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Related papers: Large-scale clustering amongst Fermi blazars; evid…

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The $\textit{Fermi}$-LAT Collaboration recently presented a new catalog of gamma-ray sources located within the $40^{\circ} \times 40^{\circ}$ region around the Galactic Center~(Ajello et al. 2017) -- the Second Fermi Inner Galaxy (2FIG)…

High Energy Astrophysical Phenomena · Physics 2017-10-31 Richard Bartels , Dan Hooper , Tim Linden , Siddharth Mishra-Sharma , Nicholas L. Rodd , Benjamin R. Safdi , Tracy R. Slatyer

We study the relation between the mass accretion rate, the jet power, and the black hole mass of blazars. To this aim, we make use of the Sloan Digital Sky Survey (SDSS) and the 11 months catalog of blazars detected at energies larger than…

High Energy Astrophysical Phenomena · Physics 2012-05-18 T. Sbarrato , G. Ghisellini , L. Maraschi , M. Colpi

We present measurements of the angular correlation function of galaxies selected from a B_J=23.5 multicolour survey of two 5 degree by 5 degree fields located at high galactic latitudes. The galaxy catalogue of approximately 400,000…

Astrophysics · Physics 2009-10-31 M. J. I. Brown , R. L. Webster , B. J. Boyle

Context.Coherence in the characteristics of neighboring sources in 2D and 3D space may suggest the existence of large-scale cosmic structures, which are useful for cosmological studies. Numerous works have been conducted to detect such…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-22 N. Mandarakas , D. Blinov , C. Casadio , V. Pelgrims , S. Kiehlmann , V. Pavlidou , K. Tassis

Blazars are active galactic nuclei with relativistic jets pointed almost directly at Earth. Blazars are characterized by strong, apparently stochastic flux variability at virtually all observed wavelengths and timescales, from minutes to…

High Energy Astrophysical Phenomena · Physics 2023-02-16 Aryeh Brill

Building on our previous cross-correlation analysis (Xia et al. 2011) between the isotropic gamma-ray background (IGRB) and different tracers of the large-scale structure of the universe, we update our results using 60-months of data from…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-24 Jun-Qing Xia , Alessandro Cuoco , Enzo Branchini , Matteo Viel

We have investigated a number of factors that can have significant impacts on the classification performance of $\gamma$-ray sources detected by Fermi Large Area Telescope (LAT) with machine learning techniques. We show that a framework of…

Instrumentation and Methods for Astrophysics · Physics 2020-01-29 Shengda Luo , Alex P. Leung , C. Y. Hui , K. L. Li

This paper presents light curves and the first systematic characterization of variability of the 106 objects in the Fermi Large Area Telescope (LAT) Bright AGN Sample (LBAS). Weekly light curves obtained during the first 11 months of survey…

High Energy Astrophysical Phenomena · Physics 2015-05-18 A. A. Abdo

We test the hypothesis that the polarization vectors of flat-spectrum radio sources (FSRS) in the JVAS/CLASS 8.4-GHz surveys are randomly oriented on the sky. The sample with robust polarization measurements is made of $4155$ objects and…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-24 Vincent Pelgrims , Damien Hutsemékers

The Fermi Large Area Telescope (LAT) has detected thousands of sources since its launch in 2008, with many remaining unidentified. Some of these point sources may arise from source confusion. Specifically, there could be extended sources…

High Energy Astrophysical Phenomena · Physics 2025-04-07 Giovanni Cozzolongo , Alison M. W. Mitchell , Samuel T. Spencer , Dmitry Malyshev , Tim Unbehaun

Large-scale structure (LSS) and tracer bias connect observable populations to the cosmic matter distribution. While galaxies are standard tracers, transient events such as gravitational-wave sources can also probe LSS despite large…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-25 Yu-Tong Su , Zhengxiang Li

Aims. We present a sample of 4388 AGNs with available radio core-dominance parameters defined as the ratio of the core flux densities to extended ones, namely, R = Score/Sext., which includes 630 Fermi-detected AGNs respect to the catalog…

Astrophysics of Galaxies · Physics 2019-05-14 Zhi-Yuan Pei , Jun-Hui Fan , Denis Bastieri , Jiang-He Yang , Hu-Bing Xiao

Since 2008 August the Fermi Large Area Telescope (LAT) has provided continuous coverage of the gamma-ray sky yielding more than 5000 gamma-ray sources, but 54% of the detected sources remain with no certain or unknown association with a low…

High Energy Astrophysical Phenomena · Physics 2020-12-01 Chiaro G. , Kovacevic M. , La Mura G

The Fermi Large Area Telescope (Fermi-LAT) 3FHL catalog is the latest catalog of >10 GeV sources and will remain an important resource for the high-energy community for the foreseeable future. Therefore, it is crucial that this catalog is…

High Energy Astrophysical Phenomena · Physics 2020-10-14 Ross Silver , Stefano Marchesi , Lea Marcotulli , Aman Kaur , Meenakshi Rajagopal , Marco Ajello

The clustering of active galactic nuclei (AGN) sheds light on their typical large (Mpc-scale) environments, which can constrain the growth and evolution of supermassive black holes. Here we measure the clustering of luminous X-ray-selected…

Astrophysics of Galaxies · Physics 2020-03-11 M. C. Powell , C. M. Urry , N. Cappelluti , J. T. Johnson , S. M. LaMassa , T. T. Ananna , K. E. Kollmann

We report the results from our analysis of a large set of archival data acquired with the X-ray telescope (XRT) onboard Swift, covering the sky region surrounding objects from the first Fermi Large Area Telescope (LAT) catalogue of…

High Energy Astrophysical Phenomena · Physics 2015-09-16 R. Landi , L. Bassani , J. B. Stephen , N. Masetti , A. Malizia , P. Ubertini

Blazars, a beamed population of active galactic nuclei, radiate high-energy gamma-rays, and thus are a good target for the Gamma Ray Large Area Space Telescope (GLAST). As the blazars trace the large-scale structure of the universe, one may…

Astrophysics · Physics 2008-12-18 Shin'ichiro Ando , Eiichiro Komatsu , Takuro Narumoto , Tomonori Totani

We examine whether a cosmologically significant distribution of dark galaxy group or cluster-sized objects can have an optical depth for multiple imaging of distant background sources which is comparable to that from known galaxies while at…

Astrophysics · Physics 2011-02-11 Yu-Chung N. Cheng , Lawrence M. Krauss

Narrow line Seyfert 1 galaxies (NLSy1s) constitute the AGN subclass associated with systematically smaller black hole masses. A few radio loud ones have been detected in MeV -- GeV energy bands by Fermi and evidence for the presence of…

Astrophysics of Galaxies · Physics 2018-10-23 E. Angelakis , S. Kiehlmann , I. Myserlis , D. Blinov , J. Eggen , R. Itoh , N. Marchili , J. A. Zensus

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