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Related papers: Tests of a Structure for Quasars

200 papers

The model I recently proposed for the structure of quasars offers to unify the many aspects of Type 1 AGN: emission lines, absorption lines and reflection features. This makes the model heavily overconstrained by observation and readily…

Astrophysics · Physics 2007-05-23 Martin Elvis

Feedback from quasars and AGNs is being invoked frequently in several cosmological settings. Currently, order of magnitude, or more, uncertainties in the structure of both the wind and the 'obscuring torus' make predictions highly…

Astrophysics · Physics 2007-05-23 Martin Elvis

After 40 years we have no "low" theory of quasars to predict the atomic absorption and emission features so abundant in quasar spectra. Here I take the first step, using results selected for their diagnostic power to build an "observational…

Astrophysics · Physics 2007-05-23 Martin Elvis

We propose a simple unifying structure for the inner regions of quasars and AGN. This empirically derived model links together the BALs, the narrow UV/X-ray ionized absorbers, the BELR, and the Compton scattering/fluorescing regions into a…

Astrophysics · Physics 2009-10-31 Martin Elvis

A quasar wind model is proposed to describe the spatial and velocity structure of the broad line region. This model requires detailed photoionization and magnetohydrodynamic simulation, as the broad line region it too small for direct…

Astrophysics · Physics 2008-09-17 Andrea Ruff

Various unification schemes interpret the complex phenomenology of quasars and luminous active galactic nuclei (AGN) in terms of a simple picture involving a central black hole, an accretion disc and an associated outflow. Here, we continue…

Astrophysics of Galaxies · Physics 2016-02-24 James H. Matthews , Christian Knigge , Knox S. Long , Stuart A. Sim , Nick Higginbottom , Sam W. Mangham

In this review I concentrate exclusively on models for the large-scale structure created by jet flows in AGN. I briefly mention models for the evolution and emission of these objects and how they can also be applied to microquasars. While…

Astrophysics · Physics 2009-04-14 Christian R. Kaiser

Modeling the outflow of planetary atmospheres is important for understanding the evolution of exoplanet systems and for interpreting their observations. Modern theoretical models of exoplanet atmospheres become increasingly detailed and…

Earth and Planetary Astrophysics · Physics 2021-06-30 P. B. Isakova , Ya. N. Pavlyuchenkov , E. S. Kalinicheva , V. I. Shematovich

Thermal mid-infrared emission of quasars requires an obscuring structure that can be modeled as a magneto-hydrodynamic wind in which radiation pressure on dust shapes the outflow. We have taken the dusty wind models presented by Keating and…

Astrophysics of Galaxies · Physics 2015-05-19 S. C. Gallagher , J. E. Everett , M. M. Abado , S. K. Keating

The best motivated alternatives to general relativity are scalar-tensor theories, in which the gravitational interaction is mediated by one or several scalar fields together with the usual graviton. The analysis of their various…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Gilles Esposito-Farese

Until very recently, few constraints existed on the physics of jets, even though they represent the first known evidence of mass outflow in AGN. This has begun to change with HST and Chandra observations, which allow us to observe…

Astrophysics · Physics 2007-05-23 Eric S. Perlman , Herman L. Marshall , John A. Biretta

We will briefly examine the following three issues related to the AGN synthesis models for X-ray background: 1) the possibility that absorbed AGNs evolve faster than unabsorbed ones; 2) the existence of the still debated population of…

Astrophysics · Physics 2007-05-23 R. Gilli

I develop a detailed empirical model for the chromosphere and wind of 31 Cyg based on a previously published analysis of IUE spectra from the 1993 eclipse and on the thermodynamics of how the wind must be driven. I then use this model to…

Astrophysics · Physics 2009-11-13 Joel A. Eaton

We review and clarify the assumptions of our basic model for neutrino production in the cores of quasars, as well as those modifications to the model subsequently made by other workers. We also present a revised estimate of the neutrino…

Astrophysics · Physics 2011-04-15 F. W. Stecker , M. H. Salamon

A key to understanding quasar unification paradigms is the emission properties of broad absorption line quasars (BALQs). The fact that only a small fraction of quasar spectra exhibit deep absorption troughs blueward of the broad permitted…

Astrophysics of Galaxies · Physics 2018-06-20 Suk Yee Yong , Anthea L. King , Rachel L. Webster , Nicholas F. Bate , Matthew J. O'Dowd , Kathleen Labrie

We critically examine recent claims of a high solar metallicity by von Steiger \& Zurbuchen (2016) based on \textit{in situ} measurements of the solar wind, rather than the standard spectroscopically-inferred abundances (Asplund et al.…

Current models of galaxy formation require star formation in high-mass galaxies to be limited by poorly understood mechanisms of quasar feedback. Feedback processes can be studied by examining the molecular gas content of AGN hosts through…

Astrophysics of Galaxies · Physics 2019-10-09 Patrick C. Breysse , Rachael M. Alexandroff

We consider if outflowing winds that are detected via narrow absorption lines (NALs) with FWHM of $<$ 500 km/s (i.e., NAL outflows) in quasar spectra contribute to feedback. As our sample, we choose 11 NAL systems in eight optically…

Astrophysics of Galaxies · Physics 2025-08-01 Toru Misawa , Jane C. Charlton , Michael Eracleous

We present UV/optical spectropolarimetric modelling of the phenomenologically-based structure for quasars proposed by Elvis (2000). In this first paper of a series, we explore the continuum polarisation emerging from radiatively accelerated…

High Energy Astrophysical Phenomena · Physics 2013-10-07 F. Marin , R. W. Goosmann

The range of currently proposed active galactic nucleus (AGN) far-infrared templates results in uncertainties in retrieving host galaxy information from infrared observations and also undermines constraints on the outer part of the AGN…

Astrophysics of Galaxies · Physics 2017-05-26 Jianwei Lyu , George H. Rieke
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