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Related papers: Peculiar Velocities and the Mean Density Parameter

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This is the second in a series of papers in which we compare Tully-Fisher (TF) data from the Mark III Catalog with predicted peculiar velocities based on the IRAS galaxy redshift survey and gravitational instability theory, using a rigorous…

Astrophysics · Physics 2009-10-30 Jeffrey A. Willick , Michael A. Strauss

Using the 2MASS near-infrared photometry and high signal-to-noise HI 21-cm data from the Arecibo, Green Bank, Nancay, and Parkes telescopes, we calculate the redshift-independent distances and peculiar velocities of 2,018 bright inclined…

The reconstruction of the peculiar velocity field from the 1.936~Jy iras selected sample of galaxies is compared to a similar reconstruction from an optically selected sample. A general method for combining different samples to reconstruct…

Astrophysics · Physics 2015-06-24 Wolfram Freudling , Luiz Nicolaci da Costa , Paulo S. Pellegrini

We present an analysis of the ENEAR sample of peculiar velocities of elliptical galaxies, obtained with D_n-\sigma distances. We use the velocity correlation function to analyze the statistics of the field-object's velocities, while the…

Recent progress in the measurement of relative distances to galaxies has been quite substantial, and catalogs of 3000 galaxies with distances are soon to become available. The peculiar {\it velocity} field (deviations from Hubble flow)…

Astrophysics · Physics 2016-08-30 Marc Davis , Adi Nusser

We present a maximum probability approach to reconstructing spatial maps of the peculiar velocity field at redshifts $z\sim0.1$, where the velocities have been measured from distance indicators (DI) such as $D_n-\sigma$ relations or…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-18 Russell Johnston , David Bacon , Luis F. A. Teodoro , Robert C. Nichol , Michael S. Warren , Catherine Cress

This article explores three usual estimators, noted as $v_{12}$ of the pairwise velocity, $\psi_1$ and $\psi_2$ of the observed two-point galaxy peculiar velocity correlation functions. These estimators are tested on mock samples of {\it…

Cosmology and Nongalactic Astrophysics · Physics 2019-04-10 A. Dupuy , H. M. Courtois , B. Kubik

Measurement of peculiar velocities by combining redshifts and distance indicators is a powerful way to measure the growth rate of cosmic structure and test theories of gravity at low redshift. Here we constrain the growth rate of structure…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-22 Khaled Said , Matthew Colless , Christina Magoulas , John R. Lucey , Michael J. Hudson

The relative pair dispersion of galaxies has for the past decade been the standard measure of the thermal energy of fluctuations in the observed galaxy distribution. This statistic is known to be unstable, since it is a pair-weighted…

Astrophysics · Physics 2009-10-30 Marc Davis , Amber Miller , Simon D. M. White

We compare infrared Tully-Fisher (TF) distances and peculiar velocities derived for spiral galaxies from the two largest datasets: the 2MASS selected Flat Galaxy Catalog, 2MFGC [19, 20] and the Arecibo General Catalog with I-band…

The power spectrum of mass density fluctuations is evaluated from the Mark III and the SFI catalogs of peculiar velocities by a maximum likelihood analysis, using parametric models for the power spectrum and for the errors. The applications…

Astrophysics · Physics 2007-05-23 Idit Zehavi , Avishai Dekel

Peculiar velocities are an important probe of the growth rate of mass density fluctuations in the Universe. Most previous studies have focussed exclusively on measuring peculiar velocities at intermediate ($0.2 < z < 1$) redshifts using…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Michael J. Hudson , Stephen J. Turnbull

Galaxy cluster peculiar velocities can be inferred from high-sensitivity, high-resolution multiple-frequency observations in the 30 to 400 GHz range. While galaxy cluster counts and power spectra are sensitive to the growth factor, peculiar…

Astrophysics · Physics 2009-11-07 A. Peel , L. Knox

Using mean relative peculiar velocity measurements for pairs of galaxies, we estimate the cosmological density parameter $\Omega_m$ and the amplitude of density fluctuations $\sigma_8$. Our results suggest that our statistic is a robust and…

We develop new methods to study the properties of galaxy redshift surveys and radial peculiar velocity surveys, both individually and combined. We derive the Fisher information matrix for redshift surveys, including redshift distortions and…

Astrophysics · Physics 2009-11-10 Daniel Burkey , Andy Taylor

We have investigated the possibility of inferring peculiar velocities for clusters of galaxies from the Doppler shift of scattered cosmic microwave background (CMB) photons. We find that if the core radius of the gas distribution or the…

Astrophysics · Physics 2015-06-24 Martin G. Haehnelt , Max Tegmark

We constructed a Bayesian hyper-parameter statistical method to quantify the difference between predicted velocities derived from the observed galaxy distribution in the \textit{IRAS}-PSC$z$ redshift survey and peculiar velocities measured…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Yin-Zhe Ma , Enzo Branchini , Douglas Scott

The peculiar velocity field of the local Universe provides direct insights into its matter distribution and the underlying theory of gravity, and is essential in cosmological analyses for modelling deviations from the Hubble flow. Numerous…

The peculiar velocity function of clusters of galaxies is determined using an accurate sample of cluster velocities based on Tully-Fisher distances of Sc galaxies (Giovanelli et al 1995b). In contrast with previous results based on samples…

Astrophysics · Physics 2009-10-28 Neta A. Bahcall , Siang Peng Oh

We present the first results from the Shellflow program, an all-sky Tully-Fisher (TF) peculiar velocity survey of 276 Sb-Sc galaxies with redshifts between 4500 and 7000 km/s. Shellflow was designed to minimize systematic errors between…

Astrophysics · Physics 2009-10-31 S. Courteau , J. A. Willick , M. A. Strauss , D. Schlegel , M. Postman