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

200 papers

We present ROSAT HRI data of the distant and X-ray luminous (L_x(bol)=2.6^ {+0.4}_{-0.2} 10^{45}erg/sec) cluster of galaxies 3C 295. We fit both a one-dimensional and a two-dimensional isothermal beta-model to the data, the latter one…

Astrophysics · Physics 2009-10-31 D. M. Neumann

We analyze the origin of the large-scale bulk flow using the CosmicFlows-4 (CF4) peculiar-velocity catalog. We decompose the observed motions into internal components, generated by mass fluctuations within 200 Mpc/h, and external ones…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-29 Richard Watkins , Hume A. Feldman

A theoretical model framework of spherical symmetry is presented for a composite astrophysical system of two polytropic fluids coupled together by gravity to explore large-scale shocks and flow dynamics in clusters of galaxies or in…

Astrophysics · Physics 2009-11-13 Yu-Qing Lou , Yan-Fei Jiang , Chi-Chuan Jin

The hot plasma in galaxy clusters, the intracluster medium (ICM), is expected to be shaped by subsonic turbulent motions, which are key for heating, cooling, and transport mechanisms. The turbulent motions contribute to the non-thermal…

We use the Cluster-EAGLE simulations to explore the velocity bias introduced when using galaxies, rather than dark matter particles, to estimate the velocity dispersion of a galaxy cluster, a property known to be tightly correlated with…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-27 Thomas Joshua Armitage , David. J. Barnes , Scott. T. Kay , Yannick M. Bahé , Claudio Dalla Vecchia , Robert A. Crain , Tom Theuns

We used the FourStar near-IR camera on Magellan-Baade to obtain high S/N H-Band imaging of 66 galaxies with radial velocities of 2000 < V < 5000 km/s. Our goal was to use the superior distance measurements of surface-brightness-fluctuations…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-11 Alan Dressler , Andrew Monson

We compare the peculiar velocity field within 65 $h^{-1}$ Mpc predicted from 2MASS photometry and public redshift data to three independent peculiar velocity surveys based on type Ia supernovae, surface brightness fluctuations in…

Astrophysics · Physics 2007-05-23 R. W. Pike , Michael J. Hudson

The fluctuations in the Cosmic Microwave Background (CMB) intensity due to the Sunyaev-Zeldovich (SZ) effect are the sum of a thermal and a kinetic contribution. Separating the two components to measure the peculiar velocity of galaxy…

We present velocities of galactic outflows in seven star-forming galaxies at $z=$5-6 with stellar masses of $M_* \sim10^{10.1}\ \rm{M_\odot}$. Although it is challenging to observationally determine the outflow velocities, we overcome this…

Astrophysics of Galaxies · Physics 2019-12-18 Yuma Sugahara , Masami Ouchi , Yuichi Harikane , Nicolas Bouché , Peter D. Mitchell , Jérémy Blaizot

We aim to settle the debate regarding the fraction of the Local Group's peculiar velocity that is induced by structures beyond the Great Attractor by calculating the dipole anisotropy of the largest, all-sky, truly X-ray selected cluster…

Astrophysics · Physics 2009-11-13 Dale D. Kocevski , Harald Ebeling

We study the kinematics of the interstellar medium (ISM) viewed "down the barrel" in 20 gravitationally lensed galaxies during Cosmic Noon ($z=1.5 - 3.5$). We use moderate-resolution spectra ($R\sim4000$) from Keck/ESI and Magellan/MagE to…

A formalism that simultaneously searches for the monopolar and dipolar peculiar velocities is presented. The formalism is applied to (1) the Mark III catalogue, (2) Lauer and Postman's Abell cluster catalogue, and (3) Riess et al.'s Type Ia…

Astrophysics · Physics 2009-10-28 Xiangdong Shi

We have identified 335 galaxy cluster and group candidates, 106 of which are at z > 1, using a 4.5 um selected sample of objects from a 7.25 deg^2 region in the Spitzer Infrared Array Camera (IRAC) Shallow Survey. Clusters were identified…

Reviews observational situation in the measurement of peculiar velocities in the local universe. Emphasis is placed on such topics as: Do spirals and ellipticals yield the same peculiar velocity field? What is the cluster velocity…

Astrophysics · Physics 2007-05-23 Riccardo Giovanelli

The distributions of peculiar velocities of rich clusters and of groups of galaxies are investigated for different cosmological models and are compared with observations. Four cosmological models are studied: standard ($\Omega=1$) CDM,…

Astrophysics · Physics 2007-05-23 Neta A. Bahcall , Mirt Gramann , Renyue Cen

An extensive redshift survey has been conducted on a sample of 15 nearby (0.01 < z < 0.05) clusters of galaxies. A total number of 860 redshifts were determined by fitting of emission--lines and/or cross-correlation techniques. Of this…

Astrophysics · Physics 2007-05-23 P. Stein

The mounting evidence for anomalously large peculiar velocities in our Universe presents a challenge for the LCDM paradigm. The recent estimates of the large scale bulk flow by Watkins et al. are inconsistent at the nearly 3 sigma level…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Mark Wyman , Justin Khoury

We present Tully-Fisher observations for 35 rich Abell clusters of galaxies. Results from I band photometry and optical rotation curve work comprise the bulk of this paper. This is the third such data installment of an all-sky survey of 52…

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

We are engaged in an investigation of the relationship between the properties of BCG candidates and X-ray characteristics of their host clusters for a flux-limited sample of ~250 ACO clusters from the ROSAT all-sky survey. We aim to search…

Astrophysics · Physics 2007-05-23 P. D. Lynam , C. A. Collins , P. A. James , H. Boehringer , D. M. Neumann