Download or read book Accretion and Winds written by Gerhard Klare and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt: In order to bring the scientific events of the meetings of the Astronomische Gesellschaft (AG) to the attention of the worldwide astronomical community, an annual publication, Reviews in Modern Astronomy, was established. It is devoted exclusively to . the invited reviews, the Karl Schwarz schild lectures, and the high light contributions from leading scientists reporting on recent progress and scientific achievements at their respective institutes. This third volume continues the yearbook series of publications of the society. It comprises the complete set of contributions presented during the spring meeting of the AG at Berlin in March 1990, which was dedicated to the topic "Accretion and Winds". In addition four latecomers (two review and two highlight papers) delivered at the fall meeting at Graz, Austria in September 1989 close this volume. Heidelberg, September 1990 G: Klare Contents Some New Elements in Accretion Disk Theory By F. Meyer (With 5 Figures) . . . . . . . . . . . . . . . . . . . . . . . 1 Mass Transfer and Evolution in Close Binaries By A. R. King (With 4 Figures) . . . . . . . . . . . . . . . . . . . . . . . 14 Radiation Hydrodynamics of the Boundary Layer of Accretion Disks in Cataclysmic Variables By W. Kley (With 6 Figures) . . . . . . . . . . . . . . . . . . . . . . . . 21 Curious Observations of Cataclysmic Variables By F. V. Hessman (With 10 Figures) . . . . . . . . . . . . . . . . . . . 32 Accretion in AM Herculis Stars 44 By A. D. Schwope (With 12 Figures) X-ray Diagnostics of Accretion Disks By G. Hasinger (With 12 Figures) . . . . . . . . . . . . . . . . . . . . . 60 Accretion Phenomena at Neutron Stars By A. Rebetzky, H. Herold, U. Kraus, H. -P. Nollert, and H. Ruder (With 13 Figures) . . . . . . . . . . . . . . . . . . . . . .
Download or read book MHD Flows in Compact Astrophysical Objects written by Vasily S. Beskin and published by Springer Science & Business Media. This book was released on 2009-12-08 with total page 425 pages. Available in PDF, EPUB and Kindle. Book excerpt: Accretion flows, winds and jets of compact astrophysical objects and stars are generally described within the framework of hydrodynamical and magnetohydrodynamical (MHD) flows. Analytical analysis of the problem provides profound physical insights, which are essential for interpreting and understanding the results of numerical simulations. Providing such a physical understanding of MHD Flows in Compact Astrophysical Objects is the main goal of this book, which is an updated translation of a successful Russian graduate textbook. The book provides the first detailed introduction into the method of the Grad-Shafranov equation, describing analytically the very broad class of hydrodynamical and MHD flows. It starts with the classical examples of hydrodynamical accretion onto relativistic and nonrelativistic objects. The force-free limit of the Grad-Shafranov equation allows us to analyze in detail the physics of the magnetospheres of radio pulsars and black holes, including the Blandford-Znajek process of energy extraction from a rotating black hole immersed in an external magnetic field. Finally, on the basis of the full MHD version of the Grad-Shafranov equation the author discusses the problems of jet collimation and particle acceleration in Active Galactic Nuclei, radio pulsars, and Young Stellar Objects. The comparison of the analytical results with numerical simulations demonstrates their good agreement. Assuming that the reader is familiar with the basic physical and mathematical concepts of General Relativity, the author uses the 3+1 split approach which allows the formulation of all results in terms of physically clear language of three dimensional vectors. The book contains detailed derivations of equations, numerous exercises, and an extensive bibliography. It therefore serves as both an introductory text for graduate students and a valuable reference work for researchers in the field.
Download or read book Accretion and Winds written by Gerhard Klare and published by Springer Verlag. This book was released on 1990 with total page 370 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Clumping in Hot star Winds written by Wolf-Rainer Hamann and published by Universitätsverlag Potsdam. This book was released on 2008 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Accretion and Winds written by and published by . This book was released on 1990 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Accretion Processes in Star Formation written by Lee Hartmann and published by Cambridge University Press. This book was released on 2000-11-15 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt: This first comprehensive account of the dynamical processes in the formation of stars and disks from which planets ultimately form.
Download or read book The structure and appearance of winds from supercritical accretion disks written by and published by . This book was released on 1977 with total page 338 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Physics of Wind Fed Accretion written by and published by . This book was released on 2008 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: We provide a brief review of the physical processes behind the radiative driving of the winds of OB stars and the Bondi-Hoyle-Lyttleton capture and accretion of a fraction of the stellar wind by a compact object, typically a neutron star, in detached high-mass X-ray binaries (HMXBs). In addition, we describe a program to develop global models of the radiatively-driven photoionized winds and accretion flows of HMXBs, with particular attention to the prototypical system Vela X-1. The models combine XSTAR photoionization calculations, HULLAC emission models appropriate to X-ray photoionized plasmas, improved models of the radiative driving of photoionized winds, FLASH time-dependent adaptive-mesh hydrodynamics calculations, and Monte Carlo radiation transport. We present two- and three-dimensional maps of the density, temperature, velocity, ionization parameter, and emissivity distributions of representative X-ray emission lines, as well as synthetic global Monte Carlo X-ray spectra. Such models help to better constrain the properties of the winds of HMXBs, which bear on such fundamental questions as the long-term evolution of these binaries and the chemical enrichment of the interstellar medium.
Download or read book The Hydrodynamics of accretion from stellar winds written by Ronald Everett Taam and published by . This book was released on 1989 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Black Hole Accretion Disks written by 加藤正二 and published by Trans Pacific Press. This book was released on 1998-02 with total page 616 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book MHD Flows in Compact Astrophysical Objects written by Vasily S. Beskin and published by Springer. This book was released on 2009-12-10 with total page 425 pages. Available in PDF, EPUB and Kindle. Book excerpt: Accretion flows, winds and jets of compact astrophysical objects and stars are generally described within the framework of hydrodynamical and magnetohydrodynamical (MHD) flows. Analytical analysis of the problem provides profound physical insights, which are essential for interpreting and understanding the results of numerical simulations. Providing such a physical understanding of MHD Flows in Compact Astrophysical Objects is the main goal of this book, which is an updated translation of a successful Russian graduate textbook. The book provides the first detailed introduction into the method of the Grad-Shafranov equation, describing analytically the very broad class of hydrodynamical and MHD flows. It starts with the classical examples of hydrodynamical accretion onto relativistic and nonrelativistic objects. The force-free limit of the Grad-Shafranov equation allows us to analyze in detail the physics of the magnetospheres of radio pulsars and black holes, including the Blandford-Znajek process of energy extraction from a rotating black hole immersed in an external magnetic field. Finally, on the basis of the full MHD version of the Grad-Shafranov equation the author discusses the problems of jet collimation and particle acceleration in Active Galactic Nuclei, radio pulsars, and Young Stellar Objects. The comparison of the analytical results with numerical simulations demonstrates their good agreement. Assuming that the reader is familiar with the basic physical and mathematical concepts of General Relativity, the author uses the 3+1 split approach which allows the formulation of all results in terms of physically clear language of three dimensional vectors. The book contains detailed derivations of equations, numerous exercises, and an extensive bibliography. It therefore serves as both an introductory text for graduate students and a valuable reference work for researchers in the field.
Download or read book Theory of Transonic Astrophysical Flows written by Sandip K. Chakrabarti and published by World Scientific. This book was released on 1990 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents methods of studying transonic flows applicable to various astrophysical circumstances. This is the first book of its kind and efforts have been made to be as thorough as possible. It gives complete mathematical solutions for the study in this area including various shock transitions. For any theoretical astrophysicists this book is expected to be very useful as the formalism discussed can be applied to all the branches. Both axisymmetric and non-axisymmetric flows are studied.
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 Accretion Power in Astrophysics written by Juhan Frank and published by Cambridge University Press. This book was released on 2002-01-17 with total page 390 pages. Available in PDF, EPUB and Kindle. Book excerpt: Accretion Power in Astrophysics examines accretion as a source of energy in both binary star systems containing compact objects, and in active galactic nuclei. Assuming a basic knowledge of physics, the authors describe the physical processes at work in accretion discs and other accretion flows. The first three chapters explain why accretion is a source of energy, and then present the gas dynamics and plasma concepts necessary for astrophysical applications. The next three chapters then develop accretion in stellar systems, including accretion onto compact objects. Further chapters give extensive treatment of accretion in active galactic nuclei, and describe thick accretion discs. A new chapter discusses recently discovered accretion flow solutions. The third edition is greatly expanded and thoroughly updated. New material includes a detailed treatment of disc instabilities, irradiated discs, disc warping, and general accretion flows. The treatment is suitable for advanced undergraduates, graduate students and researchers.
Download or read book Wind Accretion Onto Compact Objects written by Ileyk El Mellah and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: X-ray emission associated to accretion onto compact objects displays important levels of photometric and spectroscopic time-variability. When the accretor orbits a Supergiant star, it captures a fraction of the supersonic radiatively-driven wind which forms shocks in its vicinity. The amplitude and stability of this gravitational beaming of the flow conditions the mass accretion rate responsible, in fine, for the X-ray luminosity of those Supergiant X-ray Binaries (SgXB). The capacity of this low angular momentum inflow to form a disc susceptible to be the stage of instabilities remains at stake.Using state-of-the-art numerical setups, we characterize the structure of a Bondi-Hoyle- Lyttleton flow onto a compact object, from the shock down to the vicinity of the accretor, typically five orders of magnitude smaller. The evolution of the bow shock which forms around the accretor (transverse structure, opening angle, stability, temperature profile...) with the Mach number of the flow is detailed. The robustness of those simulations based on the High Performance Computing MPI-AMRVAC code is supported by the topology of the inner sonic surface, consistent with theoretical expectations.We develop a synthetic model of mass transfer in SgXB which couples the launching of the wind the stellar parameters, the orbital evolution of the streamlines and the accretion process. We show that the shape of the permanent flow is entirely determined by the filling and Eddington factor, the mass ratio and the alpha force multiplier. Provided scales are known, we can trace back, eg, the X-ray luminosity, the accretion mechanism (stream or wind-dominated) and the shearing of the inflow.
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 Black Hole Astrophysics written by David L. Meier and published by Springer Science & Business Media. This book was released on 2012-07-27 with total page 941 pages. Available in PDF, EPUB and Kindle. Book excerpt: As a result of significant research over the past 20 years, black holes are now linked to some of the most spectacular and exciting phenomena in the Universe, ranging in size from those that have the same mass as stars to the super-massive objects that lie at the heart of most galaxies, including our own Milky Way. This book first introduces the properties of simple isolated holes, then adds in complications like rotation, accretion, radiation, and magnetic fields, finally arriving at a basic understanding of how these immense engines work. Black Hole Astrophysics • reviews our current knowledge of cosmic black holes and how they generate the most powerful observed pheonomena in the Universe; • highlights the latest, most up-to-date theories and discoveries in this very active area of astrophysical research; • demonstrates why we believe that black holes are responsible for important phenomena such as quasars, microquasars and gammaray bursts; • explains to the reader the nature of the violent and spectacular outfl ows (winds and jets) generated by black hole accretion.
