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Book A Novel Measurement of Sunyaev Zel dovich Effect in Galaxy Clusters

Download or read book A Novel Measurement of Sunyaev Zel dovich Effect in Galaxy Clusters written by Thor Miller Wilbanks and published by . This book was released on 1994 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book High Resolution Measurements of the Sunyaev Zel dovich Effect in Galaxy Clusters at 90 GHz

Download or read book High Resolution Measurements of the Sunyaev Zel dovich Effect in Galaxy Clusters at 90 GHz written by Alexander H. Young and published by . This book was released on 2014 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt: The MUltiplexed SQUID/TES Array at Ninety GHz (MUSTANG) is a 64-pixel array of transition-edge sensor (TES) bolometers built at the University of Pennsylvania (UPenn) for the Green Bank Telescope (GBT) in collaboration with a number of universities and government agencies such as NASA-GSFC, NRAO, and NIST. MUSTANG carried out observations between 2008 and 2013 and will soon be replaced by a new receiver (MUSTANG-1.5). MUSTANG-1.5 is a 223-pixel array of feedhorn-coupled polarimeters, which are read out with a novel microwave SQUID multiplexer. MUSTANG-1.5 offers many advantages over MUSTANG including more stable cryogenics, a larger field of view (5.5' compared to 42" for MUSTANG), and a significant improvement in sensitivity. These capabilities enable a far more comprehensive observing program. MUSTANG is aimed at measuring the distortion in the Cosmic Microwave Background (CMB) spectrum that arises due to the Sunyaev-Zel'dovich Effect (SZE). The SZE is the inverse Compton-scattering of CMB photons as they pass through the dense plasma in clusters of galaxies. The SZE is a nearly redshift-independent, complementary probe of the ICM to X-ray emission and combined analyses of both data sets provide a better understanding of astrophysical phenomena such as shocks, cold fronts, and Active Galactic Nucleus (AGN) outbursts. Understanding how substructure, especially in merging clusters, affects the scaling between SZE flux and total cluster mass is essential to placing tight constraints on cosmological parameters with SZE surveys. In this thesis, I present some of the last ever observations carried out by MUSTANG, which are centered on two massive galaxy clusters, MACS J0647.7+7015 and MACS J1206.2-0847. I discuss a model-fitting technique that has been used to quantitatively compare MUSTANG and lower resolution SZE data from Bolocam to study ICM pressure profiles. I report on the design, commissioning, and current status of MUSTANG-1.5 including the detectors, cryogenics, optics, and the microwave multiplexing readout electronics. Finally, I present early characterization of the cryogenics and readout electronics as the instrument nears deployment-readiness and discuss plans for the early science program.

Book Interpreting High Resolution Sunyaev Zel dovich Effect Measurements with MUSTANG

Download or read book Interpreting High Resolution Sunyaev Zel dovich Effect Measurements with MUSTANG written by Charles Romero and published by . This book was released on 2015 with total page 480 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present pressure profiles of galaxy clusters determined from high resolutionSunyaev-Zel’dovich (SZ) effect observations in fourteen clusters, which span the red-shift range 0.25

Book Clusters of Galaxies Physics and Cosmology

Download or read book Clusters of Galaxies Physics and Cosmology written by Andrei M. Bykov and published by Springer. This book was released on 2020-10-31 with total page 535 pages. Available in PDF, EPUB and Kindle. Book excerpt: Clusters of galaxies are large assemblies of galaxies, hot gas and dark matter bound together by gravity. Galaxy clusters are now one of the most important cosmological probes to test the standard cosmological models. Constraints on the Dark Energy equation of state from the cluster number density measurements, deviations from the Gaussian perturbation models, the Sunyaev-Zeldovich effect as well as the dark matter proles are among the issues to be studied with clusters. The baryonic composition of clusters is dominated by hot gas that is in quasi-hydrostatic equilibrium within the dark matter-dominated gravitational potential well of the cluster. The hot gas is visible through spatially extended thermal X-ray emission, and it has been studied extensively both for assessing its physical properties and as a tracer of the large-scale structure of the Universe. Magnetic fields as well as a number of non-thermal plasma processes play a role in clusters of galaxies as we observe from radioastronomical observations. The goal of this volume is to review these processes and to investigate how they are interlinked. Overall, these papers provide a timely and comprehensive review of the multi-wavelength observations and theoretical understanding of clusters of galaxies in the cosmological context. Thus, the volume will be particularly useful to postgraduate students and researchers active in various areas of astrophysics and space science. Originally published in Space Science Reviews in the Topical Collection "Clusters of Galaxies: Physics and Cosmology"

Book Instrumentation and Analysis for Observations of the Sunyaev Zel dovich Effect from Galaxy Clusters with the APEX SZ Experiment

Download or read book Instrumentation and Analysis for Observations of the Sunyaev Zel dovich Effect from Galaxy Clusters with the APEX SZ Experiment written by James Kennedy and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "Clusters of galaxies are the largest gravitationally bound objects in the Universe. Their size makes them unique and powerful tools for cosmology and the study of astrophysical processes. The hot gas that resides between the galaxies constitutes the majority of the baryonic matter in the cluster, and can be detected through its emission processes as well as its effect on the cosmic microwave background (CMB) radiation in a process known as the Sunyaev-Zel'dovich effect (SZE).This thesis describes the Atacama Pathfinder EXperiment Sunyaev-Zel'dovich (APEX-SZ) project. This experiment was the first large-array TES bolometer instrument and observed galaxy clusters through the SZE. APEX-SZ employed 280 TES detectors and operated for 875 hours over five years, making targeted observations of 42 galaxy clusters. The scientific motivation for the APEX-SZ experiment is given, along with a description of the general instrumentation for a large-array TES bolometer receiver. In addition, an electronic temperature readout and control board, developed at McGill and operated by multiple CMB experiments, is presented. The data calibration and analysis of the APEX-SZ data is discussed, along with the SZE measurements from galaxy clusters and their scaling-relations with X-ray data." --

Book Measurement of Galaxy Cluster Integrated Comptonization and Mass Scaling Relations with the South Pole Telescope

Download or read book Measurement of Galaxy Cluster Integrated Comptonization and Mass Scaling Relations with the South Pole Telescope written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We describe a method for measuring the integrated Comptonization (Y (SZ)) of clusters of galaxies from measurements of the Sunyaev-Zel'dovich (SZ) effect in multiple frequency bands and use this method to characterize a sample of galaxy clusters detected in the South Pole Telescope (SPT) data. We use a Markov Chain Monte Carlo method to fit a [beta]-model source profile and integrate Y (SZ) within an angular aperture on the sky. In simulated observations of an SPT-like survey that include cosmic microwave background anisotropy, point sources, and atmospheric and instrumental noise at typical SPT-SZ survey levels, we show that we can accurately recover [beta]-model parameters for inputted clusters. We measure Y (SZ) for simulated semi-analytic clusters and find that Y (SZ) is most accurately determined in an angular aperture comparable to the SPT beam size. We demonstrate the utility of this method to measure Y (SZ) and to constrain mass scaling relations using X-ray mass estimates for a sample of 18 galaxy clusters from the SPT-SZ survey. Measuring Y (SZ) within a 0.'75 radius aperture, we find an intrinsic log-normal scatter of 21% ± 11% in Y (SZ) at a fixed mass. Measuring Y (SZ) within a 0.3 Mpc projected radius (equivalent to 0.'75 at the survey median redshift z = 0.6), we find a scatter of 26% ± 9%. Prior to this study, the SPT observable found to have the lowest scatter with mass was cluster detection significance. We demonstrate, from both simulations and SPT observed clusters that Y (SZ) measured within an aperture comparable to the SPT beam size is equivalent, in terms of scatter with cluster mass, to SPT cluster detection significance.

Book A Study of Large scale Structure Evolution Through Sunyaev Zel dovich Corrections in Massive Clusters

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.

Book Cool Core Bias in Sunyaev Zel dovich Galaxy Cluster Surveys

Download or read book Cool Core Bias in Sunyaev Zel dovich Galaxy Cluster Surveys written by and published by . This book was released on 2015 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sunyaev-Zeldovich (SZ) surveys find massive clusters of galaxies by measuring the inverse Compton scattering of cosmic microwave background off of intra-cluster gas. The cluster selection function from such surveys is expected to be nearly independent of redshift and cluster astrophysics. In this work, we estimate the effect on the observed SZ signal of centrally-peaked gas density profiles (cool cores) and radio emission from the brightest cluster galaxy (BCG) by creating mock observations of a sample of clusters that span the observed range of classical cooling rates and radio luminosities. For each cluster, we make simulated SZ observations by the South Pole Telescope and characterize the cluster selection function, but note that our results are broadly applicable to other SZ surveys. We find that the inclusion of a cool core can cause a change in the measured SPT significance of a cluster between 0.01%-10% at z> 0.3, increasing with cuspiness of the cool core and angular size on the sky of the cluster (i.e., decreasing redshift, increasing mass). We provide quantitative estimates of the bias in the SZ signal as a function of a gas density cuspiness parameter, redshift, mass, and the 1.4 GHz radio luminosity of the central AGN. Based on this work, we estimate that, for the Phoenix cluster (one of the strongest cool cores known), the presence of a cool core is biasing the SZ significance high by ~6%. The ubiquity of radio galaxies at the centers of cool core clusters will offset the cool core bias to varying degrees.

Book An Improved Measurement of the Hubble Constant Using the Sunyaev Zeldovich Effect

Download or read book An Improved Measurement of the Hubble Constant Using the Sunyaev Zeldovich Effect written by Brian Scott Mason and published by . This book was released on 1999 with total page 327 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Mass Calibration of the Sunyaev Zel dovich Effect Using APEX SZ Galaxy Clusters

Download or read book Mass Calibration of the Sunyaev Zel dovich Effect Using APEX SZ Galaxy Clusters written by Aarti Nagarajan and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book A Measurement of Gravitational Lensing of the Cosmic Microwave Background by Galaxy Clusters Using Data from the South Pole Telescope

Download or read book A Measurement of Gravitational Lensing of the Cosmic Microwave Background by Galaxy Clusters Using Data from the South Pole Telescope written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Clusters of galaxies are expected to gravitationally lens the cosmic microwave background (CMB) and thereby generate a distinct signal in the CMB on arcminute scales. Measurements of this effect can be used to constrain the masses of galaxy clusters with CMB data alone. Here we present a measurement of lensing of the CMB by galaxy clusters using data from the South Pole Telescope (SPT). We also develop a maximum likelihood approach to extract the CMB cluster lensing signal and validate the method on mock data. We quantify the effects on our analysis of several potential sources of systematic error and find that they generally act to reduce the best-fit cluster mass. It is estimated that this bias to lower cluster mass is roughly 0.85[sigma] in units of the statistical error bar, although this estimate should be viewed as an upper limit. Furthermore, we apply our maximum likelihood technique to 513 clusters selected via their Sunyaev-Zeldovich (SZ) signatures in SPT data, and rule out the null hypothesis of no lensing at 3.1[sigma]. The lensing-derived mass estimate for the full cluster sample is consistent with that inferred from the SZ flux: M200,lens = 0.83+0.38-0.37 M200,SZ (68% C.L., statistical error only).

Book The APEX SZ Experiment

Download or read book The APEX SZ Experiment written by James Kennedy and published by . This book was released on 2008 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt: