Fermi-LAT detection of enhanced gamma-ray activity from the FSRQ PKS 0047-579
ATel #15370; G. La Mura (LIP, Portugal), on behalf of the Fermi Large Area Telescope Collaboration
on 8 May 2022; 08:51 UT
Credential Certification: Giovanni La Mura (glamura@lip.pt)
Subjects: Gamma Ray, >GeV, AGN, Blazar, Quasar
The Large Area Telescope (LAT), one of the two instruments on the Fermi Gamma-ray Space Telescope, has observed enhanced gamma-ray activity from a source positionally consistent with the flat-spectrum radio quasar PKS 0047-579, also known as 4FGL J0050.0-5736 (The Fermi-LAT collaboration 2020, ApJS, 247, 33), with coordinates R.A. = 12.49780 deg, Decl. = -57.64093 deg (J2000; Johnston et al. 1995, AJ, 110, 880), and redshift z=1.797 (Gattano et al. 2018, A&A, 618, 80).
Preliminary analysis indicates that this source was in an elevated gamma-ray emission state on May 6, 2022, with a daily averaged gamma-ray flux (E>100MeV) of (0.3+/-0.1) X 10^-6 photons cm^-2 s^-1 (statistical uncertainty only). This corresponds to a flux increase of a factor of nearly 20 relative to the average flux reported in the fourth Fermi-LAT catalog (4FGL). The corresponding photon index is 1.82+/-0.18, and is significantly smaller than the 4FGL value of 2.62+/-0.06.
Because Fermi normally operates in an all-sky scanning mode, regular gamma-ray monitoring of this source will continue. The light curve of this source can be obtained through the Fermi-LAT Light Curve Repository (LCR) at https://fermi.gsfc.nasa.gov/ssc/data/access/lat/LightCurveRepository/source.html?source_name=4FGL_J0050.0-5736. We encourage multifrequency observations of this source. For this source, the Fermi-LAT contact person is G. La Mura (glamura@lip.pt).
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.
