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Related papers: Kriging Interpolating Cosmic Velocity Field

200 papers

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

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

Kriging based on Gaussian random fields is widely used in reconstructing unknown functions. The kriging method has pointwise predictive distributions which are computationally simple. However, in many applications one would like to predict…

Statistics Theory · Mathematics 2019-03-20 Wenjia Wang , Rui Tuo , C. F. Jeff Wu

We have used the Optical Redshift Survey (ORS; Santiago et al. 1995) to construct the gravity field due to fluctuations in the galaxy density field out to distances of 8000 km/s. At large scales where linear theory applies, the comparison…

We propose a method for deriving a dynamical lower bound on $\Omega$ from diverging flows in low-density regions, based on the fact that large outflows are not expected in a low-$\Omega$ universe. The velocities are assumed to be induced by…

Astrophysics · Physics 2009-10-22 Avishai Dekel , Martin Rees

We present an alternative, Bayesian method for large-scale reconstruction from observed peculiar velocity data. The method stresses a rigorous treatment of the random errors and it allows extrapolation into poorly sampled regions in real…

Astrophysics · Physics 2009-10-31 Saleem Zaroubi , Yehuda Hoffman , Avishai Dekel

The evolution of galaxy cluster counts is a powerful probe of several fundamental cosmological parameters. A number of recent studies using this probe have claimed tension with the cosmology preferred by the analysis of the Planck primary…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-21 C. E. Caldwell , I. G. McCarthy , I. K. Baldry , C. A. Collins , J. Schaye , S. Bird

We analyse the large--scale velocity field obtained by N--body simulations of cold dark matter (CDM) models with non--Gaussian primordial density fluctuations, considering models with both positive and negative primordial skewness in the…

Astrophysics · Physics 2015-06-24 F. Lucchin , S. Matarrese , A. Messina , L. Moscardini , G. Tormen

The dynamics of the intracluster medium (ICM) is affected by turbulence driven by several processes, such as mergers, accretion and feedback from active galactic nuclei. X-ray surface brightness fluctuations have been used to constrain…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-14 Marco Simonte , Franco Vazza , Fabrizio Brighenti , Marcus Brueggen , Tom W. Jones

We describe a new method of overcoming problems inherent in peculiar velocity surveys by using data compression as a filter with which to separate large-scale, linear flows from small-scale noise that biases the results systematically. We…

Astrophysics · Physics 2007-05-23 Hume A Feldman , Richard Watkins , Adrian Melott , Will Chambers

Galaxy peculiar velocities can be used to trace the growth of structure on cosmological scales. In the radial direction, peculiar velocities cause redshift space distortions, an established cosmological probe, and can be measured…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-06 Iain Duncan , David Alonso , Anže Slosar , Kate Storey-Fisher

Observed accretion rates onto the Milky-Way and other local spirals fall short of that required to sustain star formation for cosmological timescales. A potential avenue for this unseen accretion is an inflow in the volume-filling hot phase…

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 an estimate of the bulk flow in a volume of radii $150-200h^{-1}$Mpc using the minimum variance (MV) method with data from the CosmicFlows-4 (CF4) catalog. The addition of new data in the CF4 has resulted in an increase in the…

This paper combines observational datasets and cosmological simulations to generate realistic numerical replicas of the nearby Universe. These latter are excellent laboratories for studies of the non-linear process of structure formation in…

Peculiar velocity surveys, which measure galaxy peculiar velocities directly from standard candles in addition to redshifts, can provide strong constraints on the linear growth rate of cosmological large-scale structure at low redshift. The…

The kinematics of galaxies with 10 megaparsecs (10 Mpc) of the Milky Way is investigated using published distances and radial velocities. With respect to the average Hubble flow (isotropic or simple anisotropic), there is NO systematic…

Astrophysics · Physics 2009-11-07 Alan B. Whiting

We propose a new strategy to probe the power spectrum on large scales using galaxy peculiar velocities. We explore the properties of surveys that cover only two small fields in opposing directions on the sky. Surveys of this type have…

Astrophysics · Physics 2009-10-30 Hume A. Feldman , Richard Watkins

We present an improved framework for estimating the growth rate of large-scale structure, using measurements of the galaxy-velocity cross-correlation in configuration space. We consider standard estimators of the velocity auto-correlation…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-03 Ryan J. Turner , Chris Blake , Rossana Ruggeri

In previous works we proposed the Reverse Zeldovich Approximation (RZA) method, which can be used to estimate the cosmological initial conditions underlying the galaxy distribution in the Local Universe using peculiar velocity data. In this…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Timur Doumler , Stefan Gottloeber , Yehuda Hoffman , Helene Courtois