Fermi-LAT detection of a new gamma-ray source Fermi J1244.4+1640
ATel #17076; F. Casaburo (INAF-OAR, Sapienza University of Rome, INFN Roma Tor Vergata), S. Ciprini (INFN Roma Tor Vergata, ASI-SSDC), G. La Mura (INAF-OAC), on behalf of the Fermi Large Area Telescope Collaboration
on 11 Mar 2025; 13:39 UT
Credential Certification: Giovanni La Mura (giovanni.lamura@inaf.it)
Subjects: Gamma Ray, AGN, Quasar
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 with J2000 coordinates R.A. = 191.13 deg, Dec. = 16.69 deg and 95% error radius 0.43 deg. This source is not in any published LAT catalog and was not detected by AGILE or EGRET. The error circle includes several radio sources, the most likely counterpart appearing to be SDSS J124426.66+164229.2, a quasar with R.A. = 191.11111 deg, Dec. = 16.70813 deg (Gupta et al., 2016, MNRAS, 461, 2346) and z = 0.673 (Albareti et al. 2017, ApJS, 233, 25).
Preliminary analysis indicates that this source, which we indicate as Fermi J1244.4+1640, was significantly detected (>5 sigma) in a high gamma-ray state on March 08, 2025 , with a daily averaged gamma-ray flux (E>100MeV) of (0.6 +/- 0.2) X 10^-6 photons cm^-2 s^-1 and a single power-law photon index of 2.3 +/- 0.2 (statistical uncertainties only).
Because Fermi normally operates in an all-sky scanning mode, regular gamma-ray monitoring of this source will continue. We encourage multifrequency observations of this source. For this source, the Fermi-LAT contact people are Fausto Casaburo (fausto[dot]casaburo[at]roma2[dot]infn[dot]it), Stefano Ciprini (stefano[dot]ciprini[at]roma2[dot]infn[dot]it) and Giovanni La Mura (giovanni[dot]lamura[at]inaf[dot]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.
