By Emmi Meyer-Hofmeister, Henk Spruit
The main luminous compact gadgets are powered via accretion of mass. Accretion disks are the single universal and primary part of those resources on largely assorted scales, starting from shut stellar binaries, galactic black holes and X-ray pulsars to lively galactic nuclei (AGN). Key new advancements in thought and observations, reviewed via specialists within the box, are provided during this ebook. The contributions to the workshop conceal the puzzles provided via the X-UV spectra of AGN and their variability, the new numerical simulations of magnetic fields in disks, the notable habit of the superluminal resource 1915+105 and the "bursting pulsar" 1744-28, to say the various themes.
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Extra resources for Accretion Disks - New Aspects
Short-term continuum variability is a staple of AGNs (and indeed is undisputed evidence of the compactness of the central engine); if the delayed response of the line emitting region to changes in the continuum source is regulated by light-travel time from the latter to the former, then the time lag between variations in the ionizing continuum and in the flux of each velocity component of the line emission directly probes the spatial structure and emissivity properties of the BLR. The technique is widely known as “reverberation” or “echo” mapping (Blandford & McKee 1982; Peterson 1993; Peterson 2002).
Gebhardt et al. 2003). A recent study by Valluri et al. (2004) claims that potentially severe systematics in M• are introduced, unless the number of orbits used in the modeling is at least an order of magnitude larger than the number of observational constraints. More disturbing still is the claim that even in the case of the © 2006 by Taylor & Francis Group, LLC Observational Evidence for Supermassive Black Holes 17 best observational datasets, three-integral models admit too many degrees of freedom to constrain M• , which remains undetermined to within a factor of several.
Although a factor © 2006 by Taylor & Francis Group, LLC 26 Joint Evolution of Black Holes and Galaxies 10 to 100 times larger than the inner accretion disk, and three orders of magnitude larger than the Schwarzschild radius of the SMBH that powers the AGN activity, the BLR is, and will remain, spatially unresolved even using space-based instrumentation. In the early 1980s it was realized that, while preventing direct imaging, the closeness of the BLR to the ionizing continuum source might open a new, unconventional way to map its properties.
Accretion Disks - New Aspects by Emmi Meyer-Hofmeister, Henk Spruit