Abundance Effects In Classification

Autore: B. Hauck
Editore: Springer Science & Business Media
ISBN: 9789027706751
Grandezza: 72,96 MB
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The general discussions of the roles of photometric and spectroscopic classification at Cordoba in 1971 (lAU Symposium No. 50), and of the calibration of classification indices at Geneva in 1972 (IAU Symposium No. 54), revealed clearly the steadily in creasing importance of abundance parameters. The multipliCity of these, however, raised so many new problems that it was logical that the 1975 meeting at Lausanne should be concerned with ways in which differences in abundance affect both spectral types and photometric indices. Commissions 29 and 36 joined with Commission 45 in sponsoring this Symposium. Since the date of the meeting came shortly after the formal retirement of Professor William W. Morgan from the University of Chicago, it was quickly agreed that this meeting should be dedicated to him in recognition of his unique contributions to spectral classification. In the opening paper of the Symposium Dr. Bengt Stromgren has summarized these. To his remarks we should add only that it was about 1940 that Morgan first distinguished the group of G- and K-type stars with weak CN bands and metallic lines - stars which have since been recognized as having the abundance of all metals relative to hydrogen much lower than in stars of the solar population. Spectra of two of these, HD 81192 (Boss 2527) and 8 Lep, were later shown as examples of the group in the Yerkes Atlas of 1943.

Chemical Abundances And Mixing In Stars In The Milky Way And Its Satellites

Autore: S. Randich
Editore: Springer Science & Business Media
ISBN: 3540341366
Grandezza: 43,53 MB
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This proceedings covers topics from chemical abundances in the different components of the Milky Way and in local group galaxies, via observational and theoretical papers on mixing in stars to big bang nucleosynthesis and galaxy formation and evolution. Like all volumes in the series ESO Astrophysics Symposia, this one gives a comprehensive overview of the forefront of research in this subject. It is a valuable reference for both students and researchers.

Starfish

Autore: John M. Lawrence
Editore: JHU Press
ISBN: 1421410451
Grandezza: 41,25 MB
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Vista: 8231
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Among the most fascinating animals in the world’s oceans are the more than 2,000 species of starfish. Called "Asteroids" by scientists who study them (after their taxonomic name, Asteroidea)—or sea stars in some parts of the world—starfish are easily recognized because of their star-like form. Starfish is a comprehensive volume devoted to the integrative and comparative biology and ecology of starfish. Written by the world's leading experts on starfish, the integrative section covers topics such as reproduction, developmental biology and ecology, larval ecology, and the ecological role of starfish as a group. The comparative section considers the biology and ecology of important species such as Acanthaster planci, Heliaster helianthoides, Asterias amurensis, and Pisaster ochraceus. Replete with detailed, scientifically accurate illustrations and the latest research findings, Starfish examines the important role of these invertebrates in the marine environment, a topic of great interest because of their impact on the food web. As major predators that are able to evert their stomach and wrap it around their prey, starfish can have a significant impact on commercial fisheries. Starfish are of interest not only to echinoderm specialists but also to marine biologists and invertebrate zoologists in general and, increasingly, to the medical community. A starfish’s ability to regenerate body parts is almost unequalled in the animal world, making them ideal models for basic science studies on the topic. Contributors: Charles D. Amsler, Bill J. Baker, Mario Barahona, Michael F. Barker, Maria Byrne, Juan Carlos Castilla, Katharina Fabricius, Patrick Flammang, Andrew S. Gale, Carlos F. Gaymer, Jean-François Hamel, Elise Hennebert, John H. Himmelman, Michel Jangoux, John M. Lawrence, Tatiana Manzur, James B. McClintock, Bruce A. Menge, Annie Mercier, Anna Metaxas, Sergio A. Navarette, Timothy D. O’Hara, John S. Pearse, Carlos Robles, Eric Sanford, Robert E. Scheibling, Richard L. Turner, Carlos Renato R. Ventura, Kristina M. Wasson, Stephen A. Watts

Origin And Distribution Of The Elements

Autore: L. H. Ahrens
Editore: Elsevier
ISBN: 1483158152
Grandezza: 67,39 MB
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Origin and Distribution of the Elements, Volume 30 presents detailed studies of trace elements and isotopes and the use of these data with the techniques of physical and organic chemistry to make relevant interpretations in geology. This book discusses some of the problems of applied chemistry. Organized into five sections encompassing 89 chapters, this volume begins with an overview of the theories of nucleosynthesis that are based on broad empirical foundations involving experiment in nuclear physics and observation in geophysics and astronomy. This text then explores the primeval abundance of the elements wherein the composition of the material from which the Galaxy is formed. Other chapters consider the production of helium in the galaxy. This book discusses as well the dynamics of the cores of highly evolved massive stars. The final chapter deals with the measurements of site populations in crystal structures by electron diffraction and X-ray. Physicists, astronomers, geologists, and geochemists will find this book extremely useful.

The Carbon Star Phenomenon

Autore: International Astronomical Union. Symposium
Editore: Springer Science & Business Media
ISBN: 9780792363460
Grandezza: 31,66 MB
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Proceedings of the 177th Symposium of the International Astronomical Union, held in Antalya, Turkey, May 27-31, 1996

Nuclear Science Abstracts

Autore:
Editore:
ISBN:
Grandezza: 67,78 MB
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NSA is a comprehensive collection of international nuclear science and technology literature for the period 1948 through 1976, pre-dating the prestigious INIS database, which began in 1970. NSA existed as a printed product (Volumes 1-33) initially, created by DOE's predecessor, the U.S. Atomic Energy Commission (AEC). NSA includes citations to scientific and technical reports from the AEC, the U.S. Energy Research and Development Administration and its contractors, plus other agencies and international organizations, universities, and industrial and research organizations. References to books, conference proceedings, papers, patents, dissertations, engineering drawings, and journal articles from worldwide sources are also included. Abstracts and full text are provided if available.

Explaining Lithium Enriched Red Giant Branch Stars

Autore: Claudia Aguilera-Gómez
Editore: Springer
ISBN: 3030025837
Grandezza: 39,76 MB
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Vista: 2210
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This thesis provides new insights into the seemingly anomalous ubiquity of lithium-rich red giant stars. The theory of stellar evolution, one of the most successful models of modern astrophysics, predicts that red giant stars should display negligible levels of lithium (Li) on their surfaces. However, Li-rich giants, defined as those showing more than three times the Li content of the Sun, are found everywhere astronomers look in apparent defiance of established theory. The author addresses this problem, analyzing the different possible explanations for such an anomaly, which include interaction with a binary companion, the production of Li in the interior of the star with its subsequent transport to stellar exteriors, and the stellar interaction with planets. The author focuses on this last possibility, where the Li enrichment may be due to the ingestion of planets or brown dwarfs as the stars in question grew in size while becoming giants. She shows that this process is indeed able to explain an important fraction of giants with Li levels above the three times solar threshold, but that some other mechanism is needed to explain the remaining fraction. While this is an important discovery in its own right, the result that makes this thesis groundbreaking is its demonstration that the threshold between Li-normal and Li-rich is mass dependent rather than a fixed proportion of the Sun’s content. This corrects a fundamental misapprehension of the phenomenon and opens up a new framework in which to understand and solve the problem. Finally, the author presents interesting observational applications and samples with which to test this new approach to the problem of Li enrichment in giants.

The Stars

Autore: Evry L. Schatzman
Editore: Springer Science & Business Media
ISBN: 9783540541967
Grandezza: 21,95 MB
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Vista: 2389
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Following an introductory chapter on stellar fundamentals, the story begins of the lives and deaths of the stars. The authors take us on a journey from the sun, a comparatively young star, to supernovae - manifestations of dramatic death. On the way, the reader, advanced undergraduate or beginning postgraduate, is presented with such topics as stellar evolution, the hydrodynamics of stellar interiors, variability, and solar and stellar activity. This comprehensive but rigorous text, building on the theoretical and observational advances of recent years - for instance, astrophysical theory in the light of Supernova 1987A - is required reading for all serious students of astronomy.

Sirius Matters

Autore: Noah Brosch
Editore: Springer Science & Business Media
ISBN: 140208319X
Grandezza: 74,76 MB
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Vista: 8999
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Since very early times Sirius was a point of attraction in the night sky. It served to synchronize calendars in antiquity and was the subject of many myths and legends, including some modern ones. It was perceived as a red star for more than 400 years, but such reports were relegated to the Mediterranean region. Astronomically, Sirius is a very bright star. This, and its present close distance to us, argues in favor of it being the target of detailed studies of stellar structure and evolution. Its binary nature, with a companion that is one of the more massive white dwarfs, is an additional reason for such studies. This book collects the published information on Sirius in an attempt to derive a coherent picture of how this system came to look as it does.

Chemical Abundances In The Universe

Autore: International Astronomical Union. Symposium
Editore: Cambridge University Press
ISBN: 9780521764957
Grandezza: 38,23 MB
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Session I : Primordial nucleosynthesis and the first stars in the Universe -- Session II : First stars in the Galaxy -- Session III : Chemical abundances in the high red-shift Universe -- Session IV : Chemical abundance constraints on mass assembly and star formation in local galaxies and the Milky Way -- Session V : Extrasolar planets: the chemical abundance connection -- Session VI : Abundance surveys and projects in the era of future large telescopes.

Stellar Populations

Autore: Piet C. van der Kruit
Editore: Springer Science & Business Media
ISBN: 9780792335375
Grandezza: 16,13 MB
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Vista: 4935
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The concept of Stellar Populations has played a fundamental role in astronomy in the last few decades. It was introduced by Walter Baade after he was able to resolve the Andromeda Nebula and its companions into stars when he used red-sensitive plates and realised that there were two fundamentally different Herzsprung-Russell diagrams in our and these nearby galaxies (common stars in the solar neighborhood versus globular clusters). This result was published in two papers in 1944 in volume 100 of the Astrophysical Journal. Subsequent research gave the concept a much firmer basis and at the famous Vatican Symposium of 1957 resulted in a general scheme of the concept and a working hypothesis for idea's on the formation and evolution of the Galaxy. This has been a guiding principle of studies of our and other galaxies for decades. Some years ago it seemed to us appropriate to commemorate Baade's seminal work in 1994, when it would have its 50-th anniversary, and to review its present status and also its role in contempory understanding. While we were in Leiden for an administrative committee, we discussed the matter again and over beers on October 29, 1991 we decided the take the initiative for an IAU Symposium on the subject during the 1994 IAU General Assembly in Den Haag, the Netherlands.

Star Clusters

Autore: B.W. Carney
Editore: Springer Science & Business Media
ISBN: 3540676465
Grandezza: 25,79 MB
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Vista: 6983
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Star clusters are at the heart of astronomy, being key objects for our understanding of stellar evolution and galactic structure. Observations with the Hubble Space Telescope and other modern equipment have revealed fascinating new facts about these galactic building blocks. This book provides two comprehensive and up-to-date, pedagogically designed reviews on star clusters by two well-known experts in the field. Bruce Carney presents our current knowledge of the relative and absolute ages of globular clusters and the chemical history of our Galaxy. Bill Harris addresses globular clusters in external galaxies and their use as tracers of galaxy formation and cosmic distance indicators. The book is written for graduate students as well as professionals in astronomy and astrophysics.

The Chemical Evolution Of The Galaxy

Autore: Francesca Matteucci
Editore: Springer Science & Business Media
ISBN: 9781402016523
Grandezza: 51,73 MB
Formato: PDF
Vista: 7044
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This volume provides a thorough discussion of the evolution of elemental abundances in the Galaxy taking into account both spatial and temporal variations. For the first time, and in much greater detail, the observed chemical abundances are interpreted in terms of formation and evolution of the Galaxy. Observational constraints like the gas and star formation rate distribution are guiding this interpretation. Readers will find this monograph to be a unique research tool for expert scientists, graduate students, and everyone else who wants to get a deeper understanding of the chemical evolution of the Milky Way and galaxies in general.

The Impact Of Very High S N Spectroscopy On Stellar Physics

Autore: International Astronomical Union. Symposium
Editore: Springer Science & Business Media
ISBN: 9789027726957
Grandezza: 43,82 MB
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Vista: 1623
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Proceedings of the 132nd Symposium of the International Astronomical Union, held in Paris, France, June 29-July 3, 1987

The Realm Of Interacting Binary Stars

Autore: Jorge Sahade
Editore: Springer Science & Business Media
ISBN:
Grandezza: 63,40 MB
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Vista: 8804
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More than two centuries have elapsed since the story of interacting binary stars began with the rediscovery of the variability of Algol by John Goodricke and the interpretation he proposed for explaining the regular periodic brightness variations which he found.

Laboratory Astrochemistry

Autore: Stephan Schlemmer
Editore: John Wiley & Sons
ISBN: 3527653155
Grandezza: 45,28 MB
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Vista: 5059
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Written by leading scientists in the field and intended for a broader readership, this is an ideal starting point for an overview of current research and developments. As such, the book covers a broad spectrum of laboratory astrophysics and chemistry, describing recent advances in experiments, as well as theoretical work, including fundamental physics and modeling chemical networks. For researchers as well as students and newcomers to the field.

New Perspectives On Stellar Pulsation And Pulsating Variable Stars

Autore: International Astronomical Union. Colloquium
Editore: Cambridge University Press
ISBN: 9780521443821
Grandezza: 75,26 MB
Formato: PDF
Vista: 5147
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How can the interior of the Sun, white dwarfs and other stars be studied by stellar seismology? What can Doppler imaging tell us about high-degree pulsations? What impact are CCD and infrared observations having on extending the Cepheid and RR Lyrae distance scale? And how are other classes of pulsators providing independent checks of the distance scale? These and many other critical questions are answered in this timely review of the dramatic advances made in pulsating star research in the last decade. This survey collects together more than thirty comprehensive reviews and over one hundred summaries of research papers from the 139th IAU Colloquium, held in Victoria, British Columbia. Together these cover all aspects of recent developments in the field of variable star research and preview some of the exciting advances anticipated for the next decade. This volume provides an essential review for graduate students and researchers.

The A Star Puzzle Iau S224

Autore: International Astronomical Union. Symposium
Editore: Cambridge University Press
ISBN: 9780521850186
Grandezza: 53,65 MB
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Vista: 9065
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Explores some of the less well understood physical processes involved in the modeling of stars.

Astrophysical Concepts

Autore: Martin Harwit
Editore: Springer Science & Business Media
ISBN: 9780387949437
Grandezza: 38,61 MB
Formato: PDF
Vista: 6670
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This classic text - aimed at senior undergraduates and beginning graduate students in physics and astronomy - presents a wide range of concepts in sufficient depth to give the reader a quantitative understanding of the subject. Emphasising physical concepts, it provides the student with a series of astrophysical sketches, concluding with a synthesis of all the subjects discussed in the book, sketching the history of the universe from its beginning to the formation of the Sun and the planets.

Cosmic Magnetic Fields

Autore: Richard Wielebinski
Editore: Springer Science & Business Media
ISBN: 9783540241751
Grandezza: 52,82 MB
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Vista: 2763
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While magnetic fields permeate the universe on all scales, the present book is dedicated to their investigation on the largest scales and affords a balanced account of both theoretical and observational aspects. Written as a set of advanced lectures and tutorial reviews that lead up to the forefront of research, this book offers both a modern source of reference for the experienced researchers as well as a high-level introductory text for postgraduate students and nonspecialist researchers working in related areas.