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相关论文: Bulk Motions in Large-Scale Void Models

200 篇论文

The hydrodynamics of bubble columns in the heterogeneous regime is investigated from experiments with bubbles at large particle Reynolds numbers and without coalescence. The void fraction field $\varepsilon$ at small scales, analyzed with…

流体动力学 · 物理学 2023-05-31 Y. Mezui , M. Obligado , A. Cartellier

We investigate the mass-velocity dispersion relation (MVDR) in 29 galaxy clusters in the HIghest X-ray FLUx Galaxy Cluster Sample (HIFLUGCS). We measure the spatially resolved, line-of-sight velocity dispersion profiles of these clusters,…

星系天体物理 · 物理学 2021-03-31 Yong Tian , Po-Chieh Yu , Pengfei Li , Stacy S. McGaugh , Chung-Ming Ko

The Hubble constant $H_0$, the current expansion rate of the universe, is one of the most important parameters in cosmology. The cosmic expansion regulates the mutually approaching motion of a pair of celestial objects due to their gravity.…

宇宙学与河外天体物理 · 物理学 2024-12-30 Wangzheng Zhang , Ming-chung Chu , Shihong Liao , Shek Yeung , Hui-Jie Hu

The discrepancy between the amplitudes of matter fluctuations inferred from Sunyaev-Zel'dovich (SZ) cluster number counts, the primary temperature, and the polarization anisotropies of the cosmic microwave background (CMB) measured by the…

宇宙学与河外天体物理 · 物理学 2016-02-03 Kiyotomo Ichiki , Chul-Moon Yoo , Masamune Oguri

We study the luminosity function, the peculiar velocities, and the sizes of voids in the Local Volume (LV) in observational samples of galaxies which contain galaxies down to MB=-10-12 within the distance 4-8Mpc. Comparing the results with…

天体物理学 · 物理学 2009-11-13 A. Tikhonov , A. Klypin

We explore the detectability of bulk motions in the X-ray emitting intracluster medium (ICM) using a catalog of 1,836 mock Astro-E2 observations of simulated clusters of galaxies. We generate high resolution mock spectra for two observing…

天体物理学 · 物理学 2009-11-10 Andrew Pawl , August E. Evrard , Renato A. Dupke

The circular velocity function (CVF) of galaxies is a fundamental test of the $\Lambda$ Cold Dark Matter (CDM) paradigm as it traces the variation of galaxy number densities with circular velocity ($v_{\rm{circ}}$), a proxy for dynamical…

星系天体物理 · 物理学 2024-09-11 Andrei Ristea , Luca Cortese , Brent Groves , A. Fraser-McKelvie , Danail Obreschkow , Karl Glazebrook

In this paper we investigate how observational effects could possibly bias cosmological inferences from peculiar velocity measurements. Specifically, we look at how bulk flow measurements are compared with theoretical predictions. Usually…

宇宙学与河外天体物理 · 物理学 2016-09-15 Per Andersen , Tamara M. Davis , Cullan Howlett

A beginning end-point for galaxy motions within the 10-Mpc Local Volume is constructed by requiring a smooth distribution of (luminous) mass at the time of recombination, which is shown to be equivalent to a smooth Hubble flow at early…

天体物理学 · 物理学 2008-11-26 Alan B. Whiting

Current measurements of the Hubble constant $H_0$ on scale less than $\sim100$ Mpc appear to be controversial, while the observations made at high redshift seem to provide a relatively low value. On the other hand, the Hubble expansion is…

天体物理学 · 物理学 2009-10-28 Xiang-Ping Wu , Bo Qin , Li-Zhi Fang

We present an improved Minimal Variance (MV) method for using a radial peculiar velocity sample to estimate the average of the three-dimensional velocity field over a spherical volume, which leads to an easily interpretable bulk flow…

宇宙学与河外天体物理 · 物理学 2018-08-29 Sarah Peery , Richard Watkins , Hume A. Feldman

The problem of the physical nature of the Hubble flow in the Local Volume ($D < 10$ Mpc) stated by Sandage(1986, 1999) is studied. New observational data on galaxy motions and matter distribution around the Local Group and nearby similar…

天体物理学 · 物理学 2007-05-23 Igor D. Karachentsev , Arthur D. Chernin , Pekka Teerikorpi

To determine the relative distances and peculiar velocities of 140 groups and clusters of galaxies at low redshifts ($z$ < 0.12), we used the fundamental plane (FP) of early-type galaxies (from the Sloan Digital Sky Survey (SDSS) data). We…

宇宙学与河外天体物理 · 物理学 2024-09-26 Flera G. Kopylova , Alexander I. Kopylov

We derive an observational constraint on a spherical inhomogeneity of the void centered at our position from the angular power spectrum of the cosmic microwave background(CMB) and local measurements of the Hubble parameter. The late time…

宇宙学与河外天体物理 · 物理学 2018-04-04 Masato Tokutake , Kiyotomo Ichiki , Chul-Moon Yoo

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…

天体物理学 · 物理学 2009-10-28 Xiangdong Shi

A surprisingly large number of galaxies with masses of $\sim10^9-10^{10}M_\odot$ at redshifts of $z\geq9$ are discovered with the James Webb Space Telescope. A possible explanation for the increase in the mass function can be the presence…

星系天体物理 · 物理学 2024-09-11 Yu. N. Eroshenko , V. N. Lukash , E. V. Mikheeva , S. V. Pilipenko , M. V. Tkachev

The formation of large voids in the Cosmic Web from the initial adiabatic cosmological perturbations of space-time metric, density and velocity of matter is investigated in cosmological model with the dynamical dark energy accelerating…

宇宙学与河外天体物理 · 物理学 2017-04-04 B. Novosyadlyj , M. Tsizh

We give a summary of our recent studies of spatial and velocity biases of galaxy-size halos in cosmological models. Recent progress in numerical techniques made it possible to simulate halos in large volumes with a such accuracy that halos…

天体物理学 · 物理学 2007-05-23 Anatoly Klypin , Andrey V. Kravtsov , Pedro Colin

We investigate the dynamics of an homogenous distribution of galaxies moving under the cosmological expansion through Euler-Poisson equations system. The solutions are interpreted with the aim of understanding the cosmic velocity fields in…

广义相对论与量子宇宙学 · 物理学 2009-11-11 Henri-Hugues Fliche , Jean-Marie Souriau , Roland Triay

We investigate the properties of clusters of galaxies in the $\Lambda$CDM models with a steplike initial power spectrum. We examine the mass function, the peculiar velocities and the power spectrum of clusters in models with different…

天体物理学 · 物理学 2011-07-19 Mirt Gramann , Gert H"utsi