Download or read book Radio AGN Evolution with Low Frequency Radio Surveys written by Louise Moira Ker and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NgVLA written by Eric James Murphy and published by . This book was released on 2018 with total page 830 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Low frequency Radio Universe written by Homi Jehangir Bhabha and published by . This book was released on 2009 with total page 504 pages. Available in PDF, EPUB and Kindle. Book excerpt: A strong resurgence of interest in low-frequency radio astronomy in the past few decades has led to addressing many of the outstanding and challenging astrophysical and technical problems and issues. The GMRT has been in operation for close to a decade. Early results have been reported from LOFAR. The next generation of telescopes such as the LWA, MWA, MeerKAT, ASKAP and SKA should provide exciting challenges, results, and opportunities. To discuss recent results and astrophysical problems as well as a range of technical issues at low radio frequencies, a conference and workshop was held at the National Centre for Radio Astrophysics of the Tata Institute of Fundamental Research. This event commemorated the birth centenary of Dr. Homi J. Bhabha, who contributed immensely in both the sciences and the arts. There were approximately 130 participants from over a dozen countries. The conference brought together experts with a wide range of interests from major observatories and institutions across the world as well as younger research workers largely from within India. There were over 100 papers presented, including several extensive reviews, on a large variety of topics including low-frequency surveys and cosmology, extragalactic neutral hydrogen and OH, extragalactic radio sources, clusters of galaxies, our Galaxy, pulsars, transients and high-energy sources, Sun and planetary studies, and instrumentation and techniques. The book provides an overview of research at low radio frequencies and should be of interest to a wide spectrum of students and researchers.
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 The Master Sample written by United States. Bureau of Agricultural Economics and published by . This book was released on 1946 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Probing Galaxy Evolution Through Deep Radio Continuum Observations written by Hansung Gim and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the most important questions in modern astrophysics is how galaxies form and evolve. There are numerous processes involved in galaxy evolution, but the stellar mass buildup and supermassive black hole growth are two main drivers in galaxy evolution. Those activities are heavily obscured by dust, so we need another tracer without dust attenuation: low-frequency radio continuum observation. We understand the galaxy evolution through the deep radio continuum observations on the Great Observatories Origins Deep Survey (GOODS)-North, -South, and the COSMOS HI Large Extragalactic Survey (CHILES) fields. Exploiting the multi-wavelength dataset, we define the radio populations such as star-formation (SF) dominated, active galactic nuclei (AGN)-dominated, and passive galaxies by applying new selection criteria. Populations are defined according to the relative contributions of SF and AGN luminosities to the bolometric luminosities of host galaxies and star formation properties. We explore the physical properties of radio populations, interpret their properties in the context of galaxy evolution, and show that our results of radio populations are consistent with the galaxy evolution scenarios. These results are the same for the GOODS and CHILES fields. Our investigation of the radio spectral index and radio-FIR correlation for the GOODS fields show that the radio spectral index is characteristic of each population and the radio-FIR correlation is a robust tracer of star formation activity. The analysis of radio spectral index shows the prominence of steep spectrum sources at faint flux density first as expected in the Euclidean normalized number counts. We also show that the radio spectral index should be calculated by matching the beam sizes of images. The evolution of the radio-FIR correlation in SF-dominated galaxies is not found significantly with our data. On the other hand, the analysis of radio spectral index for the CHILES is not consistent with the result of the GOODS due to the larger difference of beam area. This inconsistency gives important implications for the future works.
Download or read book Galaxies and Cosmology written by Francoise COMBES and published by Springer Science & Business Media. This book was released on 2004-08-11 with total page 468 pages. Available in PDF, EPUB and Kindle. Book excerpt: Unique in its breadth of coverage and level of presentation, this revised textbook provides more on the nature of galaxies, extragalactic objects, the large-scale structure of the Universe, and cosmology than is available in general textbooks on astronomy. It remains, however, accessible to advanced undergraduate students. One or more chapters are devoted to each of the following: the classification and morphology of galaxies; the galactic interstellar medium; galactic kinematics; elliptical, spiral, and barred spiral galaxies; the interactions between galaxies; extragalactic radio sources, quasars and their line spectra, and other active galactic nuclei; the formation of galaxies; the Universe as a whole; and cosmology.
Download or read book The Universe at Low Radio Frequencies written by International Astronomical Union. Symposium and published by . This book was released on 2002 with total page 560 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Formation and Disruption of Black Hole Jets written by Ioannis Contopoulos and published by Springer. This book was released on 2014-11-10 with total page 273 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book reviews the phenomenology displayed by relativistic jets as well as the most recent theoretical efforts to understand the physical mechanisms at their origin. Relativistic jets have been observed and studied in Active Galactic Nuclei (AGN) for about half a century and are believed to be fueled by accretion onto a supermassive black hole at the center of the host galaxy. Since the first discovery of relativistic jets associated with so-called "micro-quasars" much more recently, it has seemed clear that much of the physics governing the relativistic outflows in stellar X-ray binaries harboring black holes and in AGN must be common, but acting on very different spatial and temporal scales. With new observational and theoretical results piling up every day, this book attempts to synthesize a consistent, unified physical picture of the formation and disruption of jets in accreting black-hole systems. The chapters in this book offer overviews accessible not only to specialists but also to graduate students and astrophysicists working in other areas. Covered topics comprise Relativistic jets in stellar systems Launching of AGN jets Parsec-scale AGN jets Kiloparsec-scale AGN jets Black hole magnetospheres Theory of relativistic jets The structure and dynamics of the inner accretion disk The origin of the jet magnetic field X-ray observations, phenomenology, and connection with theory
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 Advancing astrophysics with the square kilometre array proceedings from a meeting held in Giardini Naxos Sicily Italy 9 13 June 2014 written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book New Horizons from Multi Wavelength Sky Surveys written by International Astronomical Union. Symposium and published by Springer Science & Business Media. This book was released on 1998-01-31 with total page 548 pages. Available in PDF, EPUB and Kindle. Book excerpt: Scientists share their experience making surveys of large parts of the sky in the various wavelengths of radio, infrared, optical, and x-ray passbands, and using the mosaic cameras with high throughput digital detectors that are expected to come on line in the next few years for optical, infrared, and ultraviolet surveys. Some 120 papers cover reviews of general sky surveys, specific survey projects, the interstellar medium, galactic structure, extra-galactic astronomy, large-scale structure, data processing techniques, catalogues, multi-wavelength cross identification, and databases. Resolutions generated by the conference are also listed and discussed. No subject index. Annotation copyrighted by Book News, Inc., Portland, OR
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 Literature 1986 Part 1 written by Prof. Dr. Roland Wielen and published by Springer Science & Business Media. This book was released on 2013-04-17 with total page 1122 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Astronomical Data Analysis Software and Systems XIV written by Patrick L. Shopbell and published by . This book was released on 2005 with total page 776 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Square Kilometre Array Paving the way for the new 21st century radio astronomy paradigm written by Domingos Barbosa and published by Springer Science & Business Media. This book was released on 2012-01-11 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt: : The Square Kilometre Array (SKA) will provide more than one order of magnitude improvement in sensitivity compared with any existing radio telescope over a wavelength range of several hundred to one, from decametric to microwave wavelengths. It will revolutionize the study of the most abundant element in the Universe, hydrogen, from the epoch of reionisation to the present-day, probing the onset formation period of the very first stars, will closely scan proto-planets and, through the precision timing of pulsars, will detect the distortions of space-time due to gravitational radiation. The SKA is a sensing network spanning 3000 km from its centre and with a collecting area of more than 1 square kilometre, using technologies of the 21st century. The SKA will make the study of a wide range of phenomena initially studied at other wavelengths possible at radio wavelengths, as well as opening a new discovery window on new phenomena at radio wavelengths. Symposium 7 of the JENAM 2010 aimed at bringing these diverse opportunities to the attention of both theoretical and observational astronomers working at all wavelengths, including the potential for synergies with other facilities. The meeting highlighted the scientific potential of the SKA, discussed scientific priorities and their impact on the design of the SKA, explored the synergies between the SKA and other next-generation astronomical facilities in different wavelength domains such as the ALMA, ELTs, LSST, JWST, GRE, IXO, Gaia and Euclid, and high-energy facilities (Auger), explored the “cyber–infrastructure” that may become available for the distribution and distributed analysis of SKA data.
Download or read book Radio AGN Surveys written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We present a short overview of radio surveys for AGN, including the ''complete'' flux limited surveys and ''filtered'' surveys. We also describe our ultra-steep spectrum search for the highest redshift radio galaxies, and our follow-up VLA and ATCA observations of the most distant (z = 5.19) and the most luminous z
