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Related papers: X-Ray view of Misaligned AGNs

200 papers

In recent surveys of Radio-loud AGN, a new sub-class of objects, known as Weak-Line Radio Galaxies (WLRGs) has emerged. These radio galaxies have only weak, low-ionization optical emission lines. In the X-ray band, these objects are much…

Astrophysics · Physics 2007-05-23 Karen T. Lewis , Michael Eracleous , Rita M. Sambruna

The Chandra X-ray observatory has proven to be a vital tool for studying high-energy emission processes in jets associated with Active Galactic Nuclei (AGN).We have compiled a sample of 27 AGN selected from the radio flux-limited MOJAVE…

High Energy Astrophysical Phenomena · Physics 2015-05-27 Brandon Hogan , Matthew Lister , Preeti Kharb , Herman Marshall , Nathan Cooper

Since 2008 the Fermi/LAT instrument has delivered highly time-resolved gamma-ray spectra and detailed variability curves for a steadily increasing number of AGN. For detailed AGN studies the Fermi/LAT data have to be combined with, and…

High Energy Astrophysical Phenomena · Physics 2010-07-05 Lars Fuhrmann

Submillimetre-selected galaxies (SMGs) at high redshift ($z$ $\sim$ 2) are potential host galaxies of active galactic nuclei (AGN). If the local Universe is a good guide, $\sim$ 50$\%$ of the obscured AGN amongst the SMG population could be…

Using a sample of 2922 z<0.2, spectroscopically-identified Active Galactic Nuclei (AGN) we explore the relationship between radio size and the prevalence of extreme ionised outflows, as traced using broad [O III] emission-line profiles in…

Astrophysics of Galaxies · Physics 2019-11-06 S. J. Molyneux , C. M. Harrison , M. E. Jarvis

With the advancement of technology, machine learning-based analytical methods have pervaded nearly every discipline in modern studies. Particularly, a number of methods have been employed to estimate the redshift of gamma-ray loud active…

High Energy Astrophysical Phenomena · Physics 2023-12-13 Sarvesh Gharat , Abhimanyu Borthakur , Gopal Bhatta

Variability is one of the classic features of active galactic nuclei (AGNs). The normalized structure function was applied to distinguish variability samples from OVRO, ASAS-SN and Fermi. A power-law function model was selected to fit the…

High Energy Astrophysical Phenomena · Physics 2026-03-23 Xuan Wei , Jie Tang , Yu Tao

We have developed an efficient Active Galactic Nucleus (AGN) selection method using 18-band Spectral Energy Distribution (SED) fitting in mid-infrared (mid-IR). AGNs are often obscured by gas and dust, and those obscured AGNs tend to be…

Astrophysics of Galaxies · Physics 2017-08-29 Ting-Chi Huang , Tomotsugu Goto , Tetsuya Hashimoto , Nagisa Oi , Hideo Matsuhara

We present a multi-wavelength study of IC 1531 (z=0.02564), an extragalactic radio source associated with the $\gamma$-ray object 3FGL J0009.9-3206 and classified as a blazar of uncertain type in the Third Fermi Large Area Telescope AGN…

High Energy Astrophysical Phenomena · Physics 2018-10-17 T. Bassi , G. Migliori , P. Grandi , C. Vignali , M. A. Pérez-Torres , R. D. Baldi , E. Torresi , A. Siemiginowska , C. Stanghellini

Infrared-faint radio sources (IFRS) form a new class of galaxies characterised by radio flux densities between tenths and tens of mJy and faint or absent infrared counterparts. It has been suggested that these objects are radio-loud active…

We have used FMOS on Subaru to obtain near-infrared spectroscopy of 123 far-infrared selected galaxies in COSMOS and obtain the key rest-frame optical emission lines. This is the largest sample of infrared galaxies with near-infrared…

The recent release of the First Fermi-LAT Source Catalog solidified the predominant association of extragalactic gamma-ray emitters to active galaxies, in particular blazars. A tight connection between AGN jet kinematics and gamma-ray…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-25 Marios Karouzos , Silke Britzen , Arno Witzel , Anton Zensus , Andreas Eckart

While supernova remnants (SNRs) are widely thought to be powerful cosmic-ray accelerators, indirect evidence comes from a small number of well-studied cases. Here we systematically determine the gamma-ray emission detected by the Fermi…

High Energy Astrophysical Phenomena · Physics 2015-07-14 F. de Palma , T. J. Brandt , J. W. Hewitt , G. Johannesson , L. Tibaldo

The Combined NVSS-FIRST Galaxy (CoNFIG) survey was defined by selecting all sources with S_1.4GHz > 1.3Jy from the NRAO VLA Sky Survey (NVSS) in the north field of the Faint Images of the Radio Sky at Twenty-cm (FIRST) survey. We carried…

Astrophysics · Physics 2009-04-14 Melanie A. Gendre , Jasper V. Wall

We study the space density evolution of active galactic nuclei (AGN) using the $610 \ \mathrm{MHz}$ radio survey of the XXL-North field, performed with the Giant Metrewave Radio Telescope (GMRT). The survey covers an area of $30.4 \…

Low-luminosity active galactic nuclei (LLAGNs) are generally believed to be powered by an inner radiatively inefficient, advection-dominated accretion flow (ADAF), an outer truncated thin disk, and a jet. Maoz (2007) recently challenged…

High Energy Astrophysical Phenomena · Physics 2015-05-20 Zhaolong Yu , Feng Yuan , Luis Ho

We investigate the nature of low-luminosity radio-loud active galactic nuclei (RLAGN) selected from the LOFAR Two-metre Sky Survey (LoTSS) first data release (DR1). Using optical, mid-infrared, and radio data, we have conservatively…

Astrophysics of Galaxies · Physics 2024-03-01 J. Chilufya , M. J. Hardcastle , J. C. S. Pierce , J. H. Croston , B. Mingo , X. Zheng , R. D. Baldi , H. J. A. Röttgering

We present a multiwavelength radio study of a sample of nearby Fanaroff-Riley class II (FRII) radio galaxies, matched with the sample of known X-shaped radio sources in size, morphological properties and redshift, using new Giant Metrewave…

Astrophysics · Physics 2015-05-13 Dharam Vir Lal , Martin J. Hardcastle , Ralph P. Kraft

During a search for gamma-ray emission from NGC 3628 (Arp 317), two new unidentified gamma-ray sources, Fermi J1049.7+0435 and J1103.2+1145 have been discovered \cite{ATel}. The detections are made in data from the Large Area Telescope…

High Energy Astrophysical Phenomena · Physics 2015-02-10 Masaki Nishimichi , Takeshi Okuda , Masaki Mori , Philip G. Edwards , Jamie Stevens

We obtained optical imaging polarimetry with the ACS/HRC aboard the HST of the 9 closest radio-galaxies in the 3C catalogue with an FR I morphology. The nuclear sources seen in direct HST images in these galaxies are found to be highly…

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