Download or read book A Study of Large scale Structure Evolution Through Sunyaev Zel dovich Corrections in Massive Clusters written by Victoria Butler and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The evolution of large-scale structure is traced by galaxy clusters, which are groups of galaxies gravitationally bound by a shared envelope of dark matter on scales of 1-10 Mpc. They are filled with an intra-cluster medium (ICM) consisting of a diffuse hot plasma with characteristic temperature $107K. While ICM models match reasonably well with observations, smaller-scale astrophysical processes in clusters can complicate interpretations of derived thermodynamic properties. These can include cluster-cluster mergers, feedback from active black holes, and accretion, among several others. The complex relationship between these processes and the properties of the ICM must be understood to use clusters as a proxy for structure formation over cosmic history. My work uses two different instruments to constrain large-scale structure evolution and cluster astrophysics through observations of the diffuse ICM. The first is Herschel-SPIRE, which I used to measure cluster temperatures with the relativistic Sunyaev-Zel'dovich effect. The second is the Tomographic Ionized-carbon Mapping Experiment, which will perform observations of cluster peculiar velocities using the kinetic Sunyaev-Zel'dovich effect. These measurements will provide insight into the connection between clusters and the cosmic web of structure that influences their growth. This thesis will describe the creation and testing of an analysis pipeline to derive cluster ICM temperatures using archival SPIRE data, as well as the hardware and software development I performed for the TIME project, and my contributions during our two instrument deployments."--Abstract.
Download or read book Evolution of Clusters and Large scale Structures of Galaxies written by Chervin Laporte and published by . This book was released on 2014 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Evolution of the Large Scale Structure of the Universe Since Z written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In this thesis, the evolution of galaxy clustering from a redshift of $zsim1$ to the present epoch is investigated. The data used for this analysis were $sim4000$ galaxies in four fields of the Calar Alto Deep Imaging Survey (CADIS). The galaxies have luminosities brighter than $Ileq23^{mag}$, and redshifts with an error of $sigma_z=0.017$. The amplitude of the three-dimensional correlation function is estimated by deprojecting two-dimensional correlation functions. The reliability of the deprojection methods of the angular and projected correlation function is tested on the Las Campanas Redshift Survey (LCRS). Both angular and projected correlation function are calculated for different redshift bins, as local measurement the LCRS data is used. To facilitate the direct comparison of the two surveys, the influence of the redshift errors on the projected correlation function have to be taken into account. For evolution of the clustering strength the ansatz $xi(r_{com}, z)propto(1+z)^q$ is used. For the galaxies as a whole the evolution parameter turns out to be $qapprox-1.9$, according to the prediction of linear theory. A formal dependency on the cosmology is presumably due to the small number of fields observed. However, the measured clustering growth clearly depends on Hubble type. At $zsim1$ early type galaxies are already much stronger clustered, an increase with $qsimeq-1$ is sufficient to explain the present day amplitude of the correlation function.
Download or read book Probes of the Early Universe written by Max Tegmark and published by . This book was released on 1994 with total page 402 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Structure and Environment of Galaxy Clusters in Simulations and Observations written by Matthew Fong and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Galaxy clusters are powerful testing grounds for cosmology. They are the largest, most massively bound objects in the Universe and can give us deep insights on how baryons, dark matter, and dark energy impacts on the formation of large scale structure in the cosmos. In this dissertation we study the structure and environment of clusters, how neutrinos impact on cluster masses, and how we may find them. We study cluster profiles on large scales to gain better understanding on the relationship between cosmic web filaments and clusters that reside in the nodes, which gives insight on the evolution of clusters from their environment. For more than two decades, the Navarro, Frenk, and White (NFW) model has stood the test of time; it is used to describe the distribution of mass in galaxy clusters out to their outskirts, beyond which the NFW model is no longer applicable. In this dissertation we assess how well the parameterised Diemer & Kravstov (DK) mass density profile describes the mass distribution of galaxy clusters extracted from cosmological simulations. This is determined from averaged synthetic lensing measurements of the 50 most massive clusters extracted from the OverWhelmingly Large Simulations (Cosmo-OWLS). The characteristics of the data reflect the Weighing the Giants survey and data from the future Large Synoptic Survey Telescope (LSST). In comparison with the NFW model, the DK model is favored by the averaged data, in particular for the LSST data, where the number density of background galaxies is higher. The DK profile depends on the accretion history of clusters which is specified in the current study. Eventually subsamples of galaxy clusters with qualities indicative of disparate accretion histories could be studied. We also study the impact of baryonic processes and massive neutrinos on weak lensing (WL) peak statistics that can be used to constrain cosmological parameters. We use the BAHAMAS suite of cosmological simulations, which self-consistently include baryonic processes and the e↵ect of massive neutrino free-streaming on the evolution of structure formation. We construct synthetic WL catalogues by ray-tracing through light-cones, and use the aperture mass statistic for the analysis. The WL peaks reflect the cumulative signal from massive bound objects and general large-scale structure. We present the first study of WL peaks in simulations that include both baryonic physics and massive neutrinos, so that the uncertainty due to physics beyond the gravity of dark matter can be factored into constraints on cosmological models. Assuming a fiducial model of baryonic physics, we also investigate the correlation between peaks and massive haloes, over a range of neutrino masses. As higher neutrino mass tends to suppress the formation of massive structures in the Universe, the halo mass function and lensing peak counts are therefore modified as a function of neutrino mass. Over most of the S/N .5, the impact of fiducial baryonic physics is greater (less) than neutrinos for 0.06 and 0.12 (0.24 and 0.48) eV models. Both baryonic physics and massive neutrinos should be accounted for when deriving cosmological parameters from weak lensing observations.
Download or read book The Dark Universe written by Mario Livio and published by Cambridge University Press. This book was released on 2004-02-26 with total page 207 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume presents especially written articles by a host of world experts working on all aspects of dark matter and theories of gravity. This is an indispensable collection of review articles for researchers and graduate students.
Download or read book Galaxy Formation and Evolution written by Houjun Mo and published by Cambridge University Press. This book was released on 2010-05-20 with total page 841 pages. Available in PDF, EPUB and Kindle. Book excerpt: A coherent introduction for researchers in astronomy, particle physics, and cosmology on the formation and evolution of galaxies.
Download or read book Fundamental Properties of Galaxy Clusters written by Yen-Ting Lin and published by . This book was released on 2005 with total page 454 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Study of the Large scale Structure of the Universe with Galaxy Clusters written by Van Tuan Bui and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Large Scale Structure in lambda CDM Cosmology written by Joshua Daniel Younger and published by . This book was released on 2004 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 The Discovery of Cosmic Voids written by Laird A. Thompson and published by Cambridge University Press. This book was released on 2020-12-10 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: The large-scale structure of the Universe is dominated by vast voids with galaxies clustered in knots, sheets, and filaments, forming a great 'cosmic web'. In this personal account of the major astronomical developments leading to this discovery, we learn from Laird A. Thompson, a key protagonist, how the first 3D maps of galaxies were created. Using non-mathematical language, he introduces the standard model of cosmology before explaining how and why ideas about cosmic voids evolved, referencing the original maps, reproduced here. His account tells of the competing teams of observers, racing to publish their results, the theorists trying to build or update their models to explain them, and the subsequent large-scale survey efforts that continue to the present day. This is a well-documented account of the birth of a major pillar of modern cosmology, and a useful case study of the trials surrounding how this scientific discovery became accepted.
Download or read book The Large scale Structure of the Universe Environmental Effects and Relativistic Corrections written by Mikolaj Ryszard Borzyszkowski and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Precision Cosmology with Galaxy Cluster Surveys written by Hao-Yi Wu and published by Stanford University. This book was released on 2011 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt: The acceleration of the universe, which is often attributed to "dark energy, " has posed one of the main challenges to fundamental physics. Galaxy clusters provide one of the most sensitive probes of dark energy because their abundance reflects the growth rate of large-scale structure and the expansion rate of the universe. Several large galaxy cluster surveys will soon provide tremendous statistical power to constrain the properties of dark energy; however, the constraining power of these surveys will be determined by how well systematic errors are controlled. Of these systematic errors, the dominant one comes from inferring cluster masses using observable signals of clusters, the so-called "observable--mass distribution." This thesis focuses on extracting dark energy information from forthcoming large galaxy cluster surveys, including how we maximize the cosmological information, how we control important systematics, and how precisely we need to calibrate theoretical models. We study how multi-wavelength follow-up observations can improve cluster mass calibration in optical surveys. We also investigate the impact of theoretical uncertainties in calibrating the spatial distributions of galaxy clusters on dark energy constraints. In addition, we explore how the formation history of galaxy clusters impacts the self-calibration of cluster mass. In addition, we use N-body simulations to develop a new statistical sample of cluster-size halos in order to further understand the observable--mass distribution. We study the completeness of subhalos in our cluster sample by comparing them with the satellite galaxies in the Sloan Digital Sky Survey. We also study how subhalo selections impact the inferred correlation between formation time and optical mass tracers, including cluster richness and velocity dispersion.
Download or read book Large Scale Structure of the Universe written by and published by . This book was released on 1987 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book New Worlds New Horizons in Astronomy and Astrophysics written by National Research Council and published by National Academies Press. This book was released on 2011-02-04 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt: Driven by discoveries, and enabled by leaps in technology and imagination, our understanding of the universe has changed dramatically during the course of the last few decades. The fields of astronomy and astrophysics are making new connections to physics, chemistry, biology, and computer science. Based on a broad and comprehensive survey of scientific opportunities, infrastructure, and organization in a national and international context, New Worlds, New Horizons in Astronomy and Astrophysics outlines a plan for ground- and space- based astronomy and astrophysics for the decade of the 2010's. Realizing these scientific opportunities is contingent upon maintaining and strengthening the foundations of the research enterprise including technological development, theory, computation and data handling, laboratory experiments, and human resources. New Worlds, New Horizons in Astronomy and Astrophysics proposes enhancing innovative but moderate-cost programs in space and on the ground that will enable the community to respond rapidly and flexibly to new scientific discoveries. The book recommends beginning construction on survey telescopes in space and on the ground to investigate the nature of dark energy, as well as the next generation of large ground-based giant optical telescopes and a new class of space-based gravitational observatory to observe the merging of distant black holes and precisely test theories of gravity. New Worlds, New Horizons in Astronomy and Astrophysics recommends a balanced and executable program that will support research surrounding the most profound questions about the cosmos. The discoveries ahead will facilitate the search for habitable planets, shed light on dark energy and dark matter, and aid our understanding of the history of the universe and how the earliest stars and galaxies formed. The book is a useful resource for agencies supporting the field of astronomy and astrophysics, the Congressional committees with jurisdiction over those agencies, the scientific community, and the public.
Download or read book The First Galaxies in the Universe written by Abraham Loeb and published by Princeton University Press. This book was released on 2013-01-15 with total page 572 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a comprehensive, self-contained introduction to one of the most exciting frontiers in astrophysics today: the quest to understand how the oldest and most distant galaxies in our universe first formed. Until now, most research on this question has been theoretical, but the next few years will bring about a new generation of large telescopes that promise to supply a flood of data about the infant universe during its first billion years after the big bang. This book bridges the gap between theory and observation. It is an invaluable reference for students and researchers on early galaxies. The First Galaxies in the Universe starts from basic physical principles before moving on to more advanced material. Topics include the gravitational growth of structure, the intergalactic medium, the formation and evolution of the first stars and black holes, feedback and galaxy evolution, reionization, 21-cm cosmology, and more. Provides a comprehensive introduction to this exciting frontier in astrophysics Begins from first principles Covers advanced topics such as the first stars and 21-cm cosmology Prepares students for research using the next generation of large telescopes Discusses many open questions to be explored in the coming decade
