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相关论文: Pairwise Velocities of Dark Matter Halos: a Test f…

200 篇论文

We analyzed the statistics of subhalo abundance of galaxy-sized and giant-galaxy-sized halos formed in a high-resolution cosmological simulation of a 46.5Mpc cube with the uniform mass resolution of $10^6 M_{\odot}$. We analyzed all halos…

天体物理学 · 物理学 2014-11-18 Tomoaki Ishiyama , Toshiyuki Fukushige , Junichiro Makino

(Shortened) We use N-body simulations to investigate the structure and dynamical evolution of dark matter halos in galaxy clusters. Our sample consists of nine massive halos from an EdS universe with scale free power spectrum and n = -1.…

天体物理学 · 物理学 2015-06-24 Giuseppe Tormen , Francois R. Bouchet , Simon D. M. White

The velocity correlation functions directly measured from the peculiar velocity field of dark matter in numerical simulations are known to have an amplitude lower than that predicted by theoretical models at large scales. The trend persists…

宇宙学与河外天体物理 · 物理学 2026-02-05 Yao-Tsung Chuang , Teppei Okumura , Takahiro Nishimichi

In this work I investigate the statistical properties of a huge catalog of closely interacting pairs of dark matter haloes, extracted from the Millennium Simulation database. Only haloes that reach a minimum mass greater than 8.6 \times…

宇宙学与河外天体物理 · 物理学 2011-12-02 Jorge Moreno

$N$-body cosmological simulations are an essential tool to understand the observed distribution of galaxies. We use the MultiDark simulation suite, run with the Planck cosmological parameters, to revisit the mass and velocity functions. At…

宇宙学与河外天体物理 · 物理学 2017-05-16 Johan Comparat , Francisco Prada , Gustavo Yepes , Anatoly Klypin

We use the recently completed one billion particle Via Lactea II LambdaCDM simulation to investigate local properties like density, mean velocity, velocity dispersion, anisotropy, orientation and shape of the velocity dispersion ellipsoid,…

We study the formation and evolution of the dark matter halos in a LCDM model. The dynamics of 16.8 million DM particles is followed numerically in a box of 60 Mpc/h with the dynamic range of 32,000 in spatial resolution. The high…

天体物理学 · 物理学 2007-05-23 S. Gottloeber , A. A. Klypin , A. V. Kravtsov

We study the formation of dark matter halos in the concordance LCDM model over a wide range of redshifts, from z=20 to the present. Our primary focus is the halo mass function, a key probe of cosmology. By performing a large suite of…

天体物理学 · 物理学 2008-11-26 Zarija Lukic , Katrin Heitmann , Salman Habib , Sergei Bashinsky , Paul M. Ricker

We present distribution functions and spatial correlations of the shapes of dark matter halos derived from Hubble Volume simulations of a LambdaCDM universe. We measure both position and velocity shapes within spheres encompassing mean…

天体物理学 · 物理学 2008-11-26 S. F. Kasun , A. E. Evrard

It has long been regarded as difficult for a cosmological model to account simultaneously for the galaxy luminosity, mass, and velocity distributions. We revisit this issue using a modern compilation of observational data along with the…

宇宙学与河外天体物理 · 物理学 2015-05-18 Sebastian Trujillo-Gomez , Anatoly Klypin , Joel Primack , Aaron J. Romanowsky

We investigate the evolution in the dark matter halo circular velocity function, measured at a fixed physical radius of 20 kpc (v_20), which is likely to be a good proxy for galaxy circular velocity, in the Millennium-II simulation. We find…

宇宙学与河外天体物理 · 物理学 2015-06-12 Simone M. Weinmann , Marijn Franx , Pieter van Dokkum , Rachel Bezanson

Shock waves driven in the intergalactic medium during the merging of galaxy clusters have been observed in X-ray imaging and spectroscopy. Fluid motions inferred from the shock strength and morphology can be compared to the cold dark matter…

天体物理学 · 物理学 2009-11-13 Milos Milosavljevic , Jun Koda , Daisuke Nagai , Ehud Nakar , Paul R. Shapiro

Using a set of $\pppm$ simulation which accurately treats the density evolution of two components of dark matter, we study the evolution of clusters in the Cold + Hot dark matter (CHDM) model. The mass function, the velocity dispersion…

天体物理学 · 物理学 2009-10-22 Y. P. Jing , L. Z. Fang

We used 87 high resolution hydrodynamical cosmological simulations from the NIHAO suite to investigate the relation between the maximum circular velocity (Vmax) of a dark matter halo in a collisionless simulation and the velocity width of…

星系天体物理 · 物理学 2016-09-21 Andrea V. Macciò , Silviu M. Udrescu , Aaron A. Dutton , Aura Obreja , Liang Wang , Greg R. Stinson , Xi Kang

We investigate the internal structure of cold dark matter halos using high resolution N-body simulations. As the mass and force resolution are increased, halo density profiles become steeper, asymptoting to a slope of $\sim -4/3$ in the…

天体物理学 · 物理学 2007-05-23 Ben Moore , Sebastiano Ghigna , Fabio Governato , George Lake , Tom Quinn , Joachim Stadel

Much evidence suggests that we live in a flat Cold Dark Matter universe with a cosmological constant. Accurate analytic formulae are now available for many properties of the dark halo population in such a Universe. Assuming current…

天体物理学 · 物理学 2009-07-09 H. J. Mo , S. D. M. White

High-resolution LCDM cosmological N-body simulations are used to study the properties of galaxy-size dark halos in different environments (cluster, void, and "field"). Halos in clusters and their surroundings have a median spin parameter…

天体物理学 · 物理学 2009-11-13 V. Avila-Reese , P. Colin , S. Gottloeber , C. Firmani , C. Maulbetsch

A long-standing issue in peculiar velocity cosmology is whether the halo/galaxy velocity bias $b_v=1$ at large scale. The resolution of this important issue must resort to high precision cosmological simulations. However, this is hampered…

宇宙学与河外天体物理 · 物理学 2018-07-04 Junde Chen , Pengjie Zhang , Yi Zheng , Yu Yu , Yipeng Jing

The merging galaxy cluster 1E 0657-56, known as the "bullet cluster," is one of the hottest clusters known. The X-ray emitting plasma exhibits bow-shock-like temperature and density jumps. The segregation of this plasma from the peaks of…

天体物理学 · 物理学 2008-03-13 Jun Koda , Milos Milosavljevic , Paul R. Shapiro , Daisuke Nagai , Ehud Nakar

N-body simulations were conducted of pairs of galaxies with a 3:1 mass ratio on parabolic orbits, in order to quantify the effect of dynamical friction. The effects of varying the ratio of the dark matter halo size to the distance of…

天体物理学 · 物理学 2016-08-30 Roger E. Bartlett , Jane C. Charlton