Fermi-LAT detection of a new gamma-ray source associated with the flat-spectrum radio source PMN J0313+0228
ATel #13463; R. Angioni (SSDC/INFN) on behalf of the Fermi Large Area Telescope Collaboration
on 9 Feb 2020; 23:29 UT
Credential Certification: Roberto Angioni (r.angioni90@gmail.com)
Subjects: Gamma Ray, >GeV, Request for Observations, AGN
The Large Area Telescope (LAT), one of the two instruments on the Fermi Gamma-ray Space Telescope, has observed gamma-ray emission from a source positionally consistent with the flat-spectrum radio source PMN J0313+0228, also known as TXS 0310+022, with coordinates R.A. = 47.656626 deg, Decl. = 2.290119 deg (J2000; Kovalev et al. 2007 AJ, 133, 1236), and unknown redshift. This source is not in any published LAT catalog and was not detected by AGILE or EGRET.
Preliminary analysis indicates that this source was significantly detected (>5 sigma) in a high gamma-ray state on 8 February 2020, with a daily averaged gamma-ray flux (E>100MeV) of (4.1+/-1.3) X 10^-7 photons cm^-2 s^-1 and a single power-law photon index of 2.4+/-0.3 (statistical uncertainties only).
Because Fermi normally operates in an all-sky scanning mode, regular gamma-ray monitoring of this source will continue. A Target of Opportunity observation with the Neil Gehrels Swift Observatory has already been scheduled. We encourage further multifrequency observations of this source. Optical spectroscopy would be especially useful since the object does not have a measured redshift. For this source, the Fermi-LAT contact person is Roberto Angioni (roberto.angioni@ssdc.asi.it).
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.
