Download or read book Reverberation Mapping of the Broad line Region in Active Galactic Nuclei written by Rutherford Appleton Laboratory. Workshop on Astronomy and Astrophysics and published by . This book was released on 1994 with total page 410 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Reverberation Mapping of the Broad line Region in Active Galactic Nuclei written by P. M. Gondhalekar and published by . This book was released on 1994 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Physics of Active Galactic Nuclei at all Scales written by Danielle Alloin and published by Springer. This book was released on 2006-09-07 with total page 243 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains a collection of lecture notes written by recognized experts in the field of Active Galactic Nuclei (AGN). The collection is aimed at providing both an introduction and at the same time an overview of the state-of-the-art of AGN research. This book also addresses the still not entirely understood link of an AGN with its host galaxy and also the related question of the birth and growth of massive black holes in the Universe.
Download or read book An Introduction to Active Galactic Nuclei written by Bradley M. Peterson and published by Cambridge University Press. This book was released on 1997-02-13 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt: How can we test if a supermassive black hole lies at the heart of every active galactic nucleus? What are LINERS, BL Lacs, N galaxies, broad-line radio galaxies and radio-quiet quasars and how do they compare? This timely textbook answers these questions in a clear, comprehensive and self-contained introduction to active galactic nuclei - for graduate students in astronomy and physics. The study of AGN is one of the most dynamic areas of contemporary astronomy, involving one fifth of all research astronomers. This textbook provides a systematic review of the observed properties of AGN across the entire electromagnetic spectrum, examines the underlying physics, and shows how the brightest AGN, quasars, can be used to probe the farthest reaches of the Universe. This book serves as both an entry point to the research literature and as a valuable reference for researchers in the field.
Download or read book Structure and Kinematics of Quasar Broad Line Regions written by C. Martin Gaskell and published by . This book was released on 1999 with total page 480 pages. Available in PDF, EPUB and Kindle. Book excerpt: Annotation Proceedings of a March 1998 meeting, with papers in sections on general considerations and photoionization modeling, profile variation and reverberation mapping, flows, disks, narrow-line Seyfert 1 galaxies, the intermediate line region and lower-velocity gas, X-ray warm absorber and dust, and unified theories and connections with extended emission. Specific topics include spectral variability of NGC 4151 during 1990 and disk emission line issues. Lacks a subject index. The editor is associated with the University of Nebraska. Annotation c. Book News, Inc., Portland, OR (booknews.com)
Download or read book A New Method for Measuring Black Hole Masses in Active Galaxies written by Anna K. Pancoast and published by . This book was released on 2015 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt: Measuring the masses of supermassive black holes in active galactic nuclei (AGN) allows us to trace their evolution over cosmic time and understand how black holes coevolve with their host galaxies. We present a new technique to measure black hole masses and constrain the structure of the broad line region in AGN using reverberation mapping data. We begin by developing a simply parameterized phenomenological model of the broad line region geometry and dynamics and apply this model to high-quality reverberation mapping data for six AGN from the Lick AGN Monitoring Project 2008 and 2011 datasets. The results of this analysis provide the most precise AGN black hole masses from reverberation mapping to date and the first detailed constraints on the geometry and dynamics of the broad line region emission. Specifically, we find that the shape of the broad line region is generally a close to face-on thick disk with preferential emission from the far side, and that the dynamics range from inflow to near-circular orbits. In addition, we present photometric AGN light curves using image subtraction for the Lick AGN Monitoring Project 2011 dataset as a first step towards modeling the broad line region in a larger sample of AGN.
Download or read book The Physics and Evolution of Active Galactic Nuclei written by Hagai Netzer and published by Cambridge University Press. This book was released on 2013-09-16 with total page 369 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive introduction to the theory underpinning our study of active galactic nuclei and the ways we observe them.
Download or read book Dust Reverberation Mapping of Active Galactic Nuclei written by Shaelyn Shadwell and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: "In the next few years, large-scale surveys with a time domain element, such as the ten-year Legacy Survey of Space and Time (LSST), will produce an immense data set to study variable and transient astronomical sources such as active galactic nuclei (AGN). AGN are located at the center of most galaxies and have five major components: a supermassive black hole (SMBH), an accretion disk, the broad-line region (BLR), a dusty circumnuclear torus, and the narrow-line region (NLR). The torus is believed to have a two-component structure: a geometrically thin circumnuclear disk and a hollow dusty cone along the polar axis. The torus absorbs the ultraviolet (UV)/optical light from the accretion disk and re-emits it in the infrared (IR). In order to study the properties of the torus, techniques such as dust reverberation mapping are needed since AGN, at large distances, cannot be resolved by direct imaging. Reverberation mapping uses the differences in the UV/optical and IR light travel times (lags) to determine the properties of the torus region. This thesis focuses on the use of the TOrus Reverberation MApping Code, TORMAC, to create simulations of the response of the IR dust emission to an input AGN light curve. Both an observed optical light curve, that of MCG-06-30-15, a narrow-line Seyfert 1 (NLS1) AGN, and a simulated AGN light curve were used as inputs. These simulations are used to determine how observing strategies (time baselines and observing cadences) and practical limitations (such as seasonal gaps, irregular sampling) affect how much information can be recovered about the properties of the torus region. In addition, I examined how various torus parameters affect the lags recovered from reverberation mapping. The work performed in this thesis will help inform the design of future optical-IR monitoring campaigns, as well as, to better understand the uncertainties in previous studies - especially those with sparse sampling and limited time duration."--Abstract.
Download or read book The Central Engine of Active Galactic Nuclei written by Luis C. Ho and published by . This book was released on 2007 with total page 830 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Active Galactic Nuclei written by Volker Beckmann and published by John Wiley & Sons. This book was released on 2012-09-24 with total page 390 pages. Available in PDF, EPUB and Kindle. Book excerpt: Active Galactic Nuclei This AGN textbook gives an overview on the current knowledge of the Active Galacitc Nuclei phenomenon. The spectral energy distribution will be discussed, pointing out what can be observed in different wavebands. The different physical models are presented together with formula important for the understanding of AGN physics. Furthermore, the authors discuss the AGN with respect to its environment, host galaxy, feedback in galaxies and in clusters of galaxies, variability, etc. and finally the cosmological evolution of the AGN phenomenon. This book includes phenomena based on new results in the X-Ray and gamma-ray domain from new telescopes such as Chandra, XMM-Newton, the Fermi Gamma-Ray Space Telescope, and the VHE regime not mentioned so far in AGN books. Those and other new developments as well as simulations of AGN merging events and formations, enabled through latest super-computing capabilities. From the contents: The observational picture of AGN Radiative processes The central engine AGN types and unification AGN through the electromagnetic spectrum AGN variability Environment Quasars and cosmology Formation, evolution and the ultimate fate of AGN What we do not know (yet)
Download or read book Advanced Lectures on the Starburst AGN Connection written by D. Kunth and published by World Scientific. This book was released on 2001 with total page 396 pages. Available in PDF, EPUB and Kindle. Book excerpt: A group of leading experts in the field of starbursts and active galactic nuclei have joined hands to produce this review volume which covers the starburst-AGN connection, and the tests to be carried out with the upcoming new astronomical facilities to ascertain the relevance of both components to the formation and evolution of galaxies.The book is addressed to advanced graduate students and researchers in the fields of active galactic nuclei and young galaxies.
Download or read book Robotic Observatories written by M. F. Bode and published by John Wiley & Sons. This book was released on 1995 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Active Galactic Nuclei written by Professor R. D. Blandford and published by Springer. This book was released on 2013-12-14 with total page 289 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Systematic Errors in Black Hole Mass Measurement Using Reverberation Mapping written by Megan Comins and published by . This book was released on 2008 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Active galactic nuclei (AGNs) are extremely energetic central regions of galaxies whose brightness cannot be attributed to stars alone. A typical AGN emits at least the same amount of energy that is emitted by an entire galaxy of stars, but in a much smaller volume. The basic paradigmatic model of an AGN is a dense gaseous disk through which matter is actively accreting onto a central supermassive black hole. This is surrounded by a region of relatively dense broad-line emitting clouds and then, further out, a region of relatively low-density narrow-line emitting clouds, known as the broad-line region (BLR) and narrow-line region (NLR), respectively. The disk is adding mass to the black hole and, in the process, releasing radiant energy; this region is often referred to as the "central engine". The BLR is relatively near to the central engine, and it is thus a useful probe of this central region. One technique used to explore the BLR is reverberation mapping, which can reveal the structure and kinematics of the emission-line gas. The goal of this project is to explore how a measurement of the black hole mass, using reverberation mapping, within an AGN changes due to systematic effects inherent in using both a wind-based AGN model, as well as combination disk+wind model. This aim is to address two specific questions. First, how does the black hole mass measurement change when we characterize such a region by only two numbers that characterize the velocity dispersion of the emitting gas and the mean reverberation response time? The BLR is a complex region and we seek to determine how much information one loses through a simplified characterization. Second, how does the geometry of the wind affect the measurement of the black hole mass? Specifically, we explored the effects of changing the opening angle of a conical wind and its inclination with respect to an Earth-based observer. These questions are important to help discern the structure of the BLR. This model will help to gather intuition about how the geometry and kinematics of the BLR affect a black hole mass measurement obtained through reverberation mapping.
Download or read book Consequences of Hot Gas in the Broad Line Region of Active Galactic Nuclei written by Timothy Raymond Kallman and published by . This book was released on 1985 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Quasars at All Cosmic Epochs written by Paola Marziani and published by Frontiers Media SA. This book was released on 2018-10-05 with total page 447 pages. Available in PDF, EPUB and Kindle. Book excerpt: The last 50 years have seen a tremendous progress in the research on quasars. From a time when quasars were unforeseen oddities, we have come to a view that considers quasars as active galactic nuclei, with nuclear activity a coming-of-age experienced by most or all galaxies in their evolution. We have passed from a few tens of known quasars of the early 1970s to the 500,000 listed in the catalogue of the Data Release 14 of the Sloan Digital Sky Survey. Not surprisingly, accretion processes on the central black holes in the nuclei of galaxies — the key concept in our understanding of quasars and active nuclei in general — have gained an outstanding status in present-day astrophysics. Accretion produces a rich spectrum of phenomena in all bands of the electromagnetic spectrum. The power output of highly-accreting quasars has impressive effects on their host galaxies. All the improvement in telescope light gathering and in computing power notwithstanding, we still miss a clear connection between observational properties and theory for quasars, as provided, for example, by the H-R diagram for stars. We do not yet have a complete self-consistent view of nuclear activity with predictive power, as we do for main-sequence stellar sources. At the same time quasars offer many “windows open onto the unknown". On small scales, quasar properties depend on phenomena very close to the black hole event horizon. On large scales, quasars may effect evolution of host galaxies and their circum-galactic environments. Quasars’ potential to map the matter density of the Universe and help reconstruct the Universe’s spacetime geometry is still largely unexploited. The times are ripe for a critical assessment of our present knowledge of quasars as accreting black holes and of their evolution across the cosmic time. The foremost aim of this research topic is to review and contextualize the main observational scenarios following an empirical approach, to present and discuss the accretion scenario, and then to analyze how a closer connection between theory and observation can be achieved, identifying those aspects of our understanding that are still on a shaky terrain and are therefore uncertain knowledge. This research topic covers topics ranging from the nearest environment of the black hole, to the environment of the host galaxies of active nuclei, and to the quasars as markers of the large scale structure and of the geometry of spacetime of the Universe. The spatial domains encompass the accretion disk, the emission and absorption regions, circum-nuclear starbursts, the host galaxy and its interaction with other galaxies. Systematic attention is devoted to some key problems that remain outstanding and are clearly not yet solved: the existence of two quasar classes, radio quiet and radio loud, and in general, the systematic contextualization of quasar properties the properties of the central black hole, the dynamics of the accretion flow in the inner parsecs and the origin of the accretion matter, the quasars’ small and large scale environment, the feedback processes produced by the black hole into the host galaxy, quasar evolutionary patterns from seed black holes to the present-day Universe, and the use of quasars as cosmological standard candles. The timing is appropriate as we are now witnessing a growing body of results from major surveys in the optical, UV X, near and far IR, and radio spectral domains. Radio instrumentation has been upgraded to linear detector — a change that resembles the introduction of CCDs for optical astronomy — making it possible to study radio-quiet quasars at radio frequencies. Herschel and ALMA are especially suited to study the circum-nuclear star formation processes. The new generation of 3D magnetohydrodynamical models offers the prospective of a full physical modeling of the whole quasar emitting regions. At the same time, on the forefront of optical astronomy, applications of adaptive optics to long-slit spectroscopy is yielding unprecedented results on high redshift quasars. Other measurement techniques like 2D and photometric reverberation mapping are also yielding an unprecedented amount of data thanks to dedicated experiments and instruments. Thanks to the instrumental advances, ever growing computing power as well as the coming of age of statistical and analysis techniques, the smallest spatial scales are being probed at unprecedented resolution for wide samples of quasars. On large scales, feedback processes are going out of the realm of single-object studies and are entering into the domain of issues involving efficiency and prevalence over a broad range of cosmic epochs. The Research Topic "Quasars at all Cosmic Epochs" collects a large fraction of the contributions presented at a meeting held in Padova, sponsored jointly by the National Institute for Astrophysics, the Padova Astronomical Observatory, the Department of Physics and Astronomy of the University of Padova, and the Instito de Astrofísica de Andalucía (IAA) of the Consejo Superiór de Investigación Cientifica (CSIC). The meeting has been part of the events meant to celebrate the 250th anniversary of the foundation of the Padova Observatory.
Download or read book Variability of Active Galactic Nuclei written by and published by . This book was released on 1991 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
