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Related papers: Cosmic Flows: A Status Report

200 papers

This paper presents an analysis of the local peculiar velocity field based on the Wiener Filter reconstruction method. We used our currently available catalog of distance measurements containing 1,797 galaxies within 3000 km/s:…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Helene M. Courtois , Yehuda Hoffman , R. Brent Tully , Stefan Gottlober

Analyses of peculiar velocity surveys face several challenges, including low signal--to--noise in individual velocity measurements and the presence of small--scale, nonlinear flows. I will present three new analyses that attempt to address…

Astrophysics · Physics 2007-05-23 Hume A Feldman

We present a self-consistent nonparametric model of the cosmic velocity field based on the spatial distribution of IRAS galaxies in the recently completed all-sky PSC$z$ redshift survey. The most streaking feature of the PSCz model velocity…

Maximum Likelihood estimation of the bulk flow from radial peculiar motions of galaxies, generally assumes a constant velocity field inside the survey volume. The assumption is inconsistent with the definition of the bulk flow as the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Adi Nusser

This introductory talk to the 1999 Victoria Conference on Large-Scale Flows will present the ``big questions'' which will be discussed in the conference: (a) Does the velocity field converge on the largest scales? (b) Why can't we agree on…

Astrophysics · Physics 2007-05-23 Michael A. Strauss

We report on results of recent, high resolution hydrodynamic simulations of the formation and evolution of X-ray clusters of galaxies carried out within a cosmological framework. We employ the highly accurate piecewise parabolic method…

Astrophysics · Physics 2009-10-30 Michael L. Norman , Greg L. Bryan

We give the first determination of the observed peculiar velocity distribution function for a representative sample of galaxies (within 50 Mpc (H=100) of the Local Group), which includes a wide range of clustering properties. We explore in…

Astrophysics · Physics 2009-10-28 Somak Raychaudhury , William C. Saslaw

We investigate the feasibility of carrying out likelihood analysis on the velocities of galaxy clusters to determine power spectrum parameters. Using N-body simulations of cosmological density fields we show that the velocity field traced…

Astrophysics · Physics 2007-05-23 Rupert Croft , George Efstathiou

CONTENTS: 1. INTRODUCTION 2. GRAVITATIONAL INSTABILITY 3. MEASURING PECULIAR VELOCITIES 4. ANALYSIS OF OBSERVED PECULIAR VELOCITIES 5. PREDICTED MOTIONS FROM THE GALAXY DISTRIBUTION 6. TESTING BASIC HYPOTHESES 7. THE INITIAL FLUCTUATIONS 8.…

Astrophysics · Physics 2009-10-22 Avishai Dekel

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

Cosmological linear perturbation theory predicts that the peculiar velocity $V(x)$ and the matter overdensity $\delta(x)$ at a same point $x$ are statistically independent quantities, as log as the initial density fluctuations are random…

Astrophysics · Physics 2009-10-31 Naoki Seto

We present a method for decomposing the cosmological velocity field in a given volume into its divergent component due to the density fluctuations inside the volume, and its tidal component due to the matter distribution outside the volume.…

Astrophysics · Physics 2007-05-23 Y. Hoffman , A. Eldar , S. Zaroubi , A. Dekel

Cosmicflows-2 is a compilation of distances and peculiar velocities for over 8000 galaxies. Numerically the largest contributions come from the luminosity-linewidth correlation for spirals, the TFR, and the related Fundamental Plane…

Turbulence is a crucial component of dynamics of astrophysical fluids dynamics, including those of ISM, clusters of galaxies and circumstellar regions. Doppler shifted spectral lines provide a unique source of information on turbulent…

Astrophysics · Physics 2016-01-27 A. Lazarian

We consider large-scale collective motion of flat edge-on spiral galaxies from the Revised Flat Galaxy Catalogue (RFGC) taking into account the curvature of space-time in the Local Universe at the scale 100 Mpc/h. We analyse how the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Serge Parnovsky , Aleksei Parnowski

It has been recently claimed that there is no correlation between the distribution of galaxies and their peculiar velocities within the Local Volume (LV), namely a sphere of R=7/h Mpc around the Local Group (LG). It has been then stated…

Astrophysics · Physics 2009-06-23 Luis A. Martinez-Vaquero , Gustavo Yepes , Yehuda Hoffman

We present here a new parameterization for the bulk motions of galaxies and clusters (in the linear regime) that can be measured statistically from the shape and amplitude of the two-dimensional two-point correlation function. We further…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Yong-Seon Song , Cristiano G. Sabiu , Robert C. Nichol , Christopher J. Miller

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 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

Large scale flows have been a challenging feature of cosmography ever since galaxy scaling relations came on the scene 40 years ago. The next generation of surveys will offer a serious test of the standard cosmology.

Cosmology and Nongalactic Astrophysics · Physics 2017-01-25 Jeremy Mould