English
Related papers

Related papers: Cluster Abundance Constraints on Quintessence Mode…

200 papers

We present a method for determining the rms mass fluctuations on 8 h^-1 Mpc scale, sigma8. The method utilizes the rate of evolution of the abundance of rich clusters of galaxies. Using the Press-Schechter approximation, we show that the…

Astrophysics · Physics 2009-10-30 Xiaohui Fan , Neta A. Bahcall , Renyue Cen

We show that the evolution of the number density of rich clusters of galaxies breaks the degeneracy between Omega (the mass density ratio of the universe) and sigma_{8} (the normalization of the power spectrum), sigma_{8}Omega^{0.5} \simeq…

Astrophysics · Physics 2009-10-30 Neta A. Bahcall , Xiaohui Fan , Renyue Cen

We consider constraints on the amplitude of mass fluctuations in the universe, sigma_8, derived from two simple observations: the present number density of clusters and the amplitude of their correlation function. Allowing for the…

Astrophysics · Physics 2007-05-23 James Robinson , Eric Gawiser , Joseph Silk

In gaussian theories of structure formation, the galaxy cluster abundance is an extremely sensitive probe of the density fluctuation power spectrum and of the density parameter, $\Omega$. We develop this theme by deriving and studying in…

Astrophysics · Physics 2008-02-03 James G. Bartlett

We use the presently observed number density of large X-ray clusters and the linear mass power spectra to constrain $\sigma_8$ and the redshift distortion parameter $\beta$, in both OCDM and $\Lambda$CDM models. The best fit to the observed…

Astrophysics · Physics 2009-10-31 Jiun-Huei Proty Wu

The number density of rich galaxy clusters still provides the most robust way of normalizing the power spectrum of dark matter perturbations on scales relevant to large-scale structure. We revisit this constraint in light of several recent…

Astrophysics · Physics 2009-09-25 E. Pierpaoli , D. Scott , M. White

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 investigate the linear amplitude of mass fluctuations in the universe, $\sigma_8$, and the present mass density parameter of the Universe, $\Omega_\mathrm{m}$, from the statistical strong gravitational lensing. We use the two populations…

Astrophysics · Physics 2014-10-13 Da-Ming Chen

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

We investigate the gas mass function of clusters of galaxies to measure the density fluctuation spectrum on cluster scales. The baryon abundance confined in rich clusters is computed from the gas mass function and compared with the mean…

Astrophysics · Physics 2009-10-30 Kazuhiro Shimasaku

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

We use the present observed number density of large X-ray clusters to constrain the amplitude of matter density perturbations induced by cosmic strings on the scale of $8 h^{-1}$Mpc ($\sigma_8$), in both open cosmologies and flat models…

Astrophysics · Physics 2015-06-24 P. P. Avelino , J. H. P. Wu , E. P. S. Shellard

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 use the presently observed number density of large X-ray clusters and linear mass power spectra to constrain the shape parameter ($\Gamma$), the spectral index ($n$), the amplitude of matter density perturbations on the scale of $8…

Astrophysics · Physics 2010-12-13 Jiun-Huei Proty Wu

We use the abundance and weak lensing mass measurements of the SDSS maxBCG cluster catalog to simultaneously constrain cosmology and the richness--mass relation of the clusters. Assuming a flat \LambdaCDM cosmology, we find…

We investigate the dependence of cluster abundance $n(>M,r_{cl})$, i.e., the number density of clusters with mass larger than $M$ within radius $r_{cl}$, on scale parameter $r_{cl}$. Using numerical simulations of clusters in the CDM…

Astrophysics · Physics 2009-10-30 Wen Xu , Li-Zhi Fang , Xiang-Ping Wu

Abundance of rich clusters in local universe is currently believed to provide the most robust normalization of power spectrum at a scale of 10 Mpc. This normalization depends very sensitively on the calibration between virial mass M and…

Astrophysics · Physics 2009-11-07 Uros Seljak

We present an analysis of cosmological models with mixed dark matter (spectrum slope of density perturbations $n_S \in [0.6, 1.6]$, hot dark matter abundance $\Omega_\nu \in [0.0, 0.6]$) in spatially flat Universe, based on Press-Schechter…

Astrophysics · Physics 2011-04-15 N. A. Arkhipova , V. N. Lukash , E. V. Mikheeva

We use the halo model formalism to provide expressions for cluster abundances and bias, as well as estimates for the correlation matrix between these observables. Off-diagonal elements due to scatter in the mass tracer scaling with mass are…

Astrophysics · Physics 2011-05-12 Eduardo Rozo , Scott Dodelson , Joshua A. Frieman

A complete catalogue of galaxy cluster models can be used to constrain cosmological parameters like $\sigma_8$, the amplitude of the initial density fluctuation spectrum. We focus here on two strong lensing statistics for clusters of…

Astrophysics · Physics 2007-05-23 Eelco van Kampen
‹ Prev 1 2 3 10 Next ›