English
Related papers

Related papers: Cosmological Velocity Bias

200 papers

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 present galaxy circular velocity functions (GCVFs) for 34 low redshift (z < 0.15) clusters identified in the Sloan Digital Sky Survey (SDSS), for fifteen clusters drawn from dark matter simulations of hierarchical structure growth in a…

Astrophysics · Physics 2008-11-26 V. Desai , J. J. Dalcanton , L. Mayer , D. Reed , T. Quinn , F. Governato

Our study is meant to extend our knowledge of the galaxy color and luminosity segregation in velocity space (VCS and VLS, resp.), to clusters at intermediate and high redshift. Our sample is a collection of 41 clusters in the 0.4<~z<~1.5…

Astrophysics of Galaxies · Physics 2016-11-02 S. Barsanti , M. Girardi , A. Biviano , S. Borgani , M. Annunziatella , M. Nonino

We study the systematic bias introduced when selecting the spectroscopic redshifts of brighter cluster galaxies to estimate the velocity dispersion of galaxy clusters from both simulated and observational galaxy catalogues. We select…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 L. Old , M. E. Gray , F. R. Pearce

We examine the peculiar velocity distribution function of galaxies in cosmological many-body gravitational clustering. Our statistical mechanical approach derives a previous basic assumption and generalizes earlier results to galaxies with…

Astrophysics · Physics 2009-11-10 Bernard Leong , William Saslaw

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

We introduce the velocity coherence scale $R_v$, the scale at which the spherical volume average of the trace of the velocity correlation tensor transitions from scaling faster than the sphere radius to scaling more slowly. This corresponds…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-09 Leonardo Giani , Cullan Howlett , Chris Blake , Ryan J. Turner , Tamara M. Davis

The use of galaxy clusters as cosmological probes hinges on our ability to measure their masses accurately and with high precision. Hydrostatic mass is one of the most common methods for estimating the masses of individual galaxy clusters,…

Cosmology and Nongalactic Astrophysics · Physics 2014-02-12 Kaylea Nelson , Erwin T. Lau , Daisuke Nagai , Douglas H. Rudd , Liang Yu

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

We present the results of a weak gravitational lensing analysis to determine whether the stellar mass or the velocity dispersion is more closely related to the amplitude of the lensing signal around galaxies - and hence to the projected…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Edo van Uitert , Henk Hoekstra , Marijn Franx , David G. Gilbank , Michael D. Gladders , H. K. C. Yee

Semi-analytical models of galaxy formation can be used to predict the evolution of the number density of early-type galaxies as a function of the circular velocity at the virial radius, v_{c,vir}. Gravitational lensing probability and…

Astrophysics · Physics 2009-11-11 Kyu-Hyun Chae , Shude Mao , Xi Kang

We want to study how the velocity segregation and the radial profile of the velocity dispersion depend on the prominence of the brightest cluster galaxies (BCGs). We divide a sample of 102 clusters and groups of galaxies into four bins of…

Astrophysics of Galaxies · Physics 2019-10-16 S. Zarattini , J. A. L. Aguerri , A. Biviano , M. Girardi , E. M. Corsini , E. D'Onghia

We derive the central stellar velocity dispersion function for quiescent galaxies in 280 massive clusters with $\log (M_{200} / M_{\odot}) > 14$ in IllustrisTNG300. The velocity dispersion function is an independent tracer of the dark…

Astrophysics of Galaxies · Physics 2024-06-03 Jubee Sohn , Margaret J. Geller , Josh Borrow , Mark Vogelsberger

We consider the process of stellar binaries tidally disrupted by a supermassive black hole. For highly eccentric orbits, as one star is ejected from the three-body system, the companion remains bound to the black hole. Hypervelocity stars…

Astrophysics of Galaxies · Physics 2015-06-16 Elena M. Rossi , Shiho Kobayashi , Re'em Sari

B,V CCD frames have been used to derive surface brightness profiles for NGC 3201 out to ~18 arcmin. A total of 857 radial velocities with median precision ~1 km/s for 399 member giants have been used to trace the velocity dispersion profile…

Astrophysics · Physics 2009-10-28 Patrick Cote , Douglas L. Welch , Philippe Fischer , K. Gebhardt

Cosmological parameters can be measured by comparing peculiar velocities with those predicted from a galaxy density field. Previous work has tested the accuracy of this approach with N-body simulations, but generally on idealised mock…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-27 Amber M. Hollinger , Michael J. Hudson

We have investigated the possibility of inferring peculiar velocities for clusters of galaxies from the Doppler shift of scattered cosmic microwave background (CMB) photons. We find that if the core radius of the gas distribution or the…

Astrophysics · Physics 2015-06-24 Martin G. Haehnelt , Max Tegmark

We report new constraints on the local escape speed of our Galaxy. Our analysis is based on a sample of high velocity stars from the RAVE survey and two previously published datasets. We use cosmological simulations of disk galaxy formation…

We present velocity statistics of galaxies and their biases inferred from the statistics of the underlying dark matter using a cosmological hydrodynamic simulation of galaxy formation in low-density and spatially flat cold dark matter…

Astrophysics · Physics 2009-11-07 Kohji Yoshikawa , Y. P. Jing , Gerhard Börner

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