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相关论文: Constraints on Omega_m, Omega_L, and Sigma_8, from…

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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…

天体物理学 · 物理学 2010-02-03 A. Mantz , S. W. Allen , H. Ebeling , D. Rapetti

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…

天体物理学 · 物理学 2008-11-26 S. W. Allen , R. W. Schmidt , A. C. Fabian , H. Ebeling

We use three strong lensing clusters to constrain the cosmological parameters Omega_m and Omega_lambda. Recent HST observations of galaxy clusters reveal a large number of multiple images, which are predicted to be at different redshifts.…

天体物理学 · 物理学 2007-05-23 G. Golse , J. -P. Kneib , G. Soucail

The CNOC redshift survey of galaxy clusters measures Omega_M from Omega_e(z)= M/L x j/\rho_c which can be applied on a cluster-by-cluster basis. The mass-to-light ratios, M/L, are estimated from rich galaxy clusters, corrected to the field…

The existence of the three most massive clusters of galaxies observed so far at z>0.5 is used to constrain the mass density parameter of the universe, Omega, and the amplitude of mass fluctuations, sigma_8. We find Omega=0.2 (+0.3,-0.1),…

天体物理学 · 物理学 2011-05-05 Neta A. Bahcall , Xiaohui Fan

We investigate the potentiality of using strong lensing clusters to constrain the cosmological parameters Omega_m and Omega_lambda. The existence of a multiple image system with known redshift allows, for a given (Omega_m, Omega_lambda)…

天体物理学 · 物理学 2009-11-06 G. Golse , J. -P. Kneib , G. Soucail

We place constraints on the average density (Omega_m) and clustering amplitude (sigma_8) of matter using a combination of two measurements from the Sloan Digital Sky Survey: the galaxy two-point correlation function, w_p, and the…

[Abridged] We use data on massive galaxy clusters ($M_{\rm cluster} > 8 \times 10^{14} h^{-1} M_\odot$ within a comoving radius of $R_{\rm cluster} = 1.5 h^{-1}\Mpc$) in the redshift range $0.05 \lesssim z \lesssim 0.83$ to place…

宇宙学与河外天体物理 · 物理学 2015-05-30 L. Campanelli , G. L. Fogli , T. Kahniashvili , A. Marrone , Bharat Ratra

We study the expected redshift evolution of galaxy cluster abundance between 0 < z < 3 in different cosmologies, including the effects of the cosmic equation of state parameter w=p/rho. Using the halo mass function obtained in recent large…

天体物理学 · 物理学 2011-05-05 Zoltan Haiman , Joseph J. Mohr , Gilbert P. Holder

We demonstrate that constraints on cosmological parameters from the distribution of clusters as a function of redshift (dN/dz) are complementary to accurate angular diameter distance (D_A) measurements to clusters, and their combination…

天体物理学 · 物理学 2009-11-10 S. M. Molnar , Z. Haiman , M. Birkinshaw , R. F. Mushotzky

The number of rich galaxy clusters per unit volume is a strong function of Omega, the cosmological density parameter, and sigma_8, the linear extrapolation to z=0 of the density contrast in 8/h Mpc spheres. The CNOC cluster redshift survey…

天体物理学 · 物理学 2009-10-28 R. G. Carlberg , S. L. Morris , H. K. C. Yee , E. Ellingson

The properties of nearby galaxy clusters limit the range of cosmological parameters consistent with our universe. We describe the limits which arise from studies of the intracluster medium (ICM) mass fraction fICM and consideration of the…

天体物理学 · 物理学 2016-11-03 Joseph J. Mohr , Zoltan Haiman , Gilbert P. Holder

A precise determination of the mass function is an important tool to verify cosmological predictions of the $\Lambda$CDM model and to infer more precisely the better model describing the evolution of the Universe. Galaxy clusters have been…

宇宙学与河外天体物理 · 物理学 2016-11-15 Ahmad Mehrabi , Francesco Pace , Mohammad Malekjani , Antonino Del Popolo

We forecast constraints on the amplitude of matter clustering sigma_8(z) achievable with the combination of cluster weak lensing and number counts, in current and next-generation weak lensing surveys. We advocate an approach, analogous to…

宇宙学与河外天体物理 · 物理学 2021-03-29 Hao-Yi Wu , David H. Weinberg , Andrés N. Salcedo , Benjamin D. Wibking

In recent years, the availability of large, complete cluster samples has enabled numerous cosmological parameter inference analyses using cluster number counts. These have provided constraints on the cosmic matter density $\Omega_m$ and the…

宇宙学与河外天体物理 · 物理学 2021-11-23 P. S. Corasaniti , M. Sereno , S. Ettori

We present constraints on the values of $\Omega_m$, $n$, $\sigma_8$, obtained from measurements of the X-ray luminosity function of galaxy clusters as compiled in EMSS, RDCS and BCS galaxy cluster samples. The values obtained…

宇宙学与河外天体物理 · 物理学 2009-06-23 A. Del Popolo

We present cosmological constraints from the Dark Energy Survey (DES) using a combined analysis of angular clustering of red galaxies and their cross-correlation with weak gravitational lensing of background galaxies. We use a 139 square…

Chandra observations of large samples of galaxy clusters detected in X-rays by ROSAT provide a new, robust determination of the cluster mass functions at low and high redshifts. Statistical and systematic errors are now sufficiently small,…

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…

宇宙学与河外天体物理 · 物理学 2015-05-18 Z. L. Wen , J. L. Han , F. S. Liu

We use the X-ray power spectrum of the ROSAT all-sky survey in the R6 band (approximately 0.9-1.3 keV) to set an upper limit on the galaxy cluster power spectrum. The cluster power spectrum is modelled with a minimum number of robust…

天体物理学 · 物理学 2009-11-07 J. M. Diego , W. Sliwa , J. Silk , X. Barcons , W. Voges
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