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Related papers: Galaxy clusters, type Ia supernovae and the fine s…

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We present observations from the Small Array of the Arcminute Microkelvin Imager (AMI) of eight high X-ray luminosity galaxy cluster systems selected from the Local Cluster Substructure Survey (LoCuSS) sample.We detect the…

We explore the systematic uncertainties of using Type Ia supernovae (SNe Ia) as cosmological probes, using the Supernova Legacy Survey Three Year data (SNLS3). We focus on studying the possible evolution of the stretch-luminosity parameter…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-07 Shuang Wang , Yun Wang

We present a new application of deep learning to infer the masses of galaxy clusters directly from images of the microwave sky. Effectively, this is a novel approach to determining the scaling relation between a cluster's Sunyaev-Zel'dovich…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-16 Nikhel Gupta , Christian L. Reichardt

Not much by themselves, aparently. We try to reconstruct the scale factor $a(t)$ of the universe from the SNe Ia data, i.e. the luminosity distance $d_{L}(z)$, using only the cosmological principle and the assumption that gravitation is…

General Relativity and Quantum Cosmology · Physics 2017-06-19 İbrahim Semiz , A. Kazım Çamlıbel

Measurements of the Sunyaev-Zel'dovich (hereafter SZ) effect distortion of the cosmic microwave background provide methods to derive the gas pressure and temperature of galaxy clusters. Here we study the ability of SZ effect observations to…

High Energy Astrophysical Phenomena · Physics 2015-05-28 D. A. Prokhorov , S. Colafrancesco , T. Akahori , K. Yoshikawa , S. Nagataki , K. -I. Seon

We present gas mass fractions of 38 massive galaxy clusters spanning redshifts from 0.14 to 0.89, derived from Chandra X-ray data and OVRO/BIMA interferometric Sunyaev-Zel'dovich Effect measurements. We use three models for the gas…

Astrophysics · Physics 2008-11-26 S. LaRoque , M. Bonamente , J. Carlstrom , M. Joy , D. Nagai , E. Reese , K. Dawson

Observations of clusters in the 30 to 350 GHz range can in principle be used to determine a galaxy cluster's Comptonization parameter, y, peculiar velocity, v and gas temperature, T_e via the dependence of the kinetic and thermal…

Astrophysics · Physics 2009-11-10 Lloyd Knox , Gil Holder , Sarah Church

Using the BSBM varying-alpha theory, with dark matter dominated by magnetic energy, and the spherical collapse model for cosmological structure formation, we have studied the effects of the dark-energy equation of state and the coupling of…

Astrophysics · Physics 2009-11-10 D. F. Mota , J. D. Barrow

The determination of the mass of galaxy clusters from observations is subject to systematic uncertainties. Beyond the errors due to instrumental and observational systematic effects, in this work we investigate the bias introduced by…

The Sunyaev-Zel'dovich effect provides a useful probe of cosmology and structure formation in the Universe. Recent years have seen rapid progress in both quality and quantity of its measurements. In this review, we overview cosmological and…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-02 Tetsu Kitayama

Bekenstein's model of a scalar field, \phi, that affects the electromagnetic permeability (usually identified with ``changing \alpha'') predicts tiny variations of the effective fine structure constant up to very high red-shifts,…

High Energy Physics - Phenomenology · Physics 2009-09-15 Keith A. Olive , Maxim Pospelov

In addition to cosmological tests based on the mass function and clustering of galaxy clusters, which probe the growth of cosmic structure, nature offers two independent ways of using clusters to measure cosmic distances. The first uses…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-01 S. W. Allen , A. B. Mantz , R. G. Morris , D. E. Applegate , P. L. Kelly , A. von der Linden , D. A. Rapetti , R. W. Schmidt

We have measured the equivalent width of the H-alpha emission line for 11006 galaxies brighter than M_b=-19 (LCDM) at 0.05<z<0.1 in the 2dF Galaxy Redshift Survey (2dF), in the fields of seventeen known galaxy clusters. The limited redshift…

We present imaging simulations of the Sunyaev-Zel'dovich effect of galaxy clusters for the Atacama Large Millimeter/submillimeter Array (ALMA) including the Atacama Compact Array (ACA). In its most compact configuration at 90GHz, ALMA will…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 K. Yamada , T. Kitayama , S. Takakuwa , D. Iono , T. Tsutsumi , K. Kohno , M. Takizawa , K. Yoshikawa , T. Akahori , E. Komatsu , Y. Suto , H. Matsuo , R. Kawabe

Under very general assumptions of metric theory of spacetime, photons traveling along null geodesics and photon number conservation, two observable concepts of cosmic distance, i.e. the angular diameter and the luminosity distances are…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-16 Kai Liao , Zhengxiang Li , Shuo Cao , Marek Biesiada , Xiaogang Zheng , Zong-Hong Zhu

We discuss a new method of finding the cluster temperatures which is independent of distance and therefore very useful for distant clusters. The hot gas of electrons in clusters of galaxies scatters and distorts the cosmic microwave…

Astrophysics · Physics 2009-11-07 Steen H. Hansen , Sergio Pastor , Dmitry V. Semikoz

(Abridged) We use two very large cosmological simulations to study how the density profiles of relaxed LCDM dark halos depend on redshift and on halo mass. We confirm that these profiles deviate slightly but systematically from the NFW form…

We obtain constraints on the variation of the fundamental constants from the full shape of the redshift-space correlation function of a sample of luminous galaxies drawn from the Data Release 9 of the Baryonic Oscillations Spectroscopic…

The scatter in the apparent magnitude of type Ia supernovae induced by stochastic gravitational lensing is highly dependent on the nonlinear growth of cosmological structure. In this paper, we show that such a dependence can potentially be…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Cosimo Fedeli , Lauro Moscardini
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