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This review gives a brief introduction to the physics and the structure of active galactic nuclei (AGN). The main topics that are being discussed are general accretion, the structure and the spectrum of various types of accretion disks, photoionization and recombination, energy balance and gas temperature, the spectrum of ionized gas including the effect of dust, and the dynamics of ionized...
Over the last few years, high-quality X-ray imaging and spectroscopic data from Chandra and XMM-Newton have added greatly to the understanding of the physics of radio jets. Here we describe the current state of knowledge with an emphasis on the underlying physics used to interpret multiwavelength data in terms of physical parameters.
We review the basic observed and inferred properties of the broad emission-line region in AGNs, as well as the basics of the reverberation-mapping technique that can be used to determine the size and structure of the region. We argue that the current best evidence points to a multi-component line-emitting region, with a disk-like structure, possibly an extension of the accretion disk itself,...
Active galactic nuclei (AGNs) are identi.ed mainly by the properties of visibly hot gas located within the nucleus (e.g., line emitting regions, UV – X-ray emission from the accretion disk) or without (e.g., radio lobes of relativistic plasma). Colder gas and dust however play an important role in the standard model for AGNs. Firstly, there are arguments that the (relatively) cold ISM from...
Galaxies and their nuclear SuperMassive Black Holes (SMBH) appear to be intimately related components of the same fundamental formation and evolutionary process [3], [7]. When the host galaxy contrives to feed its nuclear monster, it unleashes a torrential energy output that can far outshine the gentler and, apart from the occasional supernova, more constant shining of the stellar populations...
The quest for a coherent picture of nuclear activity has witnessed giant leaps in the last decades. Four decades ago, the idea was put forward that accretion of matter onto a massive compact object or a supermassive black hole (SMBH) of mass >106 M⊙ could power very luminous active galactic nuclei (AGN), in particular, quasi-stellar objects (QSOs) (Lynden-Bell 1969; Soltan 1982; Rees 1984)...
This “pedagogical” review describes the key Chandra and XMMNewton extragalactic surveys to date and details some of their implications for active galaxy physics and evolution. We additionally highlight two topics of current widespread interest: (1) X-ray constraints on the active galactic nucleus content of luminous submillimeter galaxies, and (2) the demography and physics of high-redshift...
In this chapter I review the growing evidence that Active Galactic Nuclei (AGN) may play a critical role in the process of galaxy formation. I begin by summarising the observational evidence for a tight link between the formation of supermassive black holes and their hosts. I then review our current understanding for how galaxies form within the paradigm of hierarchical structure formation...
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