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Related papers: Velocity bias in a LCDM model

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We use numerical simulations of critically-closed cold dark matter (CDM) models to study the effects of numerical resolution on observable quantities. We study simulations with up to $256^3$ particles using the particle-mesh (PM) method and…

Astrophysics · Physics 2009-10-22 James M. Gelb , Edmund Bertschinger

The increasing sensitivity of current experiments, which nowadays routinely measure the thermal SZ effect within galaxy clusters, provide the hope that peculiar velocities of individual clusters of galaxies will be measured rather soon…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Klaus Dolag , Rashid Sunyaev

We present the first results from the new Bolshoi N-body cosmological LCDM simulation that uses cosmological parameters favored by current observations. The Bolshoi simulation was done in a volume 250Mpc on a side using 8billion particles…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 A. Klypin , S. Trujillo-Gomez , J. Primack

In this work we investigate the link between galaxy velocity dispersion, mass and other properties (color, morphology) with the properties of dark matter halos by comparing the clustering of galaxies at both fixed mass and velocity…

Cosmology and Nongalactic Astrophysics · Physics 2012-01-11 David A. Wake , Marijn Franx , Pieter G. van Dokkum

We use the high-resolution Aquarius cosmological dark matter simulations coupled to the semi-analytic model by Starkenburg et al. (2013) to study the HI content and velocity width properties of field galaxies at the low mass end in the…

Astrophysics of Galaxies · Physics 2016-02-17 C. Y. Yaryura , A. Helmi , M. G. Abadi , E. Starkenburg

It is a well-known fact that the gravitational effect of dark matter in galaxies is only noticeable when the orbital accelerations drop below $a_0 \simeq 2\times 10^{-8}$ cm s$^{-1}$ (Milgrom's Law). This peculiarity of the dynamic…

Cosmology and Nongalactic Astrophysics · Physics 2011-11-08 L. Acedo

We conduct a study of the gas kinematics of two quasar host galaxies at $z\gtrsim6$ traced by the [CII] emission line using ALMA. By combining deep observations at both low and high resolution, we recover the diffuse emission, resolve its…

The multicomponent dark matter model with self-scattering and inter-conversions of species into one another is an alternative dark matter paradigm that is capable of resolving the long-standing problems of $\Lambda$CDM cosmology at small…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-19 Keita Todoroki , Mikhail V. Medvedev

We investigate the relationship between a dark matter halo's mass profile and measures of the velocity dispersion of kinematic tracers within its gravitational potential. By predicting the scaling relation of the halo mass with the aperture…

Astrophysics of Galaxies · Physics 2024-03-13 Andrew Sullivan , Chris Power , Connor Bottrell

Using high-resolution simulations within the Cold and Warm Dark Matter models we study the evolution of small scale structure in the Local Volume, a sphere of 8 Mpc radius around the Local Group. We compare the observed spectrum of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 A. V. Tikhonov , S. Gottloeber , G. Yepes , Y. Hoffman

We present the first galaxy-galaxy weak lensing results using early data from the Canada-France-Hawaii Telescope Legacy Survey (CFHTLS). These results are based on ~22 sq. deg. of i' data. From this data, we estimate the average velocity…

We investigate the properties of the pairwise velocity dispersion as a function of galaxy luminosity in the context of a halo model. We derive the distribution of velocities of pairs at a given separation taking into account both one-halo…

Astrophysics · Physics 2009-11-11 Anze Slosar , Uros Seljak , Argyro Tasitsiomi

The mass of the dark matter halo of the Milky Way can be estimated by fitting analytical models to the phase-space distribution of dynamical tracers. We test this approach using realistic mock stellar halos constructed from the Aquarius…

Astrophysics of Galaxies · Physics 2015-10-28 Wenting Wang , Jiaxin Han , Andrew P. Cooper , Shaun Cole , Carlos Frenk , Ben Lowing

In the far future of an accelerating LCDM cosmology, the cosmic web of large-scale structure consists of a set of increasingly isolated halos in dynamical equilibrium. We examine the approach of collisionless dark matter to hydrostatic…

Astrophysics · Physics 2011-05-12 Michael T. Busha , August E. Evrard , Fred C. Adams , Risa H. Wechsler

Satellite galaxies are commonly used as tracers to measure the line-of-sight velocity dispersion ($\sigma_{\rm LOS}$) of the dark matter halo associated with their central galaxy, and thereby to estimate the halo's mass. Recent…

Astrophysics of Galaxies · Physics 2018-03-06 Pascal J. Elahi , Chris Power , Claudia del P. Lagos , Rhys Poulton , Aaron S. G. Robotham

We study velocity moments of elliptical galaxies in the Coma cluster using Jeans equations. The dark matter distribution in the cluster is modelled by a generalised formula based upon the results of cosmological N-body simulations. Its…

Astrophysics · Physics 2009-09-29 Ewa L. Lokas , Gary A. Mamon

We present a set of N-body simulations of a class of models in which an unstable dark matter particle decays into a stable non-interacting dark matter particle, with decay lifetime comparable to the Hubble time. We study the effects of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Mei-Yu Wang , Annika H. G. Peter , Louis E. Strigari , Andrew R. Zentner , Bryan Arant , Shea Garrison-Kimmel , Miguel Rocha

The velocity field of dark matter and galaxies reflects the continued action of gravity throughout cosmic history. We show that the low-order moments of the pairwise velocity distribution, $v_{12}$, are a powerful diagnostic of the laws of…

Cosmology and Nongalactic Astrophysics · Physics 2014-06-11 Wojciech A. Hellwing , Alexandre Barreira , Carlos S. Frenk , Baojiu Li , Shaun Cole

Using an analytic model calibrated against numerical simulations, we calculate the central densities of dark matter halos in a ``conventional'' cold dark matter model with a cosmological constant (LCDM) and in a ``tilted'' model (TLCDM)…

Astrophysics · Physics 2007-05-23 S. M. Khairul Alam , James S. Bullock , David H. Weinberg

Based on results from cold dark matter N-body simulations we develop a dynamical model for the evolution of subhaloes within host haloes of galaxy groups. Only subhaloes more massive than 5 times 10^8 M_{sol} at the time of accretion are…

Astrophysics · Physics 2008-11-26 Andreas Faltenbacher , William G. Mathews