Download or read book Understanding the Nature of Stellar Chemical Abundance Distributions in Nearby Stellar Systems written by Duane Morris Lee and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Since stars retain signatures of their galactic origins in their chemical compositions, we can exploit the chemical abundance distributions that we observe in stellar systems to put constraints on the nature of their progenitors. In this thesis, I present results from three projects aimed at understanding how high resolution spectroscopic observations of nearby stellar systems might be interpreted. The first project presents one possible explanation for the origin of peculiar abundance distributions observed in ultra-faint dwarf satellites of the Milky Way. The second project explores to what extent the distribution of chemical elements in the stellar halo can be used to trace Galactic accretion history from the birth of the Galaxy to the present day. Finally, a third project focuses on developing an input optimization algorithm for the second project to produce better estimates of halo accretion histories. In conclusion, I propose some other new ways to use statistical models and techniques along with chemical abundance distribution data to uncover galactic histories.
Download or read book Not So Simple Stellar Populations in Star Clusters written by Chengyuan Li and published by Springer. This book was released on 2017-09-19 with total page 137 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book focuses on understanding the stellar populations of massive star clusters and aims to investigate the origin, evolution and properties of binary systems, their collision products, as well as the general characteristics (e.g. ages, metal content) of stellar population(s) in star clusters. It introduces the basic background knowledge of various stellar populations in star clusters as well as their formation, interaction and evolution and offers high impact observational results on our understanding of the formation and evolution mode of star clusters. Based on these discoveries, this book proposes a series of future projects that can shed light on these topics. The research introduced in this book reveals key features of star clusters formation and by extension how all stars formed in our universe.
Download or read book Planets Stars and Stellar Systems written by Gerard Gilmore and published by Springer. This book was released on 2013-02-23 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is volume 5 of Planets, Stars and Stellar Systems, a six-volume compendium of modern astronomical research, covering subjects of key interest to the main fields of contemporary astronomy. This volume on “Galactic Structure and Stellar Populations”, edited by Gerard F. Gilmore, presents accessible review chapters on Stellar Populations, Chemical Abundances as Population Tracers, Metal-Poor Stars and the Chemical Enrichment of the Universe, The Stellar and Sub-Stellar Initial Mass Function of Simple and Composite Populations, The Galactic Nucleus, The Galactic Bulge, Open Clusters and Their Role in the Galaxy, Star Counts and the Nature of Galactic Thick Disk, The Infrared Galaxy, Interstellar PAHs and Dust, Galactic Neutral Hydrogen, High-Velocity Clouds, Magnetic Fields in Galaxies, Astrophysics of Galactic Charged Cosmic Rays, Gamma-Ray Emission of Supernova Remnants and the Origin of Galactic Cosmic Rays, Galactic Distance Scales, Globular Cluster Dynamical Evolution, Dynamics of Disks and Warps, Mass Distribution and Rotation Curve in the Galaxy, Dark Matter in the Galactic Dwarf Spheroidal Satellites, and History of Dark Matter in Galaxies. All chapters of the handbook were written by practicing professionals. They include sufficient background material and references to the current literature to allow readers to learn enough about a specialty within astronomy, astrophysics and cosmology to get started on their own practical research projects. In the spirit of the series Stars and Stellar Systems published by Chicago University Press in the 1960s and 1970s, each chapter of Planets, Stars and Stellar Systems can stand on its own as a fundamental review of its respective sub-discipline, and each volume can be used as a textbook or recommended reference work for advanced undergraduate or postgraduate courses. Advanced students and professional astronomers in their roles as both lecturers and researchers will welcome Planets, Stars and Stellar Systems as a comprehensive and pedagogical reference work on astronomy, astrophysics and cosmology.
Download or read book Chemical Evolution of Nearby Stellar Systems written by Andrea Kayser and published by . This book was released on 2007 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Chemical Evolution of Galaxies written by Francesca Matteucci and published by Springer Science & Business Media. This book was released on 2012-01-05 with total page 237 pages. Available in PDF, EPUB and Kindle. Book excerpt: The term “chemical evolution of galaxies” refers to the evolution of abundances of chemical species in galaxies, which is due to nuclear processes occurring in stars and to gas flows into and out of galaxies. This book deals with the chemical evolution of galaxies of all morphological types (ellipticals, spirals and irregulars) and stresses the importance of the star formation histories in determining the properties of stellar populations in different galaxies. The topic is approached in a didactical and logical manner via galaxy evolution models which are compared with observational results obtained in the last two decades: The reader is given an introduction to the concept of chemical abundances and learns about the main stellar populations in our Galaxy as well as about the classification of galaxy types and their main observables. In the core of the book, the construction and solution of chemical evolution models are discussed in detail, followed by descriptions and interpretations of observations of the chemical evolution of the Milky Way, spheroidal galaxies, irregular galaxies and of cosmic chemical evolution. The aim of this book is to provide an introduction to students as well as to amend our present ideas in research; the book also summarizes the efforts made by authors in the past several years in order to further future research in the field.
Download or read book Chemical Abundances in the Universe written by International Astronomical Union. Symposium and published by Cambridge University Press. This book was released on 2010 with total page 518 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Stellar Structure written by Stanley Bashkin and published by . This book was released on 1965 with total page 696 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Planetary Mineralogy written by M.R. Lee and published by The Mineralogical Society of Great Britain and Ireland. This book was released on 2015-04-20 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume of the EMU Notes in Mineralogy is one of the outcomes of a school in planetary mineralogy that was held in Glasgow, Scotland, in 2014. The school was inspired by the recent advances in our understanding of the nature and evolution of our Solar System that have come from the missions to study and sample asteroids and comets, and the very successful Mars orbiters and landers. At the same time our horizons have expanded greatly with the discovery of extrasolar protoplanetary disks, planets and planetary systems by space telescopes. The continued success of such telescopic and robotic exploration requires a supply of highly skilled people and so one of the goals of the Glasgow school was to help build a community of early-career planetary scientists and space engineers.
Download or read book Stellar Abundances in the Solar Neighborhood written by Natalie R. Hinkel and published by . This book was released on 2012 with total page 193 pages. Available in PDF, EPUB and Kindle. Book excerpt: The only elements that were made in significant quantity during the Big Bang were hydrogen and helium, and to a lesser extent lithium. Depending on the initial mass of a star, it may eject some or all of the unique, newly formed elements into the interstellar medium. The enriched gas later collapses into new stars, which are able to form heavier elements due to the presence of the new elements. When we observe the abundances in a stellar regions, we are able to glean the astrophysical phenomena that occurred prior to its formation. I compile spectroscopic abundance data from 49 literature sources for 46 elements across 2836 stars in the solar neighborhood, within 150 pc of the Sun, to produce the Hypatia Catalog. I analyze the variability of the spread in abundance measurements reported for the same star by different surveys, the corresponding stellar atmosphere parameters adopted by various abundance determination methods, and the effect of normalizing all abundances to the same solar scale. The resulting abundance ratios [X/Fe] as a function of [Fe/H] are consistent with stellar nucleosynthetic processes and known Galactic thin-disk trends. I analyze the element abundances for 204 known exoplanet host-stars. In general, I find that exoplanet host-stars are not enriched more than the surrounding population of stars, with the exception of iron. I examine the stellar abundances with respect to both stellar and planetary physical properties, such as orbital period, eccentricity, planetary mass, stellar mass, and stellar color. My data confirms that exoplanet hosts are enriched in [Fe/H] but not in the refractory elements, per the self-enrichment theory for stellar composition. Lastly, I apply the Hypatia Catalog to the Catalog of Potentially Habitable Stellar Systems in order to investigate the abundances in the 1224 overlapping stars. By looking at stars similar to the Sun with respect to six bio-essential elements, I created maps that have located two ``habitability windows'' on the sky: (20.6hr, -4.8deg) and (22.6hr, -48.5deg). These windows may be of use in future targeted or beamed searches.
Download or read book Stellar Atmospheres written by Cecilia Helena Payne Gaposchkin and published by . This book was released on 1925 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt: Original thesis submitted to Radcliffe College. The typescript is a summary of the thesis with handwritten ink insertions. The galley proof contains the full text and bears blue and graphite pencil markings. A library thesis use form is affixed to the bottom of the first page of the galley.
Download or read book Chemodynamical Properties of Simulated Late type Galaxies written by Kate Pilkington 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 Abundance Effect on Extragalactic Stellar Systems written by R. J. Terlevich and published by . This book was released on 1982 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Abundance Effects on Extragalactic Stellar Systems written by Roberto Juan Terlevich and published by . This book was released on 1982 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Accuracy of Element Abundances from Stellar Atmospheres written by Rainer Wehrse and published by Springer. This book was released on 2014-08-23 with total page 109 pages. Available in PDF, EPUB and Kindle. Book excerpt: To get a reasonably realistic picture of the structure and evolution of stars one needs to know accurately the abundances of chemical elements and their isotopes in the stellar atmosphere and in the galactic environment of the stars. The articles collected in this volume give a modern review of the abundance accuracies for main-sequence stars. After a general introduction in the first part the accuracies of atomic transition probabilities, ionization and excitation cross-sections, and line broad- ening data are discussed. In the second part the specific problems and results for different stellar types are presented, and, finally, an overview on the possibilities of abundance determinations for stars outside the Galaxy is given.
Download or read book Origins of the Earth Moon and Life written by Akio Makishima and published by Elsevier. This book was released on 2017-01-27 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt: Origins of the Earth, Moon, and Life: An Interdisciplinary Approach presents state-of-the-art knowledge that is based on theories, experiments, observations, calculations, and analytical data from five astro-sciences, astronomy, astrobiology, astrogeology, astrophysics, and cosmochemistry. Beginning with the origin of elements, and moving on to cover the formation of the early Solar System, the giant impact model of the Earth and Moon, the oldest records of life, and the possibility of life on other planets in the Solar System, this interdisciplinary reference provides a complex understanding of the planets and the formation of life. Synthesizing concepts from all branches of astro-sciences into one, the book is a valuable reference for researchers in astrogeology, astrophysics, cosmochemistry, astrobiology, astronomy, and other space science fields, helping users better understand the intersection of these sciences. Includes extensive figures and tables to enhance key concepts Uses callout boxes throughout to provide context and deeper explanations Presents up-to-date information on the universe, stars, planets, moons, and life in the solar system Combines knowledge from the fields of astrogeology, astrophysics, cosmochemistry, astrobiology, and astronomy, helping readers understand the origins of the Earth, the moon, and life in our solar system
Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1976 with total page 612 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mass Distribution of Hot Stellar Systems written by Xiaoan Wu and published by . This book was released on 2007 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: The mass distribution of hot stellar systems is hard to measure because they do not contain gas or star disks, and because there is a degeneracy between the overall mass distribution and the distribution function of the observable particles. Assuming that the potential is spherical, we describe a maximum-likelihood nonparametric method to utilize to the full extent available kinematic data, which is applied to an elliptical galaxy (M87), three dwarf spheroidal galaxies (Draco, Ursa Minor and Fornax) and a globular cluster (o Centauri). For M87, the mass within 32 kpc is (2:4 +/- 0:6) x 1012 M ⊙ , and the exponent of the density profile rho ∝ r -alpha in the range 10 - 100 kpc is alpha = 1:6 +/- 0:4. The energy distribution suggests a few kinematically distinct groups of globular clusters. For dwarf spheroidal galaxies, our models naturally produce the so-called "extra-tidal extensions", which had previously been suggested as evidence of tidal stripping. The average V-band mass-to-light ratio is 400 +/- 80M ⊙ =LV, ⊙ within 0:75 kpc for Draco, 580+140-100 M ⊙ =V, ⊙ within 1:1 kpc for Ursa Minor and 25+7-5 M ⊙ =LV, ⊙ within 2:5 kpc for Fornax. We do not find that anisotropy contributes substantially to the high mass-to-light ratios in these dSph galaxies. For o Centauri, we derive an averaged (V -band) mass-to-light ratio Gamma = 2:96 +/- 0:10 M ⊙ /L ⊙ . Moreover, we find no evidence that the even part of the DF is dependent on total angular momentum; that is, two-integral models in which the DF depends on energy and the z'-component of angular momentum are sufficient to fit the data.
