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Related papers: Measuring Bulk Flows in Large Scale Surveys

200 papers

To study galactic motions on the largest available scales, we require bulk flow moments whose window functions have as narrow a peak as possible and having as small an amplitude as possible outside the peak. Typically the moments found…

Astrophysics · Physics 2008-05-13 Hume A. Feldman , Michael J. Hudson , Richard Watkins

I summarize both observational and theoretical developments in the last few years in measuring and understanding the large-scale velocity field of galaxies, with special attention to the bulk flow, or average peculiar velocity, within…

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

Cooling flows, cluster mergers and motions of galaxies through the cluster gas with supersonic and sonic velocities must lead to large scale motions of the intracluster medium (ICM). A high-resolution numerical simulation of X-ray cluster…

Astrophysics · Physics 2009-11-10 Rashid A. Sunyaev , Michael L. Norman , Greg L. Bryan

We analyze in detail the peculiar velocity field traced by 56 clusters within 120 h^-1 Mpc in the Streaming Motions of Abell Clusters (SMAC) sample. The bulk flow of the SMAC sample is 687 +- 203 km/s, toward l = 260 +- 13, b = 0 +- 11. We…

Astrophysics · Physics 2009-11-10 Michael J. Hudson , Russell J. Smith , John R. Lucey , Enzo Branchini

Bulk flow velocities are typically estimated in the idealised picture where observers are moving within a perfectly homogeneous and isotropic space-time. This picture is consistent within standard perturbation theory up to relativistic…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-22 Asta Heinesen

Analysis of the Pangu N-body simulation validates that the bulk flow of halos follows a Maxwellian distribution which variance is consistent with the prediction of the linear theory of structure formation. We propose that the consistency…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Ming Li , Jun Pan , Liang Gao , Yipeng Jing , Xiaohu Yang , Xuebin Chi , Longlong Feng , Xi Kang , Weipeng Lin , Guihua Shan , Long Wang , Donghai Zhao , Pengjie Zhang

I address the following issues: All bulk velocity measurements (but one) are consistent with our standard gravitational instability theory. New accurate data and reconstruction methods allow high-resolution dynamical analysis nearby,…

Astrophysics · Physics 2007-05-23 Avishai Dekel

We present a simple method for measuring cosmological bulk flows from large redshift surveys, based on the apparent dimming or brightening of galaxies due to their peculiar motion. It is aimed at estimating bulk flows of cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Adi Nusser , Enzo Branchini , Marc Davis

For over a decade there have been contradictory claims in the literature about whether the local bulk flow motion of galaxies is consistent or in tension with the $\Lambda$CDM model. While it has become evident that systematics affect bulk…

Cosmology and Nongalactic Astrophysics · Physics 2023-10-27 A. M. Whitford , C. Howlett , T. M. Davis

We present an analysis comparing the bulk--flow measurements for six recent peculiar velocity surveys, namely, ENEAR, SFI, RFGC, SBF and the Mark III singles and group catalogs. We study whether the direction of the bulk--flow estimates are…

Astrophysics · Physics 2009-03-19 Devdeep Sarkar , Hume A. Feldman , Richard Watkins

Using a dynamical 3-D reconstruction procedure we estimate the peculiar velocities of $R\ge0$ Abell/ACO galaxy clusters from their measured redshift within 25000 km/sec. The reconstruction algorithm relies on the linear gravitational…

Astrophysics · Physics 2009-10-28 Enzo Branchini , Manolis Plionis , Dennis W. Sciama

In this chapter we review observations and techniques for measuring both bulk flows in prominences and prominence mass. Measuring these quantities is essential to development and testing of models discussed throughout this book. Prominence…

Solar and Stellar Astrophysics · Physics 2015-02-04 T. A. Kucera

Full sky surveys of peculiar velocity are arguably the best way to map the large scale structure out to distances of a few times 100 Mpc/h. Using the largest and most accurate ever catalog of galaxy peculiar velocities "Cosmicflows-2", the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-24 Yehuda Hoffman , Helene M. Courtois , R. Brent Tully

We investigate the power spectrum of velocity fluctuations in the universe, $V^2(k)$, starting from four different measures of velocity: (1) the power spectrum of velocity fluctuations from peculiar velocities of galaxies; (2) the rms…

Astrophysics · Physics 2009-10-30 M. Gramann

The low order moments, such as the bulk flow and shear, of the large scale peculiar velocity field are sensitive probes of the matter density fluctuations on very large scales. In practice, however, peculiar velocity surveys are usually…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-15 Hume A. Feldman , Richard Watkins , Michael J. Hudson

The peculiar radial velocities of eight clusters of galaxies, as determined from a variety of distance indicators, are consistent with a bulk flow not greatly different in direction and magnitude from the velocity vector of the Local Group…

Astrophysics · Physics 2007-05-23 Donald H. Gudehus

What is the role of clusters of galaxies in probing the large-scale velocity field of the universe? We investigate the distribution of peculiar velocities of clusters of galaxies in the popular low-density ($\Omega=0.3$) flat…

Astrophysics · Physics 2009-10-22 Neta A. Bahcall , Renyue Cen , Mirt Gramann

We present an improved Minimal Variance (MV) method for using a radial peculiar velocity sample to estimate the average of the three-dimensional velocity field over a spherical volume, which leads to an easily interpretable bulk flow…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-29 Sarah Peery , Richard Watkins , Hume A. Feldman

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

The SMAC project is a Fundamental Plane peculiar velocity survey of 56 clusters of galaxies to a depth of cz ~ 12000 km/s. We present here some results from the analysis of the SMAC velocity field, focussing on three specific features: the…