Download or read book The Masses and Dynamics of Galaxy Clusters written by Lyndsay J. Old and published by . This book was released on 2015 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fundamentals of Galaxy Dynamics Formation and Evolution written by Ignacio Ferreras and published by UCL Press. This book was released on 2019-04-02 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: Galaxies, along with their underlying dark matter halos, constitute the building blocks of structure in the Universe. Of all fundamental forces, gravity is the dominant one that drives the evolution of structures from small density seeds at early times to the galaxies we see today. The interactions among myriads of stars, or dark matter particles, in a gravitating structure produce a system with fascinating connotations to thermodynamics, with some analogies and some fundamental differences. Ignacio Ferreras presents a concise introduction to extragalactic astrophysics, with emphasis on stellar dynamics, and the growth of density fluctuations in an expanding Universe. Additional chapters are devoted to smaller systems (stellar clusters) and larger ones (galaxy clusters). Fundamentals of Galaxy Dynamics, Formation and Evolution is written for advanced undergraduates and beginning postgraduate students, providing a useful tool to get up to speed in a starting research career. Some of the derivations for the most important results are presented in detail to enable students appreciate the beauty of maths as a tool to understand the workings of galaxies. Each chapter includes a set of problems to help the student advance with the material.
Download or read book Outskirts of Galaxy Clusters IAU C195 written by International Astronomical Union. Colloquium and published by Cambridge University Press. This book was released on 2004-12-16 with total page 586 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains the proceedings of the International Astronomical Union Colloquium no. 195, held in Torino, Italy in 2004. The meeting investigated the formation of galaxies within a full cosmological context, focusing on the outer regions of galaxy clusters. The observed correlation of optical and radio properties of galaxies with their environment indicates that the formation and evolution of galaxies is intimately linked to the formation of large scale structure. With chapters written by leading authorities in the field, this timely volume investigates the role of the environment in determining the properties of galaxies. It describes the distribution of matter and galaxies on the largest scales in the Universe, the processes of cluster and galaxy formation, their role and interplay. This is a valuable collection of review articles for professional astronomers.
Download or read book Internal Dynamics of Galaxy Clusters in the Red Sequence Cluster Survey written by Kris Blindert and published by . This book was released on 2006 with total page 250 pages. Available in PDF, EPUB and Kindle. Book excerpt: We compute the global dynamical properties of the clusters in our survey, such as velocity dispersion and mass, and use them to explore the properties of RCS clusters as functions of total cluster mass. In particular, we first examine the optical richness as an inexpensive proxy for mass. The calibration of this relation is an important ingredient in the construction of the cluster mass function, which is used to constrain cosmological parameters. Our relation and scatter are consistent with self-calibrated cosmological parameter results. We also study the cluster mass-to-light ratios, and how they scale with mass. We compare our results to other observations and to structure formation models. Although the scatter in this relation is large, we find agreement among remarkably different types of galaxy clusters and groups; however, current structure formation models do not accurately reproduce the variation of M/L with mass. We present a spectroscopic survey of clusters of galaxies, designed to explore the distribution of matter, and its relation to light, in these massive systems. Our sample is drawn from the Red-sequence Cluster Survey (RCS), and is composed of 33 clusters with a wide range of optical richness and a moderate range of redshift. We obtained spectra of 56 to 529 objects per cluster, which yielded over 3500 redshifts of which 1014 are cluster members. To account for survey incompleteness due to sparse sampling, we constructed several empirical corrections so that our redshift catalogue is suitable for use in dynamical analysis. To boost statistics and allow us to perform a more detailed dynamical analysis of clusters, we stack our data into "ensemble" clusters. Cosmological simulations predict a roughly universal density profile for dark matter haloes over many scales, and a relation between halo mass and the concentration of the profile. We analyse the ensembles using the jeans equations, and recover density profiles for several ensemble clusters of different masses. Although the sampling of our data at small radii is insufficient to constrain some quantities of interest such as the inner core slope of the density profile, we can constrain the concentrations and orbital anisotropies for the ensemble clusters. We find they agree with predictions and previous observations: namely, that galaxies in clusters follow roughly isotropic orbits, and the concentrations of cluster density profiles are consistent with the prediction one would obtain from their masses. We also estimate the variation of concentration with redshift, finding a slightly stronger evolution than expected.
Download or read book A Pan Chromatic View of Clusters of Galaxies and the Large Scale Structure written by Manolis Plionis and published by Springer. This book was released on 2008-02-17 with total page 476 pages. Available in PDF, EPUB and Kindle. Book excerpt: The reviews presented in this volume cover a huge range of cluster of galaxies topics. Readers will find the book essential reading on subjects such as the physics of the ICM gas, the internal cluster dynamics, and the detection of clusters using different observational techniques. The expert chapter authors also cover the huge advances being made in analytical or numerical modeling of clusters, weak and strong lensing effects, and the large scale structure as traced by clusters.
Download or read book Clusters of Galaxies written by Bethlee M. Lindor and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The mass-function of galaxy clusters in the Universe reveals information about the formation, evolution, and processes behind celestial objects. Previous attempts to probe masses of clusters have depended on various methods, including kinematics and dynamics, X-ray observations, and gravitational lensing. When studies use X-ray observations to derive cluster masses, they assume that the gas within the cluster is in hydrostatic equilibrium (HSE). The problem with this assumption is that clusters are not necessarily in HSE. As such, HSE mass measurements are often compared with more reliable lensing masses in order to reveal the systematic bias of the HSE assumption. In this work, we investigate the uncertainties in the bias of mass determination for a sample of 25 galaxy clusters using precision cosmology. This will enable the use of clusters -- the most massive virialized systems in the universe -- as accurate tools in determining cosmological parameters including the dark-matter and dark-energy density of the universe. In this work, we measure a mean mass bias of $0.9 +- 0.09 -- consistent with the current literature.
Download or read book Globular Clusters Guides to Galaxies written by Tom Richtler and published by Springer Science & Business Media. This book was released on 2008-11-23 with total page 448 pages. Available in PDF, EPUB and Kindle. Book excerpt: The principal question of whether and how globular clusters can contribute to a better understanding of galaxy formation and evolution is perhaps the main driving force behind the overall endeavour of studying globular cluster systems. Naturally, this splits up into many individual problems. The objective of the Joint ESO-FONDAP Workshop on Globular Clusters - Guides to Galaxies was to bring together researchers, both observational and theoretical, to present and discuss the most recent results. Topics covered in these proceedings are: internal dynamics of globular clusters and interaction with host galaxies (tidal tails, evolution of cluster masses), accretion of globular clusters, detailed descriptions of nearby cluster systems, ultracompact dwarfs, formations of massive clusters in mergers and elsewhere, the ACS Virgo survey, galaxy formation and globular clusters, dynamics and kinematics of globular cluster systems and dark matter-related problems. With its wide coverage of the topic, this book constitutes a valuable reference of the scientific knowledge of the field.
Download or read book Galactic Dynamics written by James Binney and published by Princeton University Press. This book was released on 2011-10-30 with total page 902 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since it was first published in 1987, Galactic Dynamics has become the most widely used advanced textbook on the structure and dynamics of galaxies and one of the most cited references in astrophysics. Now, in this extensively revised and updated edition, James Binney and Scott Tremaine describe the dramatic recent advances in this subject, making Galactic Dynamics the most authoritative introduction to galactic astrophysics available to advanced undergraduate students, graduate students, and researchers. Every part of the book has been thoroughly overhauled, and many sections have been completely rewritten. Many new topics are covered, including N-body simulation methods, black holes in stellar systems, linear stability and response theory, and galaxy formation in the cosmological context. Binney and Tremaine, two of the world's leading astrophysicists, use the tools of theoretical physics to describe how galaxies and other stellar systems work, succinctly and lucidly explaining theoretical principles and their applications to observational phenomena. They provide readers with an understanding of stellar dynamics at the level needed to reach the frontiers of the subject. This new edition of the classic text is the definitive introduction to the field. ? A complete revision and update of one of the most cited references in astrophysics Provides a comprehensive description of the dynamical structure and evolution of galaxies and other stellar systems Serves as both a graduate textbook and a resource for researchers Includes 20 color illustrations, 205 figures, and more than 200 problems Covers the gravitational N-body problem, hierarchical galaxy formation, galaxy mergers, dark matter, spiral structure, numerical simulations, orbits and chaos, equilibrium and stability of stellar systems, evolution of binary stars and star clusters, and much more Companion volume to Galactic Astronomy, the definitive book on the phenomenology of galaxies and star clusters
Download or read book Merging Processes in Galaxy Clusters written by L. Feretti and published by Springer Science & Business Media. This book was released on 2006-04-18 with total page 329 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mergers are the mechanisms by which galaxy clusters are assembled through the hierarchical growth of smaller clusters and groups. Major cluster mergers are the most energetic events in the Universe since the Big Bang. Many of the observed properties of clusters depend on the physics of the merging process. These include substructure, shock, intra cluster plasma temperature and entropy structure, mixing of heavy elements within the intra cluster medium, acceleration of high-energy particles, formation of radio halos and the effects on the galaxy radio emission. This book reviews our current understanding of cluster merging from an observational and theoretical perspective, and is appropriate for both graduate students and researchers in the field.
Download or read book Mass Distribution in Galaxy Clusters written by Mauricio Carrasco and published by . This book was released on 2014 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dynamics and Evolution of Galactic Nuclei written by David Merritt and published by Princeton University Press. This book was released on 2013-07-21 with total page 567 pages. Available in PDF, EPUB and Kindle. Book excerpt: Deep within galaxies like the Milky Way, astronomers have found a fascinating legacy of Einstein's general theory of relativity: supermassive black holes. Connected to the evolution of the galaxies that contain these black holes, galactic nuclei are the sites of uniquely energetic events, including quasars, stellar tidal disruptions, and the generation of gravitational waves. This textbook is the first comprehensive introduction to dynamical processes occurring in the vicinity of supermassive black holes in their galactic environment. Filling a critical gap, it is an authoritative resource for astrophysics and physics graduate students, and researchers focusing on galactic nuclei, the astrophysics of massive black holes, galactic dynamics, and gravitational wave detection. It is an ideal text for an advanced graduate-level course on galactic nuclei and as supplementary reading in graduate-level courses on high-energy astrophysics and galactic dynamics. David Merritt summarizes the theoretical work of the last three decades on the evolution of galactic nuclei, the formation of massive black holes, and the interaction between black holes and stars. He explores in depth such important topics as observations of galactic nuclei, dynamical models, weighing black holes, motion near supermassive black holes, evolution of nuclei due to gravitational encounters, loss cone theory, and binary supermassive black holes. Self-contained and up-to-date, the textbook includes a summary of the current literature and previously unpublished work by the author. For researchers working on active galactic nuclei, galaxy evolution, and the generation of gravitational waves, this book will be an essential resource.
Download or read book Dynamics of Young Star Clusters and Associations written by Cathie Clarke and published by Springer. This book was released on 2015-09-11 with total page 356 pages. Available in PDF, EPUB and Kindle. Book excerpt: Where do most stars (and the planetary systems that surround them) in the Milky Way form? What determines whether a young star cluster remains bound (such as an open or globular cluster), or disperses to join the field stars in the disc of the Galaxy? These questions not only impact understanding of the origins of stars and planetary systems like our own (and the potential for life to emerge that they represent), but also galaxy formation and evolution, and ultimately the story of star formation over cosmic time in the Universe. This volume will help readers understand our current views concerning the answers to these questions as well as frame new questions that will be answered by the European Space Agency's Gaia satellite that was launched in late 2013. The book contains the elaborated notes of lectures given at the 42nd Saas-Fee Advanced Course “Dynamics of Young Star Clusters & Associations" by Cathie Clarke (University of Cambridge) who presents the theory of star formation and dynamical evolution of stellar systems, Robert Mathieu (University of Wisconsin) who discusses the kinematics of star clusters and associations, and I. Neill Reid (S pace Telescope Science Institute) who provides an overview of the stellar populations in the Milky Way and speculates on from whence came the Sun. As part of the Saas-Fee Advanced Course Series, the book offers an in-depth introduction to the field serving as a starting point for Ph.D. research and as a reference work for professional astrophysicists.
Download or read book Clusters of Galaxies written by Florence Durret and published by Atlantica Séguier Frontières. This book was released on 1994 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mass Distribution in Galaxy Clusters written by Mauricio Efraín Carrasco Venegas and published by . This book was released on 2014 with total page 182 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Mass and Dynamics of CD Clusters with Cooling Flows 1 written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2019-01-04 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: As a part of a program to determine the mass distribution of cD galaxy clusters with cooling flows, we obtained a ROSAT image of the cluster A 496. The image reveals sharply peaked emission centered on the cD galaxy. Both the peaked cooling flow emission and the more extended emission filling the cluster are centered on the cD galaxy to within 15 sec. The surface brightness profile is consistent with previous Einstein HRI observations. We measure spatially resolved spectra for the x-ray emission, and find a significant decline in temperature in the innermost 2 to 4 min. We also find a gradient in absorption due to cold neutral gas, with excess absorption, however, is far below previously reported values. We caution that this is a progress report, and that our results are preliminary. Kriss, Gerard A. NASA-CR-191240, NAS 1.26:191240 NAG5-1636...
Download or read book X Ray Emission from Clusters of Galaxies written by Craig L. Sarazin and published by Cambridge University Press. This book was released on 1988-03-17 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: First published in 1988, this book is a comprehensive survey of the astrophysical characteristics of the hot gas which pervades clusters of galaxies. In our universe, clusters of galaxies are the largest organised structures. Typically they comprise hundreds of galaxies moving through a region of space ten million light years in diameter. The volume between the galaxies is filled with gas having a temperature of 100 million degrees. This material is a strong source of cosmic X-rays. Dr Sarazin describes the theoretical description of the origin, dynamics, and physical state of the cluster gas. Observations by radio and optical telescopes are also summarised. This account is addressed to professional astronomers and to graduate students. It is an exhaustive summary of a rapidly expanding field of research in modern astrophysics.
Download or read book The Dark Matter Problem in Rotationally Supported Galaxies written by Pengfei Li and published by . This book was released on 2020 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt: Different lines of evidence suggest that the observed dynamics of galaxies, galaxy clusters, and the Universe as a whole cannot be explained by the visible, baryonic matter when applying the standard laws of Gravity. Two competing solutions have been proposed and hotly debated in the past decades: introduce dark matter (DM) or modify the laws of gravity. In this dissertation, I present a systematic investigation of these two hypothesis using 175 late-type galaxies from the Spitzer Photometry \& Accurate Rotation Curves (SPARC) database. On the DM front, I fit the SPARC rotation curves testing seven different halo profiles. Based on these fits, I explore the correlations between DM halos and stellar disks, and find that the characteristic volume density of DM halos is remarkably constant over 5 decades in galaxy luminosity. This serves as a testing bed for galaxy formation models. Using the correlation between DM halo masses and \hi\ line widths, I measure for the first time the DM halo mass function (HMF). The measured HMF agrees with the prediction of DM-only simulations at intermediate and low halo masses, but differs significantly at high mass end. Finally I compute the effect of adiabatic compression on the DM halos due to the baryonic gravitational potential, and find that compressed halos contribute more to rotation curves, exacerbating the core-cusp problem over the whole range of galaxy masses. On the modified gravity front, I test the statistically established radial acceleration relation (RAR) which indicates a strong link between the baryonic mass distribution and the observed dynamics of galaxies. The vast majority of the SPARC galaxies can be well described by the RAR. The best-fit RAR has an rms scatter of 0.057 dex, comparable to the observational uncertainties on rotation curves. This leaves little room for intrinsic scatter if any. I check the critical acceleration scale in the RAR is universal among late-type galaxies, marking no difference between the RAR and the Modified Newtonian Dynamics. Overall, Modified Newtonian Dynamics can describe disk galaxies with less problems than DM models, but a comprehensive evaluation requires the systematic investigations on galaxy-cluster and cosmological scales.
