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Cosmologies including continuous matter creation are able to reproduce the main properties of the standard $\Lambda$CDM model, in particular in cases where the particle and entropy production rates are equal. These specific models,…

General Relativity and Quantum Cosmology · Physics 2011-03-07 Alain de Roany , J. A. de Freitas Pacheco

We present a new model for the redshift-space power spectrum of galaxies and demonstrate its accuracy in modeling the monopole, quadrupole, and hexadecapole of the galaxy density field down to scales of $k = 0.4 \ h\mathrm{Mpc}^{-1}$. The…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-18 Nick Hand , Uros Seljak , Florian Beutler , Zvonimir Vlah

We present cosmological parameter measurements from the publicly available Baryon Oscillation Spectroscopic Survey (BOSS) data on anisotropic galaxy clustering in Fourier space. Compared to previous studies, our analysis has two main novel…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-28 Mikhail M. Ivanov , Marko Simonović , Matias Zaldarriaga

In the standard Lambda CDM cosmological model with a Gaussian primordial density fluctuation field, the relatively low value of the mass variance parameter (sigma_8=0.74{+0.05}{-0.06}, obtained from the WMAP 3-year data) results in a…

Astrophysics · Physics 2009-06-23 S. Sadeh , Y. Rephaeli , J. Silk

Aims. We analyze the clustering of galaxy clusters in a large contiguous sample, the Constrain Dark Energy with X-ray (CODEX) sample. We construct a likelihood for cosmological parameters by comparing the measured clustering signal and a…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-11 Valtteri Lindholm , Alexis Finoguenov , Andrés Balaguera-Antolínez , Tiago Castro

We explore the potential of cross-correlating galaxies and peculiar velocities on non-linear scales to enhance cosmological constraints. Leveraging the \textsc{AbacusSummit} simulation suite and the halo occupation distribution (HOD)…

We present a Fourier analysis of the clustering of galaxies in the combined Main galaxy and Luminous Red Galaxy (LRG) Sloan Digital Sky Survey (SDSS) Data Release 5 (DR5) sample. The aim of our analysis is to consider how well we can…

Using high-dispersion spectra from the HIRES echelle spectrograph on the Keck I telescope, we measure velocity dispersions for 4 globular clusters in M33. Combining the velocity dispersions with integrated photometry and structural…

Astrophysics · Physics 2009-11-07 S. S. Larsen , J. P. Brodie , A. Sarajedini , J. P. Huchra

We present a simple model for the shape of the distribution function of galaxy peculiar velocities. We show how both nonlinear and linear theory terms combine to produce a distribution which has an approximately Gaussian core with…

Astrophysics · Physics 2009-10-31 Ravi K. Sheth , Antonaldo Diaferio

We compare the distribution of internal velocity dispersions of galaxy clusters for an observational sample to those obtained from a set of N-body simulations of seven COBE-normalised cosmological scenarios: the standard CDM (SCDM) and a…

Astrophysics · Physics 2009-10-30 S. Borgani , A. Gardini , M. Girardi , S. Gottloeber

We present clustering measurements for samples of galaxies selected by morphological type and luminosity from the recently completed Stromlo-APM Redshift Survey. Early type galaxies are clustered more strongly by a factor 3.5--5.5, than…

Astrophysics · Physics 2009-10-22 J. Loveday , S. J. Maddox , G. Efstathiou , B. A. Peterson

We have investigated the peculiar motions of clusters of galaxies in the Ursa Major (UMa) supercluster and its neighborhood. Based on SDSS (Sloan Digital Sky Survey) data, we have compiled a sample of early-type galaxies and used their…

Astrophysics · Physics 2009-06-23 Flera G. Kopylova , Alexander I. Kopylov

Low amplitude (linear regime) cosmic density fluctuations lead to spatial variations in the locally measurable value of $H_0$ (denoted as $H_L$), $\delta_H \equiv (H_L-H_0)/H_0$, which are of order 3-6% (95% confidence interval) in a sphere…

Astrophysics · Physics 2009-10-30 Yun Wang , David N. Spergel , Edwin L. Turner

The peculiar radial velocities of eight clusters of galaxies, as determined from a variety of distance indicators, are consistent with a bulk flow not greatly different in direction and magnitude from the velocity vector of the Local Group…

Astrophysics · Physics 2007-05-23 Donald H. Gudehus

Galaxy clusters are biased tracers of the underlying matter density field. At very large radii beyond about 10 Mpc/\textit{h}, the shear profile shows evidence of a second-halo term. This is related to the correlated matter distribution…

We present a comparison of Abell and APM clusters of galaxies as tracers of the large scale structure of the Universe. We investigate selection functions of both cluster catalogs. We show that the supercluster-void network can be traced…

Astrophysics · Physics 2009-10-31 M. Einasto , J. Einasto , E. Tago , H. Andernach , G. B. Dalton , V. M"uller

We allow for nonlinear effects in the likelihood analysis of galaxy peculiar velocities, and obtain ~35%-lower values for the cosmological density parameter Om and the amplitude of mass-density fluctuations. The power spectrum in the linear…

Astrophysics · Physics 2009-11-06 L. Silberman , A. Dekel , A. Eldar , I. Zehavi

We present the analysis of the color-magnitude relation (CMR) for a sample of 57 X-ray detected Abell clusters within the redshift interval 0.02 <= z <= 0.18. We use the B-R vs R color-magnitude plane to establish that the CMR is present in…

Astrophysics · Physics 2009-11-10 Omar Lopez-Cruz , Wayne A. Barkhouse , H. K. C. Yee

Future X-ray observations of galaxy clusters by high spectral resolution missions will provide spatially resolved measurements of the energy and width for the brightest emission lines in the intracluster medium (ICM) spectrum. In this paper…

High Energy Astrophysical Phenomena · Physics 2015-06-04 I. Zhuravleva , E. Churazov , A. Kravtsov , R. Sunyaev

We use measurements of the galaxy-cluster angular size versus redshift to test and compare the standard model (LCDM) and the R_h=ct Universe. We show that the latter fits the data with a reduced chi^2_dof=0.786 for a Hubble constant H_0=…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-25 Jun-Jie Wei , Xue-Feng Wu , Fulvio Melia
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