Download or read book The X ray Background written by Xavier Barcons and published by Cambridge University Press. This book was released on 1992-07-31 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt: A review of the current observational knowledge and understanding of the cosmic X-ray background.
Download or read book Active Galactic Nuclei written by Julian H. Krolik and published by Princeton University Press. This book was released on 2021-03-09 with total page 632 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the first comprehensive treatment of active galactic nuclei--the cosmic powerhouses at the core of many distant galaxies. The term active galactic nuclei refers to quasars, radio galaxies, Seyfert galaxies, blazars, and related objects, all of which are believed to share a similar central engine--a supermassive black hole many times the mass of the Sun. Astrophysicists have studied these phenomena for the past several decades and have begun to develop a consensus about many of their properties and internal mechanisms. Julian Krolik, one of the world's leading authorities on the subject, sums up leading ideas from across the entire range of research, making this book an invaluable resource for astronomers, physicists interested in applications of the theory of gravitation, and graduate students. Krolik begins by addressing basic questions about active galactic nuclei: What are they? How can they be found? How do they evolve? He assesses the evidence for massive black holes and considers how they generate power by accretion. He discusses X-ray and g-ray emission, radio emission and jets, emission and absorption lines, anisotropic appearance, and the relationship between an active nucleus and its host galaxy. He explores the mysteries of what ignites, fuels, and extinguishes active galactic nuclei, and concludes with a general review of where the field now stands. The book is unique in paying careful attention to relevant physics as well as astronomy, reflecting in part the importance of general relativity to understanding active galactic nuclei. Clear, authoritative, and detailed, this is crucial reading for anyone interested in one of the most dynamic areas of astrophysics today.
Download or read book The X ray Universe written by Wallace H. Tucker and published by . This book was released on 1985 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt: Beyond the range of optical perception--and of ordinary imaginings--a new and violent universe lay undetected until the advent of space exploration. Supernovae, black holes, quasars and pulsars--these were the secrets of the highenergy world revealed when, for the first time, astronomers attached their instruments to rockets and lofted them beyond the earth's x-ray-absorbing atmosphere. The X-Ray Universe is the story of these explorations and the fantastic new science they brought into being. It is a first-hand account: Riccardo Giacconi is one of the principal pioneers of the field, and Wallace Tucker is a theorist who worked closely with him at many critical periods. The book carries the reader from the early days of the Naval Research Laboratory through the era of V-2 rocketry, Sputnik, and the birth of NASA, to the launching of the Einstein X-Ray Observatory. But this is by no means just a history. Behind the suspenseful, sometimes humorous details of human personality grappling with high technology lies a sophisticated exposition of current cosmology and astrophysics, from the rise and fall of the steady-state theory to the search for the missing mass of the universe.
Download or read book Handbook of X ray and Gamma ray Astrophysics written by Cosimo Bambi and published by Springer Nature. This book was released on with total page 5912 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 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 Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 702 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Populations of High Energy Sources in Galaxies IAU S230 written by International Astronomical Union. Symposium and published by Cambridge University Press. This book was released on 2006-06-15 with total page 520 pages. Available in PDF, EPUB and Kindle. Book excerpt: For the last 40 years astronomers have observed sources of intense X-ray radiation from beyond our Solar System. These have been associated with remarkable objects, such as neutron stars and black holes. Current satellite observatories have enabled us to extend the studies of these objects from the Milky Way and Magellanic Clouds to individual X-ray sources in other galaxies. At the same time, imaging facilities at gamma-rays and TeV energies have improved enormously, leading to many further discoveries within our own galaxy. This Symposium presents an overview of these new developments, covering detailed studies of individual sources within the Milky Way, global descriptions of X-ray source populations in other galaxies, and less resolved relatives at high redshift. Galaxy nuclei and diffuse emission components are included, as are new discoveries at gamma-rays and TeV energies. IAU S230 is a valuable resource for astronomers and graduates working in high-energy astrophysics.
Download or read book Supermassive Black Holes in the Distant Universe written by A.J. Barger and published by Springer Science & Business Media. This book was released on 2004-08-03 with total page 322 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quasars, and the menagerie of other galaxies with "unusual nuclei", now collectively known as Active Galactic Nuclei or AGN, have, in one form or another, sparked the interest of astronomers for over 60 years. The only known mechanism that can explain the staggering amounts of energy emitted by the innermost regions of these systems is gravitational energy release by matter falling towards a supermassive black hole --- a black hole whose mass is millions to billions of times the mass of our Sun. AGN emit radiation at all wavelengths. X-rays originating at a distance of a few times the event horizon of the black hole are the emissions closest to the black hole that we can detect; thus, X-rays directly reveal the presence of active supermassive black holes. Oftentimes, however, the supermassive black holes that lie at the centers of AGN are cocooned in gas and dust that absorb the emitted low energy X-rays and the optical and ultraviolet light, hiding the black hole from view at these wavelengths. Until recently, this low-energy absorption presented a major obstacle in observational efforts to map the accretion history of the universe. In 1999 and 2000, the launches of the Chandra and XMM-Newton X-ray Observatories finally broke the impasse. The impact of these observatories on X-ray astronomy is similar to the impact that the Hubble Space Telescope had on optical astronomy. The astounding new data from these observatories have enabled astronomers to make enormous advances in their understanding of when accretion occurs.
Download or read book Cosmic Magnetism written by Percy Seymour and published by CRC Press. This book was released on 1986 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of extraterrestrial magnetic fields is a relatively new one, confirmation of the existance of the first such field (that of our Sun) having come a s late as 1908. In the past 30 years a great ammount of knowledge has been accumulated on Cosmic Magnetism, which has turned out to be a truly fascinating topic for study. Percy Seymour's book is the first to deal with the topic in a non-mathematical way, and he offers a fine introduction to his subject. The first three chapters consolidate our knowledge on magnetism in general and the magnetic field of the Earth, as well as discussing the reasons for studying astronomy and cosmic magnetism in particular. The remainder of the book is devoted to the main areas of cosmic magnetism - solar, plantetary and interplanetary fields, fields in stars and pulsars, fields of the milky way and fields in other galaxies. Cosmic Magnetism in an ideal book for sixth-formers and undergraduates studying physics or astronomy and will also appeal to amateur astronomers. as previous work on this topic has been 'hidden' in specialised academic journals.
Download or read book Active Galactic Nuclei written by Volker Beckmann and published by John Wiley & Sons. This book was released on 2013-08-29 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 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 Learning from Imbalanced Data Sets written by Alberto Fernández and published by Springer. This book was released on 2018-10-22 with total page 385 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a general and comprehensible overview of imbalanced learning. It contains a formal description of a problem, and focuses on its main features, and the most relevant proposed solutions. Additionally, it considers the different scenarios in Data Science for which the imbalanced classification can create a real challenge. This book stresses the gap with standard classification tasks by reviewing the case studies and ad-hoc performance metrics that are applied in this area. It also covers the different approaches that have been traditionally applied to address the binary skewed class distribution. Specifically, it reviews cost-sensitive learning, data-level preprocessing methods and algorithm-level solutions, taking also into account those ensemble-learning solutions that embed any of the former alternatives. Furthermore, it focuses on the extension of the problem for multi-class problems, where the former classical methods are no longer to be applied in a straightforward way. This book also focuses on the data intrinsic characteristics that are the main causes which, added to the uneven class distribution, truly hinders the performance of classification algorithms in this scenario. Then, some notes on data reduction are provided in order to understand the advantages related to the use of this type of approaches. Finally this book introduces some novel areas of study that are gathering a deeper attention on the imbalanced data issue. Specifically, it considers the classification of data streams, non-classical classification problems, and the scalability related to Big Data. Examples of software libraries and modules to address imbalanced classification are provided. This book is highly suitable for technical professionals, senior undergraduate and graduate students in the areas of data science, computer science and engineering. It will also be useful for scientists and researchers to gain insight on the current developments in this area of study, as well as future research directions.
Download or read book Energy Research Abstracts written by and published by . This book was released on 1990 with total page 834 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Literature 1997 Part 1 written by Astronomisches Rechen-InstitutARI and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 1746 pages. Available in PDF, EPUB and Kindle. Book excerpt: Astronomy and Astrophysics Abstracts is devoted to the recording, summarizing and indexing of astronomical publications throughout the world. Two volumes are scheduled to appear per year. Volume 67 records 10,903 papers covering besides the classical fields of astronomy and astrophysics such matters as space flights related to astronomy, lunar and planetary probes and satellites, meteorites and interplanetary matter, X rays and cosmic rays, quasars and pulsars. The abstracts are classified under more than one hundred subject categories thus permitting quick surveying of the bulk of material published on the same topic within six months. For instance, this volume records 119 papers on minor planets, 155 papers on supernovae, and 554 papers on cosmology.
Download or read book Literature 1991 Part 2 written by Astronomisches Rechen-Institut and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 1592 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Astronomy and Astrophysics Abstracts" appearing twice a year has become oneof the fundamental publications in the fields of astronomy, astrophysics andneighbouring sciences. It is the most important English-language abstracting journal in the mentioned branches. The abstrats are classified under more than a hundred subject categories, thus permitting a quick survey of the whole extended material. The AAA is a valuable and important publication for all students and scientists working in the fields of astronomy and related sciences. As such it represents a necessary ingredient of any astronomical library all over the world.
Download or read book The New Era of Wide Field Astronomy written by IAU Commission 9. Working Group on Sky Surveys and published by . This book was released on 2001 with total page 520 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent research in wide-field astronomy is reported in these papers from an August 2000 conference, encompassing theoretical developments as well as innovations in observational instrumentation. Advances in wide-field cosmology and extragalactic astronomy, wide-field galactic astronomy, wide-field planetary astronomy, databases and access, new telescopes and instruments, and new surveys are detailed. There is also material on the wide-field photographic legacy. Some specific topics are the Chandra Multi-wavelength Project, cosmology of the space-luminosity distribution of virialized halos, galaxy formation at high redshifts, the faint sky variability survey, saving astronomical treasures, and searching for NEOs using wide-field telescopes. Annotation copyrighted by Book News Inc., Portland, OR.
