Download or read book Molecular Clouds and Galactic Spiral Structure written by Thomas M. Dame and published by . This book was released on 1984 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Molecular Clouds in the Milky Way and External Galaxies written by Robert L. Dickman and published by Springer. This book was released on 2013-11-20 with total page 475 pages. Available in PDF, EPUB and Kindle. Book excerpt: The volume consists of up-to-date reviews and a selection of contributed papers on subjects including the structure and physical properties of molecular clouds, their role in the star formation process, their dust and chemical properties, molecular cloud surveys of the Milky Way, cloud evolution, problems in cloud mass determinations (a panel discussion and review), the CO properties of external galaxies, nuclei of galaxies as revealed by molecular observations, and galactic spiral structure as reflected by molecular cloud distributions. The abstracts of poster papers on these topics presented at the conference are also included. This book is both a valuable reference and a compendium of current knowledge in this field. It should be of special interest to all students and researchers who work on the physics of star formation, the interstellar medium, molecular clouds and galactic structure.
Download or read book Molecular Clouds in the Milky Way and External Galaxies written by Robert L. Dickman and published by . This book was released on 1988 with total page 504 pages. Available in PDF, EPUB and Kindle. Book excerpt: The volume consists of up-to-date reviews and a selection of contributed papers on subjects including the structure and physical properties of molecular clouds, their role in the star formation process, their dust and chemical properties, molecular cloud surveys of the Milky Way, cloud evolution, problems in cloud mass determinations (a panel discussion and review), the CO properties of external galaxies, nuclei of galaxies as revealed by molecular observations, and galactic spiral structure as reflected by molecular cloud distributions. The abstracts of poster papers on these topics presented at the conference are also included. This book is both a valuable reference and a compendium of current knowledge in this field. It should be of special interest to all students and researchers who work on the physics of star formation, the interstellar medium, molecular clouds and galactic structure.
Download or read book The Distribution of Molecular Clouds in Spiral Galaxies written by David Scott Adler and published by . This book was released on 1989 with total page 470 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dynamics of Galaxies and Their Molecular Cloud Distributions written by F. Combes and published by Springer Science & Business Media. This book was released on 1991-01-31 with total page 514 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of the 146th Symposium of the International Astronomical Union, held in Paris, France, June 4-9, 1990
Download or read book Molecular Clouds as Probes of Milky Way Structure and Interstellar Turbulence written by Julia Duval and published by . This book was released on 2010 with total page 536 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: The Galactic Ring Survey, a 13 CO survey of the first quadrant of the Milky Way, is used to probe the spiral structure of the Galaxy and to constrain the formation and turbulent structure of molecular clouds. A sample of 829 molecular clouds has been identified in the Galactic Ring Survey (GRS). Kinematic distances to 750 of these GRS clouds are derived. The Galactic surface mass density of molecular gas is subsequently computed from 13 CO and 12 CO emission detected in the GRS and the University of Massachusetts-Stony Brook surveys. The Galactic distribution of molecular clouds is strongly enhanced along the Scutum-Crux, Sagittarius, and Perseus arms. These molecular data are consistent with a four-arm model of the Galaxy, while the locations of the Scutum-Crux and Perseus arms are consistent with the distribution of the old stellar population inferred from infrared maps. Physical properties of molecular clouds such as size, mass, and density, are also derived in order to compare clouds located inside and outside spiral arms, and to constrain formation models. Molecular clouds located inside inferred spiral arms are found to be more massive, to have higher surface mass densities, and to be more strongly gravitationally bound than inter-arm clouds. This supports cloud formation models involving spiral structure and suggests that molecular clouds must have lifetimes of a few million years. The turbulent structure of molecular clouds is a fundamental component of star formation. The GRS is the first large scale, fully sampled 13 CO survey of the Galaxy allowing the observation of the sub-parsec-scale structure of molecular clouds. Principal Component Analysis applied to both GRS clouds and numerical simulations allows the derivation of turbulent energy spectra over scales ranging from 0.1 pc to 50 pc. The slope of the energy spectrum, E(k), versus the wavenumber, k, obtained for the GRS clouds is consistent with compressible, intermittent turbulence. The slopes and amplitudes of the energy spectra of the clouds are fairly constant over three decades of masses, which indicates that turbulence is driven on large scales by an external, Galactic pool of kinetic energy.
Download or read book The Formation of Molecular Clouds in Spiral Galaxies written by Clare Louise Dobbs and published by . This book was released on 2007 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Implications of collisionally supported giant molecular clouds for spiral galactic structure and massive star formation written by David Todd Leisawitz and published by . This book was released on 1981 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Giant Molecular Clouds in the Galaxy written by P. M. Solomon and published by Elsevier. This book was released on 2013-10-22 with total page 361 pages. Available in PDF, EPUB and Kindle. Book excerpt: Giant Molecular Clouds in the Galaxy: Third Gregynog Astrophysics Workshop covers the proceedings of the 1977 Third Gregynog Astrophysics Workshop on Giant Molecular Clouds (GMC), held at the University of Wales. This book is organized into 11 parts encompassing 33 chapters. After a brief introduction to the significant features of GMC, this book goes on examining radio, millimeter, and galactic center observations of GMC, along with their infrared properties and kinematics. Other parts deal with the water sources in GMC; time variation in interstellar water masers; and the relation of HII regions to molecular clouds. The remaining parts discuss the evolution of interstellar molecular clouds and the role of magnetic fields in the collapse of protostellar gas clouds. These parts also cover the chemistry of interstellar molecules containing nitrogen and the search for other planetary systems. This book will prove useful to cloud scientists, physicists, astronomers, and researchers.
Download or read book Gas Distribution Star Formation and Giant Molecular Cloud Evolution in Nearby Spiral Galaxies written by 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 The Mapping and Modelling of Spiral Structure in the Milky Way written by Lee James Summers and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: It was in 1864 that the first clues as to the nature of the space between stars were firstidentified in literature. These spaces became known as the interstellar medium. Any study of star formation must include an understanding of this interstellar medium (ISM) and its various component parts. Molecular clouds, dense regions of the ISM, are the sites where all known star formation is thought to occur. Hence, whenever an area containing young stars reside, it is assumed that one will also find a molecular cloud. Knowledge of these stellar birthplaces assist not only in models of stellar evolution, star formation potential, rate and efficiency - but also the ISM gives indications as to Galactic structure and the dynamics therein. Within this thesis I begin with an introduction and historical background of the field before detailing the research which was conducted. Firstly, I discuss a new model describing the spatial and kinematic structure of the Milky Way's spiral potentials; the Perseus arm, the Outer arm and the outer Scutum-Centaurus arm and also the kinematics of the streaming motions of the gas within them. Material associated with each of these arms is then extracted. Using the models and spiral arm maps derived, I present spatially convolved maps of each spiral arm region (Perseus, Outer and Scutum-Centaurus) at a constant linear scale. By minimising the biases inherent with angular observations of our Galaxy, this presents the data as an analogue of - and as such directly comparable to - extragalactic observations of spiral structure. Finally I present a series of analyses performed on the data and models; derivation of large-scale properties of the spiral arms (i.e. identification of where the arm is unconfused with fore- and back-ground emission, scale height, velocity dispersions, arm mass); dynamical analyses of the models; molecular cloud decomposition of the constant-linear-scale-maps. The findings are then compared with those in the Galactic and extra-galactic literature.
Download or read book HI Self absorption Clouds and Related Studies of Spiral Structures written by Frank Howard Levinson and published by . This book was released on 1980 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Galactic and Extragalactic Star Formation written by Ralph E. Pudritz and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 652 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent advances in the instrumentation used to observe star forming regions in both our own Milky Way and in external galaxies have transformed the subject from a phenomenological pursuit into an increasingly unified, physical science. High resolution centimetre, millimetre, infrared, and optical studies of local star forming clouds have allowed us to probe the physics of star formation down to spatial scales approaching those of the solar system. These developments make it possible to better constrain the basic physical processes underlying star formation itself. At the same time, these new instruments have placed extragalactic studies on a footing detailed enough to allow comparison with star forming regions within our own galaxy. This revolution means that we will soon be able to link the physics of local star forming regions to the global star forming properties of galaxies. The entire structure of this NATO Advanced Study Institute was designed to explore this new view of the subject. This Institute on "Galactic and Extragalactic Star Formation" was held from June 21 -July 4, 1987 at the Conference Centre in the village of Whistler, British Columbia, Canada. The informal atmosphere of this lovely mountain resort stim ulated many valuable scientific exchanges. The Institute was funded by a major grant from NATO Scientific Affairs. Additional financial and I.I1oral assistance was provided by the Canadian Institute for Theoretical Astrophysics (CITA) and Mc Master University.
Download or read book Spiral Structure in Galaxies written by Marc S Seigar and published by Morgan & Claypool Publishers. This book was released on 2017-06-29 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt: How does it happen that billions of stars can cooperate to produce the beautiful spirals that characterize so many galaxies, including ours? This book reviews the history behind the discovery of spiral galaxies and the problems faced when trying to explain the existence of spiral structure within them. In the book, subjects such as galaxy morphology and structure are addressed as well as several models for spiral structure. The evidence in favor or against these models is discussed. The book ends by discussing how spiral structure can be used as a proxy for other properties of spiral galaxies, such as their dark matter content and their central supermassive black hole masses, and why this is important.
Download or read book Spiral Structure in Galaxies written by Giuseppe Bertin and published by MIT Press. This book was released on 1996 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: How does it happen that billions of stars can cooperate to produce the beautiful spirals that characterize so many galaxies, including ours? This book presents a theory of spiral structure that has been developed over the past three decades under the continuous stimulus of new observational studies. The theory unfolds in a way that can be grasped by any reader with an undergraduate science background who is interested in astronomy, as well as by graduate students and scientists actively involved in astronomy or related subjects who want to see the "backbone" and the physical content of the theory. The foundations of this theoretical framework were laid in the early 1960s, following the pioneering work of B. Lindblad. C. C. Lin had already contributed significantly to the field of fluid mechanics when he turned his attention to spiral structures, and he has focused on the problem ever since. Giuseppe Bertin joined this research effort when he first visited at MIT in 1975, bringing to the project knowledge from his work on elliptical galaxies and plasma astrophysics. Together, Bertin and Lin have contributed to the exciting developments on spiral structure of the last few decades, working closely with many observers and other theorists. In this book they describe the density-wave theory with the goal of making the key concepts and astrophysical implications explicit and accessible. The essence of the solution Bertin and Lin present is that the spirals are wave rather than material phenomena and generally trace intrinsic characteristics of the individual galaxies. The book is in three parts--Physical Concepts, Observational Studies, and Dynamical Mechanisms--with most of the technical details confined to the last part.
Download or read book Global Studies of Molecular Clouds in the Galaxy the Magellanic Clouds and M31 written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2018-09-25 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the course of this grant we used various spacecraft surveys of the Galaxy and M31 in conjunction with our extensive CO spectral line surveys to address central problems in galactic structure and the astrophysics of molecular clouds. These problems included the nature of the molecular ring and its relation to the spiral arms and central bar, the cosmic ray distribution, the origin of the diffuse X-ray background, the distribution and properties of x-ray sources and supernova remnants, and the Galactic stellar mass distribution. For many of these problems, the nearby spiral M31 provided an important complementary perspective. Our CO surveys of GMCs (Galactic Molecular Clouds) were crucial for interpreting Galactic continuum surveys from satellites such as GRO (Gamma Ray Observatory), ROSAT (Roentgen Satellite), IRAS (Infrared Astronomy Satellite), and COBE (Cosmic Background Explorer Satellite) because they provided the missing dimension of velocity or kinematic distance. GMCs are a well-defined and widespread population of objects whose velocities we could readily measure throughout the Galaxy. Through various emission and absorption mechanisms involving their gas, dust, or associated Population I objects, GMCs modulate the galactic emission in virtually every major wavelength band. Furthermore, the visibility. of GMCs at so many wavelengths provided various methods of resolving the kinematic distance ambiguity for these objects in the inner Galaxy. Summaries of our accomplishments in each of the major wavelength bands discussed in our original proposal are given Thaddeus, Patrick Goddard Space Flight Center
