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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.

Red giants. --- Lithium. --- Alkali metals --- Red giant stars --- Giant stars --- Astrophysics. --- Mathematical physics. --- Astrophysics and Astroparticles. --- Theoretical Astrophysics. --- Physical mathematics --- Physics --- Astronomical physics --- Astronomy --- Cosmic physics --- Mathematics

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Based on a Simons Symposium held in 2018, the proceedings in this volume focus on the theoretical, numerical, and observational quest for dark matter in the universe. Present ground-based and satellite searches have so far severely constrained the long-proposed theoretical models for dark matter. Nevertheless, there is continuously growing astrophysical and cosmological evidence for its existence. To address present and future developments in the field, novel ideas, theories, and approaches are called for. The symposium gathered together a new generation of experts pursuing innovative, more complex theories of dark matter than previously considered.This is being done hand in hand with experts in numerical astrophysical simulations and observational techniques—all paramount for deciphering the nature of dark matter. The proceedings volume provides coverage of the most advanced stage of understanding dark matter in various new frameworks. The collection will be useful for graduate students, postdocs, and investigators interested in cutting-edge research on one of the biggest mysteries of our universe.

Dark matter (Astronomy) --- Astrophysics. --- Mathematical physics. --- Observations, Astronomical. --- Astronomy—Observations. --- Astrophysics and Astroparticles. --- Theoretical Astrophysics. --- Astronomy, Observations and Techniques. --- Astronomical observations --- Observations, Astronomical --- Physical mathematics --- Physics --- Astronomical physics --- Astronomy --- Cosmic physics --- Mathematics

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This didactic book uses a data-driven approach to connect measurements made by plasma instruments to the real world. This approach makes full use of the instruments’ capability and examines the data at the most detailed level an experiment can provide. Students using this approach will learn what instruments can measure, and working with real-world data will pave their way to models consistent with these observations. While conceived as a teaching tool, the book contains a considerable amount of new information. It emphasizes recent results, such as particle measurements made from the Cluster ion experiment, explores the consequences of new discoveries, and evaluates new trends or techniques in the field. At the same time, the author ensures that the physical concepts used to interpret the data are general and widely applicable. The topics included help readers understand basic problems fundamental to space plasma physics. Some are appearing for the first time in a space physics textbook. Others present different perspectives and interpretations of old problems and models that were previously considered incontestable. This book is essential reading for graduate students in space plasma physics, and a useful reference for the broader astrophysics community. .

Physics. --- Fluids. --- Astrophysics. --- Plasma (Ionized gases). --- Astrophysics and Astroparticles. --- Plasma Physics. --- Solar and Heliospheric Physics. --- Theoretical Astrophysics. --- Fluid- and Aerodynamics. --- Gaseous discharge --- Gaseous plasma --- Magnetoplasma --- Ionized gases --- Astronomical physics --- Astronomy --- Cosmic physics --- Physics --- Hydraulics --- Mechanics --- Hydrostatics --- Permeability --- Natural philosophy --- Philosophy, Natural --- Physical sciences --- Dynamics --- Solar system. --- Mathematical physics. --- Solar and Heliospheric Physics . --- Physical mathematics --- Mathematics --- Space plasmas. --- Solar wind.

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Magnetism in binary stars is an area of central importance in stellar astrophysics. The second edition of "Magnetohydrodynamics in Binary Stars" is a major revision of the first edition. The material has been updated and extended, including additional chapters on the origins of the stellar magnetic fields and accretion disc magnetic winds. A comprehensive account is given of the subject, from the early work up to the latest results. The unifying theme remains the redistribution of angular momentum by magnetic stresses. This occurs in a wide variety of ways, including magnetic stellar and orbital coupling, magnetic channelling of accretion streams, magnetic stellar coupling to accretion discs, dynamo field coupling in discs, and magnetic stellar and disc winds. The associated stellar spin and orbital evolution problems, including stability, are also considered. Although the main focus is on binary stars, much of the work on accretion discs and wind flows has more general astrophysical relevance. Convenient formulae are included that can be compared to observations, making the book useful to observers as well as theorists, and there are extensive reference lists. The material is mainly aimed at research workers, but parts of the text could be useful for postgraduate courses in magnetic stellar astrophysics topics.

Double stars. --- Magnetohydrodynamics. --- Magneto-hydrodynamics --- MHD (Physics) --- Fluid dynamics --- Plasma dynamics --- Binaries (Stars) --- Binary stars --- Stars, Double --- Multiple stars --- Astrophysics. --- Mathematical physics. --- Astrophysics and Astroparticles. --- Theoretical Astrophysics. --- Plasma Physics. --- Physical mathematics --- Physics --- Astronomical physics --- Astronomy --- Cosmic physics --- Mathematics --- Plasma (Ionized gases). --- Gaseous discharge --- Gaseous plasma --- Magnetoplasma --- Ionized gases

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The book reviews theories of nucleosynthesis in big-bang cosmology. It introduces the standard model of cosmology, astronuclear reactions, numerical techniques for nucleosynethsis, and describes in detail the theories that go beyond the standard models, enabling readers to grasp the physics of big-bang nucleosynthesis on the basis of cosmology, general relativity and nuclear physics. In addition, the authors provide insights into the theoretical constrains required by observations. As a consequence, readers find out that big-bang nucleosynthesis still has windows opened to another cosmology. Although the book focuses on highly advanced topics, it is concisely written and mathematical derivations are explained step-by-step, making it accessible to graduate readers. Thus it is a short monograph appealing to a variety of readers interested in nucleosynthesis of big-bang cosmology.

Big bang theory. --- Nucleosynthesis. --- Nucleogenesis --- Chemical elements --- Cosmochemistry --- Big bang cosmology --- Superdense theory --- Cosmogony --- Cosmology --- Expanding universe --- Astrophysics. --- Mathematical physics. --- Nuclear physics. --- Cosmology. --- Theoretical Astrophysics. --- Nuclear Physics, Heavy Ions, Hadrons. --- Astrophysics and Astroparticles. --- Classical and Quantum Gravitation, Relativity Theory. --- Atomic nuclei --- Atoms, Nuclei of --- Nucleus of the atom --- Physics --- Physical mathematics --- Astronomical physics --- Astronomy --- Cosmic physics --- Mathematics