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Related papers: Using the Evolution of Clusters to Constrain Omega

200 papers

We present constraints on the mean matter density, Omega_m, the normalization of the density fluctuation power spectrum, sigma_8, and the dark-energy equation-of-state parameter, w, obtained from measurements of the X-ray luminosity…

Astrophysics · Physics 2010-02-03 A. Mantz , S. W. Allen , H. Ebeling , D. Rapetti

A new X-ray selected and X-ray flux-limited galaxy cluster sample is presented. Based on the ROSAT All-Sky Survey the 63 brightest clusters with galactic latitude |bII| >= 20 deg and flux fx(0.1-2.4 keV) >= 2 * 10^{-11} ergs/s/cm^2 have…

Astrophysics · Physics 2011-02-11 Thomas H. Reiprich , Hans Boehringer

The ROSAT Deep Cluster Survey (RDCS) has provided a new large deep sample of X-ray selected galaxy clusters. Observables such as the flux number counts n(S), the redshift distribution n(z) and the X-ray luminosity function (XLF) over a…

Astrophysics · Physics 2009-10-31 S. Borgani , P. Rosati , P. Tozzi , C. Norman

We carry out N-body simulations of several non-Gaussian structure formation models, including Peebles' isocurvature cold dark matter model, cosmic string models, and a model with primordial voids. We compare the evolution of the cluster…

Astrophysics · Physics 2009-10-31 James Robinson , Jonathan E. Baker

The upcoming XMM Large Scale Structure Survey (XMM-LSS) will ultimately provide a unique mapping of the distribution of X-ray sources in a contiguous 64 sq. deg. region. In particular, it will provide the 3-dimensional location of about 900…

Astrophysics · Physics 2009-11-07 Alexandre Refregier , Ivan Valtchanov , Marguerite Pierre

We investigate the redshift evolution of the matter density parameter, $\Omega_m(z)$, using galaxy cluster gas mass fraction measurements combined with cosmic chronometer $H(z)$ data and type Ia supernova luminosity distances. Our approach…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-30 R. F. L. Holanda , J. F. Jesus , Z. C. Santana , R. C. Nunes

We present precise constraints on the normalization of the power spectrum of mass fluctuations in the nearby universe, sigma_8, as a function of the mean local matter density, Omega_m. Using the observed local X-ray luminosity function of…

Astrophysics · Physics 2008-11-26 S. W. Allen , R. W. Schmidt , A. C. Fabian , H. Ebeling

The observed evolution of the galaxy cluster X-ray integral temperature distribution function between $z=0.05$ and $z=0.32$ is used in an attempt to constrain the value of the density parameter, $\Omega_{0}$, for both open and…

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

We determine the linear amplitude of mass fluctuations in the universe, sigma_8, from the abundance of massive clusters at redshifts z=0.5 to 0.8. The evolution of massive clusters depends exponentially on the amplitude of mass fluctuations…

Astrophysics · Physics 2009-11-07 Neta A. Bahcall , Paul Bode

We present an analysis of the clustering evolution of dark matter in four cold dark matter (CDM) cosmologies. We use a suite of high resolution, 17-million particle, N-body simulations which sample volumes large enough to give clustering…

We present a self-consistent approach to the modeling of X-ray clusters of galaxies in a flat universe. Employing the Press and Schechter (1974) formalism to derive the mass function and relating the observable properties of clusters to…

Astrophysics · Physics 2016-08-30 J. Oukbir , J. G. Bartlett , A. Blanchard

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

The redshift dependence of the observed cluster abundance due to the Sunyaev-Zeldovich Effect (SZE) is studied in various cosmological models including flat and open homogeneous (CDM) models and an inhomogeneous model with a large-scale…

Astrophysics · Physics 2009-11-07 Kenji Tomita

The motions of galaxies can be used to constrain the cosmological density parameter Omega and the clustering amplitude of matter on large scales. The mean relative velocity of galaxy pairs, estimated from the Mark III survey, indicates that…

Astrophysics · Physics 2009-10-31 R. Juszkiewicz , P. G. Ferreira , H. A. Feldman , A. H. Jaffe , M. Davis

We calculate the number of damped Lyman-alpha absorbers expected in various popular cosmological models as a function of redshift and compare our predictions with observed abundances. The Press-Schechter formalism is used to obtain the…

Astrophysics · Physics 2009-10-30 Jeffrey P. Gardner , Neal Katz , David H. Weinberg , Lars Hernquist

In hierarchical cosmologies the evolution of galaxy clustering depends both on cosmological quantities such as Omega and Lambda, which determine how dark matter halos form and evolve, and on the physical processes - cooling, star formation…

We estimate the value of the matter density parameter \Omega_0 by combining constraints from the galaxy cluster mass function with Croft et al.'s recent measurement of the mass power spectrum, P(k), from \lya forest data. The key assumption…

Astrophysics · Physics 2009-10-31 David H. Weinberg , Rupert A. C. Croft , Lars Hernquist , Neal Katz , Max Pettinini

We show that the counts of galaxy clusters in future deep cluster surveys can place strong constraints on the matter density, Omega_m, the vacuum energy density, Omega_L, and the normalization of the matter power spectrum, sigma_8.…

Astrophysics · Physics 2011-05-05 Gilbert Holder , Zoltan Haiman , Joseph Mohr

The large-scale structure in the distribution of galaxies is thought to arise from the gravitational instability of small fluctuations in the initial density field of the universe. A key test of this hypothesis is that superclusters of…

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