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Related papers: Classifying Unidentified Gamma-ray Sources

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We have discovered six radio millisecond pulsars (MSPs) in a search with the Arecibo telescope of 34 unidentified gamma-ray sources from the Fermi Large Area Telescope (LAT) 4-year point source catalog. Among the 34 sources, we also…

High Energy Astrophysical Phenomena · Physics 2016-03-16 H. T. Cromartie , F. Camilo , M. Kerr , J. S. Deneva , S. M. Ransom , P. S. Ray , E. C. Ferrara , P. F. Michelson , K. S. Wood

The Second Fermi LAT source catalog (Nolan et al. 2012) includes as many as 1,873 sources, but initial attempts to identify counterparts at other wavelengths resulted in 575 sources remaining unidentified. The 2FGL catalog is based on the…

High Energy Astrophysical Phenomena · Physics 2015-06-18 Masaki Nishimichi , Takeshi Okuda , Masaki Mori , Philip G. Edwards , Jamie Stevens

In an attempt to constrain and understand the emission mechanism of gamma rays, we perform a cross-correlation analysis of 15 blazars using light curves in millimetre, optical and gamma rays. We use discrete correlation function and…

High Energy Astrophysical Phenomena · Physics 2015-12-15 V. Ramakrishnan , T. Hovatta , M. Tornikoski , K. Nilsson , E. Lindfors , M. Baloković , A. Lähteenmäki , R. Reinthal , L. Takalo

A significant fraction (~30%) of the high-energy gamma-ray sources listed in the second Fermi LAT catalog (2FGL) are still of unknown origin, being not yet associated with counterparts at low energies. We recently developed a new…

High Energy Astrophysical Phenomena · Physics 2015-06-15 F. Massaro , R. D'Abrusco , A. Paggi , N. Masetti , M. Giroletti , G. Tosti , Howard A. Smith , S. Funk

A direct search of $\gamma$-ray emission centered on multi-frequency selected candidates is a valuable complementary approach to the standard search adopted in current $\gamma$-ray Fermi-LAT catalogs. Our candidates are part of the 2WHSP…

High Energy Astrophysical Phenomena · Physics 2017-02-15 Bruno Arsioli , Yu-Ling Chang

In the fourth \emph{Fermi} Large Area Telescope source catalog (4FGL), 5064 $\gamma$-ray sources are reported, including 3207 active galactic nuclei (AGNs), 239 pulsars, 1336 unassociated sources, 92 sources with weak association with…

High Energy Astrophysical Phenomena · Physics 2021-02-10 Kerui Zhu , Shi-Ju Kang , Yong-Gang Zheng

Context. Based on their overwhelming dominance among associated Fermi gamma ray catalogue sources, it is expected that a large fraction of the unidentified Fermi objects are blazars. Through crossmatching between the positions of…

We study the $\gamma$-ray and broadband spectral energy distribution (SED) properties of a complete sample of 104 bright, radio-selected low-synchrotron peaked (LSP) blazars. Most of the sources have already been detected in the…

High Energy Astrophysical Phenomena · Physics 2018-08-08 B. Arsioli , G. Polenta

Although not designed primarily as a polarimeter, the \textit{Fermi}-Large Area Telescope (LAT) has the potential to detect high degrees of linear polarization from some of the brightest gamma-ray sources. To achieve the needed accuracy in…

Instrumentation and Methods for Astrophysics · Physics 2019-08-14 Matteo Giomi , Rolf Bühler , Carmelo Sgrò , Francesco Longo , William Atwood

According to radiative models, radio galaxies are predicted to produce gamma-rays from the earliest stages of their evolution onwards. The study of the high-energy emission from young radio sources is crucial for providing information on…

High Energy Astrophysical Phenomena · Physics 2022-01-05 Giacomo Principe , Leonardo Di Venere , Giulia Migliori , Monica Orienti , Filippo D'Ammando

Nearly 1/3 of the sources listed in the Third Fermi Large Area Telescope (LAT) catalog (3FGL) remain unassociated. It is possible that predicted and even unanticipated gamma-ray source classes are present in these data waiting to be…

High Energy Astrophysical Phenomena · Physics 2016-07-06 N. Mirabal , E. Charles , E. C. Ferrara , P. L. Gonthier , A. K. Harding , M. A. Sánchez-Conde , D. J. Thompson

Nearly 50% of all sources detected by the Fermi Large Area Telescope are classified as blazars or blazar candidates, one of the most elusive classes of active galaxies. Additional blazars can also be hidden within the sample of unidentified…

High Energy Astrophysical Phenomena · Physics 2020-07-13 E. J. Marchesini , A. Paggi , F. Massaro , N. Masetti , R. D'Abrusco , I. Andruchow

Due to the low gamma-ray fluxes from pulsars above 50 GeV and the small collecting area of space-based telescopes, the gamma-ray emission discovered by the Fermi-LAT in $\sim$150 pulsars is largely unexplored at these energies. In this…

High Energy Astrophysical Phenomena · Physics 2015-05-20 A. McCann

Observations by Fermi LAT enabled us to explore the population of non-recycled gamma-ray pulsars with the set of 89 objects. It was recently noted that there are apparent differences in properties of radio-quiet and radio-loud subsets. In…

High Energy Astrophysical Phenomena · Physics 2017-01-17 E. V. Sokolova , G. I. Rubtsov

We describe a comprehensive pulsar monitoring campaign for the Large Area Telescope (LAT) on the {\em Fermi Gamma-ray Space Telescope} (formerly GLAST). The detection and study of pulsars in gamma rays give insights into the populations of…

A list of 205 gamma-ray strong objects was reported recently as a result of a 3-month integration with the Large Area Telescope on board the Fermi Gamma-Ray Space Telescope. We attempted identification of these objects, cross-correlating…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Y. Y. Kovalev

The $Fermi$-LAT has revealed that rotation powered millisecond pulsars (MSPs) are a major contributor to the Galactic $\gamma$-ray source population. We discuss the $\gamma$-ray emission process within the context of the outer gap…

High Energy Astrophysical Phenomena · Physics 2011-10-26 J. Takata , Y. Wang , K. S. Cheng

The high-frequency radio sky, like the gamma-ray sky surveyed by the Fermi satellite, is dominated by flat spectrum radio quasars and BL Lac objects at bright flux levels. To investigate the relationship between radio and gamma-ray emission…

High Energy Astrophysical Phenomena · Physics 2015-05-18 Elizabeth K. Mahony , Elaine M. Sadler , Tara Murphy , Ronald D. Ekers , Philip G. Edwards , Marcella Massardi

Fermi has detected over 200 pulsars above 100 MeV. In a previous work, using 3 years of LAT data (1FHL catalog) we reported that 28 of these pulsars show emission above 10 GeV; only three of these, however, were millisecond pulsars (MSPs).…

High Energy Astrophysical Phenomena · Physics 2017-12-20 Pablo M. Saz Parkinson , Andrea Belfiore , David Carreto Fidalgo , Colin J. Clark , Matthew Kerr , Lars Nieder

The population of $\gamma$-ray emitting millisecond pulsars (MSPs) is studied by using Monte-Carlo techniques. We simulate the Galactic distributions of the MSPs, and apply the outer gap model for the $\gamma$-ray emission from each…

High Energy Astrophysical Phenomena · Physics 2017-02-22 J. Takata , Y. Wang , K. S. Cheng