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Related papers: Constraining our Universe with X-ray & Optical Clu…

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We derive constraints on the mass-temperature relation of galaxy clusters from their observed luminosity-temperature relation and X-ray temperature function. Adopting the isothermal gas in hydrostatic equilibrium embedded in the universal…

Astrophysics · Physics 2009-11-07 Mamoru Shimizu , Tetsu Kitayama , Shin Sasaki , Yasushi Suto

Context. We present an estimation of cosmological parameters with clusters of galaxies. Aims. We constrain the $\Omega_m$, $\sigma_8$, and $w$ parameters from a stand-alone sample of X-ray clusters detected in the 50 deg$^2$ XMM-XXL survey…

X-ray observations of clusters provide key information on the dark matter, on the formation of structures in the Universe, and can be used to constrain the cosmological parameters. I review our current knowledge, with emphasis on recent XMM…

Astrophysics · Physics 2007-05-23 M. Arnaud

Combining conservation of energy throughout nearly-spherical collapse of galaxy clusters with the virial theorem, we derive the mass-temperature relation for X-ray clusters of galaxies $T=CM^{2/3}$. The normalization factor $C$ and the…

Astrophysics · Physics 2009-08-29 Niayesh Afshordi , Renyue Cen

We constrain gas and dark matter (DM) parameters of galaxy groups and clusters, by comparing X-ray scaling relations to theoretical expectations, obtained assuming that the gas is in hydrostatic equilibrium with the DM and follows a…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Pedro R. Capelo , Paolo S. Coppi , Priyamvada Natarajan

We derive constraints on the matter density \Om and the amplitude of matter clustering \sig8 from measurements of large scale weak lensing (projected separation R=5-30\hmpc) by clusters in the Sloan Digital Sky Survey MaxBCG catalog. The…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-11 Ying Zu , David H. Weinberg , Eduardo Rozo , Erin S. Sheldon , Jeremy L. Tinker , Matthew R. Becker

The amplitude of density perturbations, for the currently-favoured LambdaCDM cosmology, is constrained using the observed properties of galaxy clusters. The catalogue used is that of Ikebe et al. (2002). The cluster temperature to mass…

Astrophysics · Physics 2009-11-07 Pedro T P Viana , Scott T Kay , Andrew R Liddle , Orrarujee Muanwong , Peter A Thomas

This talk reviews the scientific motivations, the potential difficulty and recent advances in cosmology using cluster number-counts in the X-ray band. Our forward modelling approach shows that many of the practical and conceptual…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-12 Marguerite Pierre

We examine the likelihoods of different cosmological models and cluster evolutionary histories by comparing semi-analytical predictions of X-ray cluster number counts to observational data from the ROSAT satellite. We model cluster…

Astrophysics · Physics 2009-10-30 B. Mathiesen , A. E. Evrard

Even though the abundance and evolution of clusters have been used to study the cosmological parameters including the properties of dark energy owing to their pure dependence on the geometry of the Universe and the power spectrum, it is…

Cosmology and Nongalactic Astrophysics · Physics 2013-12-23 Seokcheon Lee , Kin-Wang Ng

Properties of high redshift clusters are a fundamental source of information for cosmology. It has been shown by Oukbir and Blanchard (1997) that the combined knowledge of the redshift distribution of X-ray clusters of galaxies and the…

Astrophysics · Physics 2011-05-23 R. Sadat , A. Blanchard , J. Oukbir

We re-examine the X-ray luminosity-temperature relation using a nearly homogeneous data set of 24 clusters selected for statistically accurate temperature measurements and absence of strong cooling flows. The data exhibit a remarkably tight…

Astrophysics · Physics 2009-10-30 Monique Arnaud , August E. Evrard

A tight mass-temperature relation, M(r)/r ~ T_X, is expected in most cosmological models if clusters of galaxies are homologous and the intracluster gas is in global equilibrium with the dark matter. We here calibrate this relation using 8…

Astrophysics · Physics 2009-10-30 Jens Hjorth , Jamila Oukbir , Eelco van Kampen

We present results of N-body/gasdynamical simulations designed to investigate the evolution of X-ray clusters in a flat, low-density, cold dark matter (CDM) cosmogony. The density profile of the dark matter component can be fitted rather…

Astrophysics · Physics 2009-10-30 Vincent R. Eke , Julio F. Navarro , Carlos S. Frenk

Using Chandra X-ray observations and optical imaging and spectroscopy of a flux-limited sample of 5 fossil groups, supplemented by additional systems from the literature, we provide the first detailed study of the scaling properties of…

Astrophysics · Physics 2008-11-26 Habib G. Khosroshahi , Trevor J. Ponman , Laurence R. Jones

We investigate the relationship between soft \xray luminosity and mass for low redshift clusters of galaxies by comparing observed number counts to expectations of $\Lambda$CDM cosmologies. We use a three-parameter model for the conditional…

Astrophysics · Physics 2008-11-26 R. Stanek , A. E. Evrard , H. Böhringer , P. Schuecker , B. Nord

We present weak gravitational lensing analysis of 22 high-redshift (z >~1) clusters based on Hubble Space Telescope images. Most clusters in our sample provide significant lensing signals and are well detected in their reconstructed…

We use the galaxy cluster X-ray temperature distribution function to constrain the amplitude of the power spectrum of density inhomogeneities on the scale corresponding to clusters. We carry out the analysis for critical density universes,…

Astrophysics · Physics 2015-06-24 Pedro T P Viana , Andrew R Liddle

The mass function of galaxy clusters is a powerful tool to constrain cosmological parameters, e.g., the mass fluctuation on the scale of 8 h^{-1} Mpc, sigma_8, and the abundance of total matter, Omega_m. We first determine the scaling…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Z. L. Wen , J. L. Han , F. S. Liu

We study the stellar cluster population in two adjacent fields in the nearby, face-on spiral galaxy, M83, using WFC3/HST imaging. The clusters are selected through visual inspection to be centrally concentrated, symmetric, and resolved on…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 N. Bastian , A. Adamo , M. Gieles , E. Silva Villa , H. J. G. L. M Lamers , S. S. Larsen , L. J. Smith , I. S. Konstantopoulos , E. Zackrisson