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Related papers: Measuring Omega with Galaxy Streaming Velocities

200 papers

We present a general analytical formalism to calculate accurately several statistics related to underdense regions in the Universe. The statistics are computed for dark matter halo and galaxy distributions both in real space and redshift…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Juan Betancort-Rijo , Santiago G. Patiri , Francisco Prada , Antonio Enea Romano

The streaming model describes the mapping between real and redshift space for 2-point clustering statistics. Its key element is the probability density function (PDF) of line-of-sight pairwise peculiar velocities. Following a kinetic-theory…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-24 Joseph Kuruvilla , Cristiano Porciani

In General Relativity, the average velocity field of dark matter around galaxy clusters is uniquely determined by the mass profile. The latter can be measured through weak lensing. We propose a new method of measuring the velocity field…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Tsz Yan Lam , Takahiro Nishimichi , Fabian Schmidt , Masahiro Takada

We re-examine the technique of determining the redshifts of galaxies from the ratio of the submillimeter-to-radio continuum flux densities based on a recently published catalog of 850~$\mu$m sources. We derived the expected variation of…

Astrophysics · Physics 2015-06-24 T. N. Rengarajan , Tsutomu T. Takeuchi

We have measured for the first time the weak lensing signal due to groups of galaxies. The groups are at intermediate redshifts, and have been identified in the CNOC2 field survey, which was kindly made available by Ray Carlberg and Howard…

Astrophysics · Physics 2007-05-23 Henk Hoekstra , Marijn Franx , Konrad Kuijken

Redshift maps of galaxies in the Universe are distorted by the peculiar velocities of galaxies along the line of sight. The amplitude of the distortions on large, linear scales yields a measurement of the linear redshift distortion…

Astrophysics · Physics 2016-01-27 A. J. S. Hamilton

Cosmological parameters can be measured by comparing peculiar velocities with those predicted from a galaxy density field. Previous work has tested the accuracy of this approach with N-body simulations, but generally on idealised mock…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-27 Amber M. Hollinger , Michael J. Hudson

We compare the peculiar velocities measured in the SBF Survey of Galaxy Distances with the predictions from the density fields of the IRAS 1.2 Jy flux-limited redshift survey and the Optical Redshift Survey (ORS) to derive simultaneous…

Astrophysics · Physics 2009-10-31 J. P. Blakeslee , M. Davis , J. L. Tonry , A. Dressler , E. A. Ajhar

The redshift of all cosmological sources drifts by a systematic velocity of order a few m/s over a century due to the deceleration of the Universe. The specific functional dependence of the predicted velocity shift on the source redshift…

Astrophysics · Physics 2011-02-11 Abraham Loeb

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…

Astrophysics · Physics 2009-10-28 R. G. Carlberg , S. L. Morris , H. K. C. Yee , E. Ellingson

We discuss methods that can be used to estimate the spatial correlation length r_0 of galaxy samples from the observed number of pairs with similar redshifts. The standard method is unnecessarily noisy and can be compromised by errors in…

Astrophysics · Physics 2009-11-10 Kurt L. Adelberger

One of the main problems of observational cosmology is to determine the range in which a reliable measurement of galaxy correlations is possible. This corresponds to determine the shape of the correlation function, its possible evolution…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-18 Francesco Sylos Labini , Daniil Tekhanovich , Yurij V. Baryshev

We examine the nature of galaxy clustering in redshift space using a method based on an expansion of the galaxian density field in Spherical Harmonics and linear theory. We derive a compact and self-consistent expression for the distortion…

Astrophysics · Physics 2007-05-23 Karl B. Fisher

The distribution of early-type galaxy velocity dispersions, phi(sigma), is measured using a sample drawn from the SDSS database. Its shape differs significantly from that which one obtains by simply using the mean correlation between…

We have studied the galaxy-group cross-correlations in redshift space for the Galaxy And Mass Assembly (GAMA) Survey. We use a set of mock GAMA galaxy and group catalogues to develop and test a novel 'halo streaming' model for…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-21 Qianjun Hang , John A. Peacock , Shadab Alam , Yan-Chuan Cai , Katarina Kraljic , Marcel van Daalen , M. Bilicki , B. W. Holwerda , J. Loveday

The velocity dispersion of galaxies on small scales ($r\sim1h^{-1}$ Mpc), $\sigma_{12}(r)$, can be estimated from the anisotropy of the galaxy-galaxy correlation function in redshift space. We apply this technique to ``mock-catalogs''…

Astrophysics · Physics 2009-10-28 Rachel S. Somerville , Joel R. Primack , Richard Nolthenius

The redshifts of lens galaxies in known gravitational lens systems probe the volume distribution of lensing mass. Following earlier work by Kochanek, we re-derive the lens redshift probability distribution, allowing for mass and number…

Astrophysics · Physics 2009-11-07 Eran O. Ofek , Hans-Walter Rix , Dan Maoz

We study the possibility of using correlations between spatial modulations in the observed luminosity distribution of galaxies and the underlying density field as a cosmological probe. Considering redshift ranges, where magnification…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-07 Martin Feix

Hubble Space Telescope images of high-redshift galaxies selected via color and photometric redshifts are used to examine the size and axial-ratio distribution of galaxies as a function of redshift at lookback times t > 8 Gyr. These…

Measuring the statistics of galaxy peculiar velocities using redshift-space distortions is an excellent way of probing the history of structure formation. Because galaxies are expected to act as test particles within the flow of matter,…

Astrophysics · Physics 2010-04-22 Yong-Seon Song , Will J. Percival