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Related papers: Cosmic evolution and unified models for radio AGN

200 papers

We do not fully understand the dynamics and evolution of a radio galaxy. Models of classical double (Type II) sources are in a reasonable state, but these objects are rare. Non-type II sources (generically called Type I) are far more…

Astrophysics · Physics 2007-05-23 Jean Eilek

In the currently popular orientation-based unified scheme, a radio galaxy appears as a quasar when its principal radio-axis happens to be oriented within a certain cone opening angle around the observer's line of sight. Due to geometrical…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-11 Ashok K. Singal , Raj Laxmi Singh

Previously developed analytic models for the evolution of cosmic string and monopole networks are applied to networks of monopoles attached to two or more strings; the former case is usually known as cosmic necklaces. These networks are a…

High Energy Physics - Phenomenology · Physics 2014-11-21 C. J. A. P. Martins

Since the discovery of active galactic nuclei (AGN) and their subclasses, a unification scheme of AGN has been long sought. Orientation-based unified models predict that some of the diversity within AGN subclasses can be explained by the…

Astrophysics of Galaxies · Physics 2020-01-08 Suk Yee Yong , Rachel L. Webster , Anthea L. King , Nicholas F. Bate , Kathleen Labrie , Matthew J. O'Dowd

It has been speculated that low luminosity radio-loud AGN have the potential to serve as an important source of AGN feedback, and may be responsible for suppressing star-formation activity in massive elliptical galaxies at late times. As…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 K. McAlpine , M. J. Jarvis , D. G. Bonfield

The cosmological two brane model is discussed in detail. An elegant method for deriving the generalised non-linear equations for the interbrane distance is presented. These equations are used to identify equilibrium positions of the radion,…

High Energy Physics - Phenomenology · Physics 2007-05-23 Ian R. Vernon , Anne-Christine Davis

We propose the unified model of compact radio sources, i.e. of pulsars, maser sources, and active galactic nuclei. The unification is based on the wavelength dependence of radio source size. It is shown that the compact sources are…

Astrophysics · Physics 2007-05-23 F. V. Prigara

Several problems regarding the process of galaxy formation are still open. One of them is the role played by AGN phenomena in contributing to galaxy build-up and to Star Formation (SF) quenching. On the other hand, the theory of AGN…

Astrophysics of Galaxies · Physics 2015-04-15 Nicola Malavasi , Sandro Bardelli , Paolo Ciliegi , Olivier Ilbert , Lucia Pozzetti , Elena Zucca

We present a study of the evolution of the fraction of radio-loud active galactic nuclei (AGN) as a function of their host stellar mass. We make use of two samples of radio galaxies: one in the local universe, $0.01 < z < 0.3$, using a…

Astrophysics of Galaxies · Physics 2015-06-24 W. L. Williams , H. J. A. Röttgering

We review the possible mechanisms for the generation of cosmological magnetic fields, discuss their evolution in an expanding Universe filled with the cosmic plasma and provide a critical review of the literature on the subject. We put…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 R. Durrer , A. Neronov

The unification model for powerful radio galaxies and radio-loud quasars postulates that these objects are intrinsically the same but viewed along different angles. Herschel Space Observatory data permit the assessment of that model in the…

Astrophysics of Galaxies · Physics 2015-06-11 P. Podigachoski , P. D. Barthel , M. Haas , C. Leipski , B. Wilkes

Following previous work, we further confirm that the cosmic evolution of steep-spectrum radio-loud AGNs (active galactic nuclei) can be reproduced by a simple combination of density evolution (DE) and luminosity evolution (LE). This mixture…

High Energy Astrophysical Phenomena · Physics 2018-10-31 Zunli Yuan , Jiancheng Wang , Ming Zhou , Longhua Qin , Jirong Mao

For a few years now, cosmology has a standard model. By this term, we mean a consistent theoretical background which is at the same time simple and broad enough to offer coherent explanations for the vast majority of cosmological phenomena.…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-26 Matthias Bartelmann

The discovery of the M-sigma relation, the local galaxy bimodality, and the link between black-hole and host-galaxy properties, have raised the question whether AGN play a role in galaxy evolution. Several theoretical models implement AGN…

Astrophysics of Galaxies · Physics 2014-12-24 M. Vitale , L. Fuhrmann , M. Garcia-Marin , A. Eckart , J. Zuther , A. M. Hopkins

The cosmological evolution of neutral hydrogen is an efficient way of tracing structure formation with redshift. It indicates the rate of evolution of gas into stars and hence the gas consumption and rate star formation history of the…

Astrophysics · Physics 2016-11-03 Celine Peroux , Richard G. McMahon , Mike Irwin , Lisa J. Storrie-Lombardi

Deep and high resolution radio observations of the Hubble Deep Field and flanking fields have shown the presence of two distant edge-darkened FR I radio galaxies, allowing for the first time an estimate of their high redshift space density.…

Astrophysics · Physics 2009-11-07 Ignas Snellen , Philip Best

Some key issues in AGN and galaxy formation are discussed. Very successful Unified Models explain much of the variety of AGN with orientation effects; ingredients are shadowing by a dusty "torus" and relativistic beaming. A spinoff result…

Astrophysics of Galaxies · Physics 2023-08-10 Robert R. J. Antonucci

The current paradigm for radio-quiet AGNs is reviewed, taking into account new results from recent large-scale surveys carried out from the ground and from space. Topics include structure of the central engine, AGN demography,…

Astrophysics · Physics 2007-05-23 Sylvain Veilleux

We present the first joint analysis of catalogs of radio galaxies and quasars to determine if their sky distribution is consistent with the standard $\Lambda$CDM model of cosmology. This model is based on the cosmological principle, which…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-29 Nathan Secrest , Sebastian von Hausegger , Mohamed Rameez , Roya Mohayaee , Subir Sarkar

The spectra of Active Galactic Nuclei (AGNs) are often characterized by a wealth of emission lines with different profiles and intensity ratios that led to a complicated classification. Their electro-magnetic radiation spans more than 10…