English
Related papers

Related papers: Extracting local velocity from cosmic dipole using…

200 papers

Galaxy peculiar velocities provide an integral source of cosmological information that can be harnessed to measure the growth rate of large scale structure and constrain possible extensions to General Relativity. In this work, we present a…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-30 Ryan J. Turner , Chris Blake , Rossana Ruggeri

The angular distribution of the Cosmic Microwave Background Radiation (CMBR) in sky shows a dipole asymmetry, ascribed to the observer's motion (peculiar velocity of the solar system!), relative to the local comoving coordinates. The…

General Physics · Physics 2019-09-11 Ashok K. Singal

We quantify the expected observed statistical and systematic uncertainties of the escape velocity as a measure of the gravitational potential and total mass of galaxy clusters. We focus our attention on low redshift (z < 0.15) clusters,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Daniel Gifford , Christopher J. Miller , Nicholas Kern

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

We obtain the dipolar anisotropies in the arrival directions of ultra-high energy cosmic rays diffusing from nearby extragalactic sources. We discuss both the energy regime of spatial diffusion and the quasi-rectilinear one leading to just…

High Energy Astrophysical Phenomena · Physics 2014-06-11 Diego Harari , Silvia Mollerach , Esteban Roulet

We investigate the properties of the pairwise velocity dispersion as a function of galaxy luminosity in the context of a halo model. We derive the distribution of velocities of pairs at a given separation taking into account both one-halo…

Astrophysics · Physics 2009-11-11 Anze Slosar , Uros Seljak , Argyro Tasitsiomi

We statistically analyse a recent sample of data points measuring the fine-structure constant alpha (relative to the terrestrial value) in quasar absorption systems. Using different statistical techniques, we find general agreement with…

Cosmology and Nongalactic Astrophysics · Physics 2012-08-02 J. C. Berengut , E. M. Kava , V. V. Flambaum

The line-of-sight velocity dispersion profile of galaxy clusters exhibits a "kink" corresponding to the spatial extent of orbiting galaxies. Because the spatial extent of a cluster is correlated with the amplitude of the velocity dispersion…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-21 Erika L. Wagoner , Eduardo Rozo , Han Aung , Daisuke Nagai

The caustic technique uses galaxy redshifts alone to measure the escape velocity and mass profiles of galaxy clusters to clustrocentric distances well beyond the virial radius, where dynamical equilibrium does not necessarily hold. We…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Ana Laura Serra , Antonaldo Diaferio , Giuseppe Murante , Stefano Borgani

In this paper we investigate the velocity dispersion profiles of clusters of galaxies for seven cosmological models. One model is the SCDM model, and the others are six low-density models with the density parameter $\Omega=0.1$, 0.2 or 0.3…

Astrophysics · Physics 2015-06-24 Y. P. Jing , G. Boerner

We propose a simple way to estimate the parameter beta = Omega_m^(0.6)/b from three-dimensional galaxy surveys. Our method consists in measuring the relation between the cosmological velocity and gravity fields, and thus requires peculiar…

Astrophysics · Physics 2011-02-11 Stéphane Colombi , Michał Chodorowski , Romain Teyssier

The velocity field of intracluster gas in galaxy clusters contains key information on the virialization of infalling material, the dissipation of AGN energy into the surrounding medium, and the validity of the hydrostatic hypothesis. The…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-14 D. Eckert , M. Markevitch , J. A. ZuHone , M. Regamey , I. Zhuravleva , Y. Ichinohe , N. Truong , N. Okabe , D. R. Wik

The cosmic dipole observed in the cosmic microwave background (CMB) is traditionally interpreted as being caused by the observer's motion relative to the background. However, tensions with dipole measurements from radio galaxy counts…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-20 Anson Chen , Jun Zhang

Quasar emission lines are often shifted from the systemic velocity due to various dynamical and radiative processes in the line-emitting region. The level of these velocity shifts depends both on the line species and on quasar properties.…

Likelihood fitting to two-point clustering statistics made from galaxy surveys usually assumes a multivariate normal distribution for the measurements, with justification based on the central limit theorem given the large number of…

Cosmology and Nongalactic Astrophysics · Physics 2019-04-23 Mike Shengbo Wang , Will J. Percival , Santiago Avila , Robert Crittenden , Davide Bianchi

The systemic velocity or redshift of galaxies is a convenient tool to calculate their distances in the absence of primary methods, but the uncertainties on these flow distances may be substantial due to galaxy peculiar motions. Here, we…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-23 Konstantin Haubner , Federico Lelli , Enrico Di Teodoro , Francis Duey , Stacy McGaugh , James Schombert

We report on a new study of the velocity distribution in N-body simulations. We investigate the center-of-mass and internal kinetic energies of coarsening cells as a function of time, cell size and cell mass. By using self-similar…

Astrophysics · Physics 2011-05-23 Alvaro Dominguez , Adrian L. Melott

Radial velocity dispersion in spheroidal and elliptical galaxies, as a function of radial distance from the center of the galaxy, has been derived from Cosmological Special Relativity. For velocity dispersions in the outer regions of…

General Physics · Physics 2009-11-13 John G. Hartnett

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 describe an approximate statistical model for the sample variance distribution of the non-linear matter power spectrum that can be calibrated from limited numbers of simulations. Our model retains the common assumption of a multivariate…