Download or read book Stellar Collisions Mergers an sic Their Consequences written by Michael M. Shara and published by . This book was released on 2002 with total page 480 pages. Available in PDF, EPUB and Kindle. Book excerpt: Annotation Thirty-one papers from the June 2000 New York conference discuss the following: hydrodynamics in stellar collisions and mergers; massive stars; collisions and merger products as star cluster populations; stellar collisions, pulsar planets, and helium white dwarf mergers; gigantic nuclei; general relativity, gravitational radiation, and gamma ray bursts; and, n-body simulations. There is no index. Annotation (c)2003 Book News, Inc., Portland, OR (booknews.com)
Download or read book Stellar Collisions Mergers An d Their Consequences written by Michael M. Shara and published by . This book was released on 2002 with total page 426 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Evolution of Stellar Velocity Dispersion in Galaxy Mergers written by Nathaniel Roland Stickley and published by . This book was released on 2013 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: I find that velocity dispersion increases rapidly and significantly as two galaxies pass through one another. As galaxies recede from a collision, their velocity dispersions rapidly decrease and nearly return to their pre-collision values. Velocity dispersion increases in all directions during collisions, however the enhancement is most significant along the collision axis. After the nuclei of the progenitor system coalesce, the velocity dispersion oscillates slightly of the coalesced system oscillated around its final equilibrium value for up to several dynamical timescales.
Download or read book Star Formation in Merging Clusters of Galaxies written by Alison Seiler Mansheim and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis straddles two areas of cosmology, each of which are active, rich and plagued by controversy in their own right: merging clusters and the environmental dependence of galaxy evolution. While the greater context of this thesis is major cluster mergers, our individual subjects are galaxies, and we apply techniques traditionally used to study the differential evolution of galaxies with environment. Our first system (Chapter 2) is a cluster merger known as Musket Ball that is in a post-merging state. Our second system (Chapter 3), referred to as Cl J0910, is comprised of two clusters that have not yet merged. The order in which they are presented is intentional because, while it would have made more sense to study the pre-merger system first, our approach in Chapter 3 was shaped by what we learned by handling the significantly more difficult post-merger system. The body of this thesis is drawn from two papers: Mansheim et al. 2016a and Mansheim et al. 2016b, one on each system. Both projects benefited from exquisite data sets assembled as part of the Merging Cluster Collaboration (MC2), and Observations of Redshift Evolution in Large Scale Environments (ORELSE) survey, allowing us to scrutinize the evolutionary states of galaxy populations in multiple lights. Multi-band optical and near-infrared imaging was available for both systems, allowing us to calculate photometric redshifts for completeness corrections, colors (red vs. blue) and stellar masses to view the ensemble properties of the populations in and around each merger. High-resolution spectroscopy was also available for both systems, allowing us to confirm cluster members by measuring spectroscopic redshifts, which are unparalleled in accuracy, and gauge star formation rates and histories by measuring the strengths of certain spectral features. We had the luxury of HST imaging for Musket Ball, allowing us to use galaxy morphology (late-type vs. early-type) as an additional diagnostic. For Cl J0910, 24 [mu]m imaging allowed us to defeat a most pernicious source of uncertainty (dusty starburst vs. quiescent). Details on the acquisition and reduction of multi-wavelength data for each system are found within each respective chapter. It is important to note that the research presented in Chapter 3 is based on a letter which had significant space restrictions, so much of the observational details are outsourced to papers written by ORELSE collaboration members. Below is a free-standing summary of each project, drawn from the abstracts of each paper. The Chapter 1 contains an introduction to the topic and motivation to fill a vacuum in knowledge using our hypothesis. Chapter 4, following the meat of the thesis in Chapters 2 and 3, gives closure and looks to the future. In Chapter 2, we investigate star formation in DLSCL J0916.2+2953, a dissociative merger of two clusters at z=0.53 that has progressed 1.1[superscript +1.3][subscript-0.4] Gyr since first pass-through. We attempt to reveal the effects a collision may have had on the evolution of the cluster galaxies by tracing their star formation history. We probe current and recent activity to identify a possible star formation event at the time of the merger using EW(H[delta]), EW[(OII)], and D[subscript n](4000) measured from the composite spectra of 64 cluster and 153 coeval field galaxies. We supplement Keck DEIMOS spectra with DLS and HST imaging to determine the color, stellar mass, and morphology of each galaxy and conduct a comprehensive study of the populations in this complex structure. Spectral results indicate the average cluster and cluster red sequence galaxies experienced no enhanced star formation relative to the surrounding field during the merger, ruling out a predominantly merger-quenched population. We find that the average blue galaxy in the North cluster is currently active and in the South cluster is currently post-starburst having undergone a recent star formation event. While the North activity could be latent or long-term merger effects, a young blue stellar population and irregular geometry suggest the cluster was still forming prior the collision. While the South activity coincides with the time of the merger, the blue early-type population could be a result of secular cluster processes. The evidence suggests that the dearth or surfeit of activity is indiscernible from normal cluster galaxy evolution. In Chapter 3, we examine the effects of an impending cluster merger on galaxies in the large scale structure (LSS) RX Cl J0910 at z =1.105. Using multi-wavelength data, including 102 spectral members drawn from the ORELSE survey and precise photometric redshifts, we calculate extinction-corrected star formation rates and map the specific star formation rate density of the LSS galaxies. These analyses along with an investigation of the color-magnitude properties of LSS galaxies indicate lower levels of star formation activity in the region between the merging clusters relative to the outskirts of the system. We suggest gravitational tidal forces due to the potential of merging halos may be the physical mechanisms responsible for the observed suppression of star formation in galaxies caught between the merging clusters.
Download or read book The Energy of Stellar Collision written by Alexander William Bickerton and published by . This book was released on 1904 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Simulations of Binary Galaxy Mergers written by Damien Chapon and published by . This book was released on 2011 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Galaxy interactions and mergers are key events in the history of our Universe. Each one of them impacts the fragile equilibrium state of the galaxies, their morphology, their mass and star formation rate in a drastic way. Small scale physical processes play a major role during galaxy mergers: their complex interplay leads to high level of complexity and is far from being completely understood. In past numerical studies, the lack of resolution and of a consistent thermodynamical model for a multi-phase turbulent interstellar medium was one of the main caveat of galactic scale simulations. The aim of this thesis if to study the effect of galaxy collision and mergers on the small scale physical processes by using high-resolution numerical simulations. The AMR hydrodynamical code RAMSES used in this work is described in chapter 3, as well as the additional modules developed for the specific purpose of galaxy merger simulations. In chapter 4,1 will present a high-resolution Antennae galaxy (NGC4038/39) merger simulation. In this numerical study, the use of a "pseudo-cooling" thermodynamical model leaded to a merger-induced clustered starburst, in fair agreement with thé star formation properties in observed galaxies. Chapter 5 will focus on the formation of a super-massive black hole binary at the center of a nuclear disk resulting from an equal-mass galaxy merger simulation. The effect of dynamical friction by a gaseous medium on the SMBHs pairing process is properly resolved down to sub-parsec scales. Finally, a new data processing and visualization module called PyMSES co-developed specifically for the RAMSES data structure is introduced in chapter 6.
Download or read book The Cambridge N Body Lectures written by Sverre Aarseth and published by Springer. This book was released on 2008-09-02 with total page 405 pages. Available in PDF, EPUB and Kindle. Book excerpt: Published under the auspices of the Royal Astronomical Society, this volume contains a set of extensive school tested lectures, with the aim to give a coherent and thorough background knowledge of the subject and to introduce the latest developments in N-body computational astrophysics. The topics cover a wide range from the classical few-body problem with discussions of resonance, chaos and stability to realistic modelling of star clusters as well as descriptions of codes, algorithms and special hardware for N-body simulations. This collection of topics, related to the gravitational N-body problem, will prove useful to both students and researchers in years to come. 1) Published under the auspices of the Royal Astronomical Society.
Download or read book Ecology of Blue Straggler Stars written by Henri M. J. Boffin and published by Springer. This book was released on 2014-12-03 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt: The existence of blue straggler stars, which appear younger, hotter, and more massive than their siblings, is at odds with a simple picture of stellar evolution. Such stars should have exhausted their nuclear fuel and evolved long ago to become cooling white dwarfs. They are found to exist in globular clusters, open clusters, dwarf spheroidal galaxies of the Local Group, OB associations and as field stars. This book summarises the many advances in observational and theoretical work dedicated to blue straggler stars. Carefully edited extended contributions by well-known experts in the field cover all the relevant aspects of blue straggler stars research: Observations of blue straggler stars in their various environments; Binary stars and formation channels; Dynamics of globular clusters; Interpretation of observational data and comparison with models. The book also offers an introductory chapter on stellar evolution written by the editors of the book.
Download or read book International Aerospace Abstracts written by and published by . This book was released on 1998 with total page 614 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Unveiling Galaxies written by Jean-René Roy and published by Cambridge University Press. This book was released on 2018 with total page 311 pages. Available in PDF, EPUB and Kindle. Book excerpt: A thought provoking study of the powerful impact of images in guiding astronomers' understanding of galaxies through time.
Download or read book Energy Research Abstracts written by and published by . This book was released on 1988 with total page 1472 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Financial Crisis Inquiry Report written by Financial Crisis Inquiry Commission and published by Cosimo, Inc.. This book was released on 2011-05-01 with total page 692 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Financial Crisis Inquiry Report, published by the U.S. Government and the Financial Crisis Inquiry Commission in early 2011, is the official government report on the United States financial collapse and the review of major financial institutions that bankrupted and failed, or would have without help from the government. The commission and the report were implemented after Congress passed an act in 2009 to review and prevent fraudulent activity. The report details, among other things, the periods before, during, and after the crisis, what led up to it, and analyses of subprime mortgage lending, credit expansion and banking policies, the collapse of companies like Fannie Mae and Freddie Mac, and the federal bailouts of Lehman and AIG. It also discusses the aftermath of the fallout and our current state. This report should be of interest to anyone concerned about the financial situation in the U.S. and around the world.THE FINANCIAL CRISIS INQUIRY COMMISSION is an independent, bi-partisan, government-appointed panel of 10 people that was created to "examine the causes, domestic and global, of the current financial and economic crisis in the United States." It was established as part of the Fraud Enforcement and Recovery Act of 2009. The commission consisted of private citizens with expertise in economics and finance, banking, housing, market regulation, and consumer protection. They examined and reported on "the collapse of major financial institutions that failed or would have failed if not for exceptional assistance from the government."News Dissector DANNY SCHECHTER is a journalist, blogger and filmmaker. He has been reporting on economic crises since the 1980's when he was with ABC News. His film In Debt We Trust warned of the economic meltdown in 2006. He has since written three books on the subject including Plunder: Investigating Our Economic Calamity (Cosimo Books, 2008), and The Crime Of Our Time: Why Wall Street Is Not Too Big to Jail (Disinfo Books, 2011), a companion to his latest film Plunder The Crime Of Our Time. He can be reached online at www.newsdissector.com.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1992 with total page 1572 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Evolution of The Milky Way written by F. Matteucci and published by Springer Science & Business Media. This book was released on 2000 with total page 644 pages. Available in PDF, EPUB and Kindle. Book excerpt: This review of the most up-to-date observational and theoretical information concerning the chemical evolution of the Milky Way compares the abundances derived from field stars and clusters, giving information on the abundances and dynamics of gas.
Download or read book The Astronomers Magic Envelope written by Prasenjit Saha and published by Oxford University Press. This book was released on 2018 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: Working physicists, and especially astrophysicists, value a good `back-of-the-envelope' calculation, meaning a short, elegant computation or argument that starts from general principles and leads to an interesting result. This book guides students on how to understand astrophysics using general principles and concise calculations -- endeavouring to be elegant where possible and using short computer programs where necessary. The material proceeds in approximate historical order. The book begins with the Enlightenment-era insight that the orbits of the planets is easy, but the orbit of the Moon is a real headache, and continues to deterministic chaos. This is followed by a chapter on spacetime and black holes. Four chapters reveal how microphysics, especially quantum mechanics, allow us to understand how stars work. The last two chapters are about cosmology, bringing us to 21st-century developments on the microwave background and gravitational waves.
Download or read book The Big Bang Never Happened written by Eric Lerner and published by Vintage. This book was released on 1992-10-27 with total page 497 pages. Available in PDF, EPUB and Kindle. Book excerpt: A mesmerizing challenge to orthodox cosmology with powerful implications not only for cosmology itself but also for our notions of time, God, and human nature -- with a new Preface addressing the latest developments in the field. Far-ranging and provocative, The Big Bang Never Happened is more than a critique of one of the primary theories of astronomy -- that the universe appeared out of nothingness in a single cataclysmic explosion ten to twenty billion years ago. Drawing on new discoveries in particle physics and thermodynamics as well as on readings in history and philosophy, Eric J. Lerner confronts the values behind the Big Bang theory: the belief that mathematical formulae are superior to empirical observation; that the universe is finite and decaying; and that it could only come into being through some outside force. With inspiring boldness and scientific rigor, he offers a brilliantly orchestrated argument that generates explosive intellectual debate.
Download or read book The 71F Advantage written by National Defense University Press and published by NDU Press. This book was released on 2010-09 with total page 529 pages. Available in PDF, EPUB and Kindle. Book excerpt: Includes a foreword by Major General David A. Rubenstein. From the editor: "71F, or "71 Foxtrot," is the AOC (area of concentration) code assigned by the U.S. Army to the specialty of Research Psychology. Qualifying as an Army research psychologist requires, first of all, a Ph.D. from a research (not clinical) intensive graduate psychology program. Due to their advanced education, research psychologists receive a direct commission as Army officers in the Medical Service Corps at the rank of captain. In terms of numbers, the 71F AOC is a small one, with only 25 to 30 officers serving in any given year. However, the 71F impact is much bigger than this small cadre suggests. Army research psychologists apply their extensive training and expertise in the science of psychology and social behavior toward understanding, preserving, and enhancing the health, well being, morale, and performance of Soldiers and military families. As is clear throughout the pages of this book, they do this in many ways and in many areas, but always with a scientific approach. This is the 71F advantage: applying the science of psychology to understand the human dimension, and developing programs, policies, and products to benefit the person in military operations. This book grew out of the April 2008 biennial conference of U.S. Army Research Psychologists, held in Bethesda, Maryland. This meeting was to be my last as Consultant to the Surgeon General for Research Psychology, and I thought it would be a good idea to publish proceedings, which had not been done before. As Consultant, I'd often wished for such a document to help explain to people what it is that Army Research Psychologists "do for a living." In addition to our core group of 71Fs, at the Bethesda 2008 meeting we had several brand-new members, and a number of distinguished retirees, the "grey-beards" of the 71F clan. Together with longtime 71F colleagues Ross Pastel and Mark Vaitkus, I also saw an unusual opportunity to capture some of the history of the Army Research Psychology specialty while providing a representative sample of current 71F research and activities. It seemed to us especially important to do this at a time when the operational demands on the Army and the total force were reaching unprecedented levels, with no sign of easing, and with the Army in turn relying more heavily on research psychology to inform its programs for protecting the health, well being, and performance of Soldiers and their families."
