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Title: Radio Follow-up on All Unassociated Gamma-Ray Sources from the Third Fermi Large Area Telescope Source Catalog

Abstract

The third Fermi Large Area Telescope γ -ray source catalog (3FGL) contains over 1000 objects for which there is no known counterpart at other wavelengths. The physical origin of the γ -ray emission from those objects is unknown. Such objects are commonly referred to as unassociated and mostly do not exhibit significant γ -ray flux variability. We performed a survey of all unassociated γ -ray sources found in 3FGL using the Australia Telescope Compact Array and Very Large Array in the range 4.0–10.0 GHz. We found 2097 radio candidates for association with γ -ray sources. The follow-up with very long baseline interferometry for a subset of those candidates yielded 142 new associations with active galactic nuclei that are γ -ray sources, provided alternative associations for seven objects, and improved positions for another 144 known associations to the milliarcsecond level of accuracy. In addition, for 245 unassociated γ -ray sources we did not find a single compact radio source above 2 mJy within 3 σ of their γ -ray localization. A significant fraction of these empty fields, 39%, are located away from the Galactic plane. We also found 36 extended radio sources that are candidates for association with a corresponding γmore » -ray object, 19 of which are most likely supernova remnants or H ii regions, whereas 17 could be radio galaxies.« less

Authors:
 [1];  [2];  [3];  [4]
  1. National Radio Astronomy Observatory, P.O. Box O, Socorro, NM 87801 (United States)
  2. Astrogeo Center, Falls Church, VA 22043 (United States)
  3. Department of Physics and Astronomy, University of New Mexico, Albuquerque, NM 87131 (United States)
  4. CSIRO Astronomy and Space Science, P.O. Box 76, Epping, 1710 NSW (Australia)
Publication Date:
OSTI Identifier:
22661191
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 838; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCURACY; CATALOGS; COSMIC GAMMA SOURCES; EMISSION; GALAXY NUCLEI; GAMMA RADIATION; INTERFEROMETRY; RADIO GALAXIES; SUPERNOVA REMNANTS; TELESCOPES

Citation Formats

Schinzel, Frank K., Petrov, Leonid, Taylor, Gregory B., and Edwards, Philip G., E-mail: fschinze@nrao.edu. Radio Follow-up on All Unassociated Gamma-Ray Sources from the Third Fermi Large Area Telescope Source Catalog. United States: N. p., 2017. Web. doi:10.3847/1538-4357/AA6439.
Schinzel, Frank K., Petrov, Leonid, Taylor, Gregory B., & Edwards, Philip G., E-mail: fschinze@nrao.edu. Radio Follow-up on All Unassociated Gamma-Ray Sources from the Third Fermi Large Area Telescope Source Catalog. United States. doi:10.3847/1538-4357/AA6439.
Schinzel, Frank K., Petrov, Leonid, Taylor, Gregory B., and Edwards, Philip G., E-mail: fschinze@nrao.edu. Sat . "Radio Follow-up on All Unassociated Gamma-Ray Sources from the Third Fermi Large Area Telescope Source Catalog". United States. doi:10.3847/1538-4357/AA6439.
@article{osti_22661191,
title = {Radio Follow-up on All Unassociated Gamma-Ray Sources from the Third Fermi Large Area Telescope Source Catalog},
author = {Schinzel, Frank K. and Petrov, Leonid and Taylor, Gregory B. and Edwards, Philip G., E-mail: fschinze@nrao.edu},
abstractNote = {The third Fermi Large Area Telescope γ -ray source catalog (3FGL) contains over 1000 objects for which there is no known counterpart at other wavelengths. The physical origin of the γ -ray emission from those objects is unknown. Such objects are commonly referred to as unassociated and mostly do not exhibit significant γ -ray flux variability. We performed a survey of all unassociated γ -ray sources found in 3FGL using the Australia Telescope Compact Array and Very Large Array in the range 4.0–10.0 GHz. We found 2097 radio candidates for association with γ -ray sources. The follow-up with very long baseline interferometry for a subset of those candidates yielded 142 new associations with active galactic nuclei that are γ -ray sources, provided alternative associations for seven objects, and improved positions for another 144 known associations to the milliarcsecond level of accuracy. In addition, for 245 unassociated γ -ray sources we did not find a single compact radio source above 2 mJy within 3 σ of their γ -ray localization. A significant fraction of these empty fields, 39%, are located away from the Galactic plane. We also found 36 extended radio sources that are candidates for association with a corresponding γ -ray object, 19 of which are most likely supernova remnants or H ii regions, whereas 17 could be radio galaxies.},
doi = {10.3847/1538-4357/AA6439},
journal = {Astrophysical Journal},
number = 2,
volume = 838,
place = {United States},
year = {Sat Apr 01 00:00:00 EDT 2017},
month = {Sat Apr 01 00:00:00 EDT 2017}
}