Fermi-LAT detection of a new gamma-ray source associated with PMN J0158-5004 in the vicinity of the flaring blazar PKS 0208-512
ATel #13847; R. Angioni (SSDC/INFN), S. Ciprini (SSDC/INFN) and A. Yusafzai (ECAP/FAU), on behalf of the Fermi Large Area Telescope Collaboration
on 1 Jul 2020; 21:52 UT
Credential Certification: Roberto Angioni (r.angioni90@gmail.com)
Subjects: >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 candidate blazar PMN J0158-5004, also known as CRATES J0158-5004 , with coordinates R.A. = 29.57088 deg, Dec. = -50.07247 deg (J2000; Healey et al. 2007, ApJS, 171, 61), 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 28 June 2020, with a daily averaged gamma-ray flux (E>100MeV) of (2.1+/-1.1) X 10^-7 photons cm^-2 s^-1 and a single power-law photon index of 1.8+/-0.3 (statistical uncertainties only). The source was detected for the first time in May 2020 and is here confirmed as a new gamma-ray source. The source lies ~2 degrees away, and is distinct from, the flaring gamma-ray blazar PKS 0208-512, which is detected with daily averaged gamma-ray flux (E>100MeV) of (1.0+/-0.2) X 10^-6 photons cm^-2 s^-1 and a single power-law photon index of 2.7+/-0.2 on 28 June 2020.
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. 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.
