0. Within the 90% confidence localization of the neutrino, ~2.7 deg offset from the best-fit IC200614A position, a >5 sigma excess of gamma rays, Fermi J0202.8+3132 was detected in an analysis of the integrated LAT data (> 100 MeV) between 2008-08-04 and  2020-06-14. Assuming a power-law spectrum, the best-fit localization is (J2000) RA:  30.71, Dec: 31.55 (0.16 deg 99% containment, 0.08 deg 68% containment), with best-fit spectral parameters flux = (5 +/- 3)e-10 ph cm^-2 s^-1 and index = 1.8 +/- 0.2. In a preliminary analysis of the LAT data over one day and one month prior T0, Fermi J0202.8+3132  is not significantly detected in the LAT data. A possible counterpart for Fermi J0202.8+3132 is the BL Lac candidate object NVSSJ020242+313212 (D'Abrusco et al. 2019, ApJS 242, 1), located 0.03 deg from the best-fit LAT localization. Two additional ~4 sigma excess of gamma rays are detected within the 90% confidence localization of IC200614A in an analysis of the LAT data (> 100 MeV) between 2008-08-04 and  2020-06-14. One is found at the best-fit localisation RA= 32.69, Dec= 30.97 (0.15 deg 99% containment), and has best-fit spectral parameters flux = (4 +/- 3)e-10 ph cm^-2 s^-1 and index = (1.8 +/- 0.2). The second one, at best-fit localisation RA= 35.91, Dec= 32.01 (0.2 deg 99% containment), has best-fit spectral parameters flux = (1.3 +/- 0.7)e-9 ph cm^-2 s^-1 and index = (2.2 +/- 0.2). These excesses are located ~1.2 deg and ~1.8 deg away from the best-fit IC200614A position, respectively. In a preliminary analysis of the LAT data over one day and one month prior to T0, they are not significantly detected in the LAT data. All values include the statistical uncertainty only. Since Fermi normally operates in an all-sky scanning mode, regular monitoring of this source will continue. For these observations the Fermi-LAT contact persons 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.