Download or read book The Growth of Massive Galaxies and Clusters at High Redshift written by Robert Raymond Lindner and published by . This book was released on 2013 with total page 231 pages. Available in PDF, EPUB and Kindle. Book excerpt: Massive galaxies and galaxy clusters gain much of their mass by merging with their neighbors; this hierarchical structure formation is the foundation of our understanding of galaxy evolution. Nevertheless, the detailed evolutionary processes needed to form the structures we see in the local Universe remain poorly understood. This thesis comprises four projects examining the growth of galaxies and clusters at high redshift by using radio, sub/millimeter, and X-ray observations to provide empirical constraints on their cosmic evolution. Chapter 2 presents deep 1.2mm imaging of the inner 20' x 20' of the Lockman Hole North (LHN) field to search for submillimeter galaxies (SMGs), rapidly star-forming, high-redshift galaxy mergers. We detect 41 SMGs with S/N>4.0 and use Monte Carlo simulations to estimate their number counts and angular clustering properties. Chapter 3 investigates the nuclear accretion properties of the LHN SMGs. In the sample's average rest-frame X-ray spectrum, we detect strong Fe K alpha emission (equivalent width EW>=1 keV) from highly-ionized Fe species -- evidence that beneath the galaxies' heavy obscuration, supermassive black holes may be growing rapidly. Chapter 4 describes a new 345 GHz and 2.1 GHz imaging campaign to study the intracluster media (ICM) of eleven massive Sunyaev Zel'dovich Effect (SZE)-detected clusters from the Atacama Cosmology Telescope (ACT) southern survey. In six of eleven, 345 GHz SZE increments are detected and used to characterize the spatial distribution and energy content of the ICM at high (19.2") resolution. This work helps us understand how SZE-mass scaling relations are affected by contamination from other sources along the line of sight and by dynamical properties of the ICM. Chapter 5 studies the non-thermal radio emission in one exceptional z=0.870 binary cluster merger (ACTJ0102-4915, ``El Gordo'') with the help of newly-acquired radio observations. El Gordo is the highest-redshift cluster known to host double radio ``relics'' and a radio ``halo, '' and by characterizing the morphology, intensity, spectral index, and polarization of these structures, we extend our knowledge of ICM shocks and magnetic fields to an era when the Universe was only 50% its current age.
Download or read book High Redshift Galaxies written by Immo Appenzeller and published by Springer Science & Business Media. This book was released on 2009-06-17 with total page 353 pages. Available in PDF, EPUB and Kindle. Book excerpt: The high-redshift galaxies became a distinct research ?eld during the ?nal decade of the20thcentury. AtthattimetheLyman-breaktechniquemadeitpossibletoidentify signi?cant samples of such objects, and the new generation of 8 to 10-m telescopes resulted in ?rst good spectroscopic data. Today the high-redshift galaxies have developed into one of the important topics of astrophysics, accounting for about 5–10% of the publications in the major scienti?c journals devoted to astronomy. Because high-redshift galaxies is a rapidly developing ?eld and since new results are published constantly, writing a book on this topic is challenging. On the other hand, in view of the large amount of individual results now in the literature, and in view of the still growing interest in this topic, it appears worthwhile to summarize and evaluate the available data and to provide an introduction for those who wish to enter this ?eld, or who, for various reasons, might be interested in its results. The end of the ?rst decade of the 21st century appears to be a good point in time to attempt such a summary. The current generation of ground-based 8 to 10-m - optical telescopes, the Hubble Space Telescope, and the most important large radio telescopes have by now been in operation since about one or two decades. Although these instruments will continue to produce important scienti?c results for some time to come, many of the initial programs exploiting their unique new possibilities have been completed.
Download or read book Galaxies at High Redshift written by I. Pérez-Fournon and published by Cambridge University Press. This book was released on 2003-03-20 with total page 302 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume presents lectures of the XI Canary Islands Winter School of Astrophysics written by experts in the field.
Download or read book Magnificent Constructions written by Kevin Christopher Cooke and published by . This book was released on 2019 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt: "To understand how the present day universe came to be, we must understand how the massive structures in which we live formed and evolved over the preceding billions of years. Constraining how galaxies grow are the most massive galaxies, called brightest cluster galaxies (BCGs). These luminous and diffuse elliptical galaxies inhabit relaxed positions within their host cluster's gravitational potentials and provide a look at the high mass extreme of galaxy evolution. The relaxed structure, old stellar populations, and central location within the cluster indicate a high redshift formation scenario, however, star-forming BCGs have been observed at much more recent epochs. Addressing this evolutionary complexity, my dissertation consists of four studies to investigate the growth rates of BCGs over several epochs, and how they relate to the growth of the general galaxy population. In my first paper, I present a multiwavelength (far-ultraviolet to far-infrared) study of BCG star formation rates and stellar masses from 0.2 z 0.7 (Cooke et al. 2016), selected from the CLASH and SGAS surveys. I find that in-situ star formation in my sample is consistent with overall quiescence, and star-forming BCGs remain very rare. In my second paper (Cooke et al. 2018), my sample's redshift range is expanded to z ~ 1 with the addition of massive BCGs (M_Stellar 10^11 M_Solar) from galaxy clusters available in the COSMOS X-ray Group Catalog. I find that star formation is roughly constant in our sample of high mass BCGs from 0.3
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 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 The Mass of Galaxies at Low and High Redshift written by Ralf Bender and published by Springer Science & Business Media. This book was released on 2003-01-23 with total page 394 pages. Available in PDF, EPUB and Kindle. Book excerpt: Measuring the masses of galaxies as a function of redshift is perhaps one of the most challenging open issues in current astronomical research. The evolution of the baryonic and dark matter components of galaxies is not only a critical test of the hierarchical formation paradigm, but ultimately also provides new clues on the complex interplay between star formation, the cooling and heating of gas and galaxy merging processes. This book reviews current techniques to measure the baryonic (stellar) and dark masses of nearby galaxies, and focusses on ongoing attempts to measure theses same quantities in galaxies at higher and higher redshifts. It also gives room to future perspectives, with special emphasis on new survey projects and satellite missions.
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 BRIGHT Lights BIG City written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: High redshift radio galaxies are great cosmological tools for pinpointing the most massive objects in the early Universe: massive forming galaxies, active super-massive black holes and proto-clusters. They report on deep narrow-band imaging and spectroscopic observations of several z> 2 radio galaxy fields to investigate the nature of giant Ly-[alpha] nebulae centered on the galaxies and to search for over-dense regions around them. They discuss the possible implications for our understanding of the formation and evolution of massive galaxies and galaxy clusters.
Download or read book Towards Understanding Galaxies at Large Redshift written by Richard G. Kron and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt: This workshop was intended as an update and an extension of the workshop 011 the "Spectral Evolution of Galaxies" that was held in Erice two years ago. It concentrates 011 Ilew developments concerning galaxies seen at large look back times. This seemed also a good opportunity to look ahead to the next generation of ground- and space based instrumentation, and to consider various future strategies for collecting information concerning the edge of the observable universe. The main idea was to bring together people with specialities in modelling galaxy components (such as stars, clusters, gas, and dust) as well as whole stellar systems (stellar populations, star formation rates, chemical enrichment), and people specialized in making direct measurements of galaxies and clusters at large look back times. The confrontation of expectations and observations was planned to be the central theme of the conference, which explains the title "Towards Understanding Galaxies at Large Redshift". The first part of the workshop focussed on the physical processes that operate in galaxies, and that would likely have some observable manifestation at large redshifts. In the second part the most recent observational work was reported, and we were pleased to have the participation of most of the groups active in this field. The last part was directed towards new approaches to be made possible by the next generation of instrumentation, although in general all the contributions were indeed in this spirit of setting more ambitious goals.
Download or read book From Dusty to Dust free written by Logan Houston Jones and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The creation of new stars from cold gas is one of the most fundamental astrophysical processes that can be observed in our own galaxy and in others. At a broad level, the modern phenomenological picture of how stars form is consistent with observations of systems ranging from nearby molecular clouds to the most distant galaxies. Many gaps and limitations in the details of such a picture, however, remain unfilled and unanswered. For example, questions remain about the interplay between star formation and chemical enrichment in blue, metal-poor galaxies and the impact of that relationship in cosmic reionization -- one of the final frontiers of observational extragalactic astrophysics. Meanwhile, on the other end of the electromagnetic and metallicity spectrum, there exists a population of high-redshift, far-infrared-bright, and heavily dust-obscured starbursting galaxies that represent a fleeting but possibly integral stage in the growth of massive galaxies and of dense, large-scale structures like (proto)clusters of galaxies. However, the mechanism(s) that trigger such starbursts, especially in dense environments, remains ambiguous. The research that comprises this dissertation aims to answer two questions that, while both relevant to astronomers' understanding of the birth and evolution of galaxies in the broadest sense, are largely disjoint from one another. These questions are: 1) What are the intermediate- to high-redshift analogs to the sources that reionized the universe at very early times?; and 2) As a function of redshift and/or environment, how common are massively star-forming, dust-obscured galaxies? Because these questions are so different from one another, this dissertation will be split into two major parts. In the first, I present a search in two legacy fields (the GOODS-North and the GOODS-South) for galaxies at high redshift that may be sources of ionizing ultraviolet photons. Such objects are expected to be analogs, in various ways, to the first generation of galaxies, and thus provide clues to the nature of very-high-redshift galaxies that will be discovered en masse by future ground- and space-based observatories. In the second part, I present the spectroscopic confirmation of an overdensity of dusty starbursting galaxies at $z \approx 3.14$, signposting a protocluster of galaxies near the peak of star formation activity in the universe. Compared to similar recent discoveries in the literature, this new protocluster is relatively late-forming and includes several of the most infrared-luminous starbursts currently known. This makes it an excellent laboratory for testing theories of starburst triggering and the subsequent buildup of stellar mass in dense environments. In the final chapter of this dissertation, I reiterate the key results of the research presented in chapters 2, 3, and 5.
Download or read book Galaxy Proto clusters as an Interface Between Structure Cluster and Galaxy Formation written by Yi-Kuan Chiang and published by . This book was released on 2016 with total page 358 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proto-clusters, the distant progenitor large-scale structures of present day galaxy clusters, represent a key phase of cluster growth during which most of the galaxies were still rapidly forming stars. They are potentially powerful cosmological probes, and are unique laboratories to study dark matter assembly, the cosmic baryon cycle, and the environmental impact on galaxy evolution. Albeit its pivotal role in understanding cluster formation, only a small and heterogeneous sample of proto-clusters has been observed to date. Theoretical characterizations have also remained relatively unexplored. In this dissertation, I present baseline models, detailed theory predictions, and broad observational applications of proto-clusters using state-of-the-art numerical simulations and deep-wide galaxy surveys. A dual focus of both structure formation and galaxy evolution is given throughout the thesis. To prepare for large statistical studies in upcoming surveys like the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX), the Subaru Prime Focus Spectrograph (PFS) survey, and the Wide Field Infrared Survey Telescope (WFIRST) survey, I develop key machinery to connect the main observables of proto-clusters with dark matter structure formation using simulations as a guide. In Chapter 2 and 3, I present, for the first time, a thorough analysis of the main properties of proto-clusters using ~3000 clusters in a set of cosmological N-body simulations and semi-analytic galaxy models. I characterize the growth of proto-clusters and their core halos in size and mass with cosmic time. I show that the progenitor regions of galaxy clusters can already be identified in galaxy surveys at very early times (at least up to z~5), provided that the galaxy overdensities are measured on a sufficiently large scale (5--30 Mpc comoving) and with sufficient statistics. I present the overdensities in matter, dark matter halos, and galaxies as functions of present-day cluster mass, redshift, bias, and selection window size that can be used to interpret the wide range of structures found in real surveys. A table of proto-cluster candidates selected from the literature is provided, and I discuss their properties in light of our simulation predictions. In Chapter 4 I report the discovery of a large sample of proto-cluster candidates in the 1.62 deg^2 COSMOS/UltraVISTA field traced by optical/infrared selected galaxies with photometric redshifts. By comparing properly smoothed three-dimensional galaxy density maps of the observations and a set of matched simulations incorporating the main observational effects, I found 36 candidate structures at 1.610^14} M_sun. With solely photometric redshifts, I successfully rediscover two spectroscopically confirmed structures in this field, suggesting that our algorithm is robust. This work is the first large sample of uniformly selected proto-cluster candidates, providing rich targets for spectroscopic follow-up and subsequent studies of cluster formation. Because of the need of precise galaxy redshifts for density mapping and the prevalence of star formation before quenching, nearly all the proto-clusters known to date were confirmed by spectroscopy of galaxies with strong emission lines. In Chapter 5 I develop a semi-empirical model for Lya escape and generate a set of mock Lya emitter catalogs. This formalism provides a realistic modeling of the galaxy bias, the scatter of the bias, and the stochasticity of the galaxy-dark matter halo connection, which has an enormous potential for studies of the large-scale structure at high redshift. The model suggests that there are two distinct regimes to power a Lya emitter. For massive galaxies, Lya emitters are preferentially less dusty and slightly less metal enriched, while their ages and star formation rates are indistinguishable from other star-forming galaxies of the same mass. In contrast, low mass Lya emitters M_star
Download or read book The Evolution of Red type Galaxies Near Massive High Redshift Clusters written by Jess Alan Wilhelm and published by . This book was released on 2008 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Clusters of Galaxies written by William R. Oegerle and published by Cambridge University Press. This book was released on 1990 with total page 415 pages. Available in PDF, EPUB and Kindle. Book excerpt: Collected in this volume are the review papers from the Space Telescope Science Institute symposium on Clusters of Galaxies held in May 1989. Fifteen experts in the field have presented summaries of our current understanding of the formation and evolution of clusters and their constituent galaxies. Subjects covered include the existence and importance of subclustering, models of the evolution of clusters and the intracluster medium, the effect of the cluster environment on galaxies, observations of high redshift clusters, and the use of clusters as tracers of large scale structure. This book provides a timely focus for future observational and theoretical work on clusters of galaxies.
Download or read book Black Hole Masses in Nearby Brightest Cluster Galaxies written by Nicholas James McConnell and published by . This book was released on 2012 with total page 356 pages. Available in PDF, EPUB and Kindle. Book excerpt: The most massive galaxies in the Universe live at the centers of galaxy clusters and exhibit a number of extreme properties. Although their evolution broadly resembles that of normal elliptical galaxies, with early gas quenching and gradual assembly from smaller stellar systems, their unique cosmic environments may have offered additional pathways for growth. The extreme stellar mass growth of BCGs is clearly demonstrated by their overall luminosities, but the growth histories and present-day masses of their central black holes are not well known. A key body of evidence for the evolutionary connections between galaxies and supermassive black holes is the set of scaling relations between black hole masses (MBH) and the stellar velocity dispersions ([sigma]), luminosities (L), or bulge masses (Mbulge) of their host galaxies. However, these scaling relations are poorly sampled for BCGs. Populating the relations with direct measurements of MBH could offer new insights to the growth of black holes and stellar systems at the hearts of galaxy clusters. Along with collaborators, I have undertaken a series of observations of the centers of BCGs, using integral-field spectrographs on the Keck, Gemini, and Harlan J. Smith telescopes. In this dissertation, I describe the measurement and analysis of stellar kinematics at the centers of five BCGs, and measurements of their black hole masses using stellar orbit models. The most notable result is the measurement of black holes with approximately 10 billion solar masses in NGC 3842 and NGC 4889. These are the largest black hole masses ever directly measured, and they significantly exceed predictions from both the MBH-[sigma] and MBH-L relations. Their masses are comparable to the biggest black holes powering high-redshift quasars, suggesting a tantalizing link between early sites of prolific black hole growth and rich galaxy clusters today. In contrast, I find that NGC 6086 and NGC 7768 host black holes with only a few billion solar masses. These measurements, as well as my upper limit for MBH in NGC 2832, are more consistent with the existing black hole scaling relations. Recent measurements by my team and others have reshaped the sample of well-measured black hole masses, introducing significant updates to previous compilations. I present a sample of 65 dynamical black hole mass measurements, compiled from published literature through May 2012. In addition to previously reported values of [sigma] and L, I have compiled an updated sample of bulge masses for 34 galaxies. The updated sample yields a steeper MBH-[sigma] relation than previous versions, while the MBH-L and MBH-Mbulge relations experience relatively small changes. I have examined the black hole scaling relations for a variety of galaxy subsamples and find noteworthy variations in the MBH-[sigma] relation for early- versus late-type galaxies and core-profile versus power-law galaxies. Using the new sample, I have measured the empirical scatter in MBH and have attempted to measure the intrinsic scatter for multiple intervals in [sigma], L, and Mbulge. This is an important step forward from previous studies, which have only measured the intrinsic scatter over the full range of a given host galaxy property. Several models of black hole growth over cosmic time have predicted decreasing scatter in MBH as galaxy mass increases, reflecting the influence of hierarchical mergers driving galaxies and black holes toward an average MBH/Mbulge ratio. In contrast, I find nearly constant scatter in MBH over a wide range of galaxy luminosities and bulge masses. My investigations thus far have contributed to a gradual change in astronomers' understanding of the black hole scaling relations. The present-day relations are not as tight as previously reported versions, and evidence is mounting against a universal process for co-evolution between black holes and galaxies. I will use observations of a larger sample of BCGs and massive group galaxies to explore the effects of environment on the growth of individual black holes and on cosmic scatter in MBH.
Download or read book High Redshift and Primeval Galaxies written by Jacqueline Bergeron and published by Atlantica Séguier Frontières. This book was released on 1987 with total page 548 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Brightest Cluster Galaxies written by Christopher John Bildfell and published by . This book was released on 2006 with total page 210 pages. Available in PDF, EPUB and Kindle. Book excerpt: Galaxies grow and evolve via the repeated process of hierarchical merging, with smaller galaxies being cannibalized by larger and correspondingly brighter ones. Thus in galaxy clusters it is the brightest cluster galaxy (BCG) that lies at the top of the galaxian food chain and deep within the cluster potential the BCG grows to become one of the most massive galaxies in the universe. Baryonic feedback processes associated with the formation of the BCG (eg., AGN, star formation, stellar winds and chemical enrichment) affect the balance between heating and cooling of the intra-cluster medium (ICM) which in turn, through replenishment of the cold gas reservoir of the BCG, feeds back on these processes. This interconnection between the BCG and the state of the cluster gas has direct implications for theories of both galaxy and cluster evolution. Thanks to recent advances in observational techniques it has become possible to study the link between BCG and host cluster properties across a wide range of multi-wavelength information. Using deep imaging data taken with the Canada-France-Hawaii Telescope as part of the Canadian Cluster Comparison Project. (CCCP). we examine the surface brightness distributions in g' and r' of 28 BCGs in a redshift range 0.15 z 0.55 residing in massive clusters with Tx> 5 and compare them to the global X-ray properties of their hosts. We fit R1/4 models to the surface brightness profiles and find that the Kormendy relation of BCGs, when corrected for passive evolution. is consistent with that of the local elliptical population. We identify a subset of BCGs with extraordinarily blue centers (0.1
