Download or read book Quasar Astronomy written by Daniel W. Weedman and published by Cambridge University Press. This book was released on 1988-04-14 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt: A current account of quasar astronomy that not only summarizes existing results from various techniques but refers to the potentialities of new instruments. All aspects of quasar spectroscopy are discussed and techniques for analyzing quasar data are summarized.
Download or read book A Faint Spectroscopic Quasar Survey microform written by David Joseph Schade and published by National Library of Canada = Bibliothèque nationale du Canada. This book was released on 1990 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Study of the Optical and X ray Properties of Quasars written by Steven Ever Bradley and published by . This book was released on 1985 with total page 290 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Small Galaxy Group Mergers and Quasars written by Seppo Wirén and published by . This book was released on 2000 with total page 151 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 Disc Winds Matter written by James Matthews and published by Springer. This book was released on 2017-08-01 with total page 243 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis describes the application of a Monte Carlo radiative transfer code to accretion disc winds in two types of systems spanning 9 orders of magnitude in mass and size. In both cases, the results provide important new insights. On small scales, the presence of disc winds in accreting white dwarf binary systems has long been inferred from the presence of ultraviolet absorption lines. Here, the thesis shows that the same winds can also produce optical emission lines and a recombination continuum. On large scales, the thesis constructs a simple model of disc winds in quasars that is capable of explaining both the observed absorption and emission signatures – a crucial advance that supports a disc-wind based unification scenario for quasars. Lastly, the thesis also includes a theoretical investigation into the equivalent width distribution of the emission lines in quasars, which reveals a major challenge to all unification scenarios.
Download or read book Some Aspects of the Radio Morphology of Quasars with Z written by John Robin Price and published by National Library of Canada. This book was released on 1989 with total page 388 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Optical Brightness and Polarization of Quasars and Related Objects written by Ben Quiller McGimsey and published by Palala Press. This book was released on 2015-09-09 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work. This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Download or read book Optical Brightness and Polarization of Quasars and Related Objects written by Ben Quiller McGimsey and published by Palala Press. This book was released on 2018-02-19 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work. This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work. As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.
Download or read book The Space Distribution of Quasars written by David Crampton and published by . This book was released on 1991 with total page 432 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Abstracts of Theses for Masters Degrees and Titles of Doctoral Dissertations written by Vanderbilt University and published by . This book was released on 1978 with total page 530 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Glimpsing an Invisible Universe written by Richard F. Hirsh and published by CUP Archive. This book was released on 1983-10-13 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book deals with the evolution of X-ray astronomy during the initial phases of its development. Three transformations of astronomy as a discipline are highlighted: the augmentation of purely optical observations; the emergence of federal funding as the dominant source of financial support; and the greatly altered size and structure of the research community.
Download or read book A Survey for Quasars with Redshifts Greater Than Four written by Shelley Raye Lemley and published by . This book was released on 1998 with total page 434 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 652 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Download or read book On the Nature and Origin of the Broad Line Region in QSOs and Seyfert 1 Galaxies written by Michael Mauro De Robertis and published by . This book was released on 1983 with total page 652 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book To Quarks and Quasars written by Robert T. Lagemann and published by . This book was released on 2000 with total page 616 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Quasars written by Franz Daniel Kahn and published by Manchester University Press. This book was released on 1967 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt:
