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Related papers: Bulk-flow and beta_I from the SMAC project

200 papers

We present the results of a redshift survey of both cluster and intercluster galaxies in the central part of the Shapley Concentration, the richest supercluster of clusters in the nearby Universe, consisting of ~2000 radial velocities. We…

Astrophysics · Physics 2016-08-30 E. Zucca , S. Bardelli , A. Baldi , G. Zamorani , L. Moscardini , R. Scaramella

Several recent numerical simulations of off-center cluster mergers predict that significant angular momentum with associated velocities of a few x 10^{3} km/s can be imparted to the resulting cluster. Such gas bulk velocities can be…

Astrophysics · Physics 2009-11-06 Renato A. Dupke , Joel N. Bregman

The hot intracluster medium (ICM) provides a unique laboratory to test multi-scale physics in numerical simulations and probe plasma physics. Utilizing archival Chandra observations, we measure density fluctuations in the ICM in a sample of…

High Energy Astrophysical Phenomena · Physics 2024-01-30 Annie Heinrich , Irina Zhuravleva , Congyao Zhang , Eugene Churazov , William Forman , Reinout J. van Weeren

A hierarchical Bayesian model is applied to the Cosmicflows-3 catalog of galaxy distances in order to derive the peculiar velocity field and distribution of matter within $z \sim 0.054$. The model assumes the $\Lambda$CDM model within the…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-23 R. Graziani , H. M. Courtois , G. Lavaux , Y. Hoffman , R. B. Tully , Y. Copin , D. Pomarède

This article explores an update to the cosmography of the local Universe within z=0.1, incorporating galaxy peculiar velocity datasets from the first data releases of WALLABY, FAST, and DESI surveys. The galaxies with peculiar velocities…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-17 Helene M. Courtois , Jeremy Mould , Amber M. Hollinger , Alexandra Dupuy , Chuan-Peng Zhang

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 have identified 335 galaxy cluster and group candidates spanning 0<z<2, using a 4.5um selected sample of galaxies in a 7.25 deg^2 region in the Spitzer/IRAC Shallow Survey. Using full redshift probability distributions for all galaxies,…

We present analysis of local large scale flows using the Surface Brightness Fluctuation (SBF) Survey for the distances to 300 early-type galaxies. Our models of the distribution function of mean velocity and velocity dispersion at each…

Astrophysics · Physics 2010-11-04 John L. Tonry , John P. Blakeslee , Edward A. Ajhar , Alan Dressler

We estimate cluster masses and velocity dispersions for 123 clusters from optical spectroscopy to compare the Sunyaev-Zeldovich (SZ) mass proxy and dynamical masses. Our new survey, HeCS-SZ (Hectospec Cluster Survey of SZ-selected…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-16 Kenneth J. Rines , Margaret J. Geller , Antonaldo Diaferio , Ho Seong Hwang

This is the second paper in a series presenting the results from a 500 $h^{-1}$Mpc large constrained hydro-dynamical simulation of the local Universe (SLOW). The initial conditions are based on peculiar velocities derived from the…

We analyse a catalogue of simulated clusters within the theoretical framework of the Spherical Collapse Model (SCM), and demonstrate that the relation between the infall velocity of member galaxies and the cluster matter overdensity can be…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-13 Guido Cupani , Marino Mezzetti , Fabio Mardirossian

The low-order kinematic moments of galaxies, namely bulk flow and shear, enables us to test whether theoretical models can accurately describe the evolution of the mass density field in the nearby Universe. We use the so-called etaMLE…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-05 Fei Qin , Cullan Howlett , Lister Staveley-Smith , Tao Hong

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

Cosmic Flows is a program to determine galaxy distances for 30,000 galaxies with systematic errors below 2%, almost ten times the number currently known and a five-fold improvement in systematics. The resultant velocity field will provide…

Cosmology and Nongalactic Astrophysics · Physics 2012-05-22 H. M. Courtois , R. B. Tully

We present the first application of a spherical collapse model to a supercluster of galaxies. Positions and redshifts of $\sim 3000$ galaxies in the Shapley Supercluster (SSC) are used to define velocity caustics that limit the…

Astrophysics · Physics 2009-10-31 Andreas Reisenegger , H. Quintana , Eleazar R. Carrasco , Jerónimo Maze

The bulk flow is a volume average of the peculiar velocities and a useful probe of the mass distribution on large scales. The gravitational instability model views the bulk flow as a potential flow that obeys a Maxwellian Distribution. We…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-31 Abhinav Kumar , Yuyu Wang , Hume A. Feldman , Richard Watkins

We have found evidence of bulk velocities following active galactic nucleus (AGN) bubbles in the Virgo cluster and galaxy motions in the Centaurus cluster. In order to increase the sample and improve our understanding of the intracluster…

Astrophysics of Galaxies · Physics 2023-04-26 Efrain Gatuzz , J. S. Sanders , K. Dennerl , A. Liu , A. C. Fabian , C. Pinto , D. Eckert , H. Russell , T. Tamura , S. A. Walker , J. ZuHone

Galaxy cluster masses, rich with cosmological information, can be estimated from internal dark matter (DM) velocity dispersions, which in turn can be observationally inferred from satellite galaxy velocities. However, galaxies are biased…

We follow a formalism presented by Kaiser to calculate the variance of bulk flows in large scale surveys. We apply the formalism to a mock survey of Abell clusters \'a la Lauer \& Postman and find the variance in the expected bulk…

Astrophysics · Physics 2007-05-23 Hume A. Feldman , Richard Watkins

We define a large sample of galaxies for use in a study of the fundamental plane in the intermediate redshift cluster CL1358+62 at $z=0.33$. We have analyzed high resolution spectra for 55 members of the cluster. The data were acquired with…

Astrophysics · Physics 2009-10-31 Daniel D. Kelson , Garth D. Illingworth , Pieter G. van Dokkum , Marijn Franx