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相关论文: Large--Scale Angular Correlations in CDM Models

200 篇论文

We study the directional dependence of the angular two-point correlation function in maps of the cosmic microwave background (CMB). We propose two new statistics, one which measures the correlation of each point in the sky with a ring of…

宇宙学与河外天体物理 · 物理学 2012-03-20 Sophie Zhang

We compute the two-point angular correlation function $w(\theta)$ for a sample of $\sim$ 1700 galaxies to a magnitude-limit equivalent to $R \sim 29.5$ using a catalog derived from the Hubble Deep Field images. A non zero value of…

天体物理学 · 物理学 2009-10-28 Jens V. Villumsen , Wolfram Freudling , Luiz N. da Costa

We apply a new method to measure primordial non-Gaussianity, using the cross-correlation between galaxy surveys and the CMB lensing signal to measure galaxy bias on very large scales, where local-type primordial non-Gaussianity predicts a…

宇宙学与河外天体物理 · 物理学 2014-06-06 Tommaso Giannantonio , Will J. Percival

We determine the evolution from $z=3\to 0$ of the galaxy and mass correlation functions and bias factor in a $50h^{-1}$Mpc $\Lambda$CDM hydrodynamic simulation with $10h^{-1}$kpc resolution. The mass correlation function grows with time,…

天体物理学 · 物理学 2007-05-23 Romeel Davé , Lars Hernquist , Neal Katz , David H. Weinberg

We investigate the evolution of the skewness of the distribution of density fluctuations in CDM models with both Gaussian and non--Gaussian initial fluctuations. We show that the method proposed by Coles \& Frenk (1991), which uses the…

天体物理学 · 物理学 2015-06-24 P. Coles , L. Moscardini , F. Lucchin , S. Matarrese , A. Messina

We investigate the clustering of high redshift galaxies in five variants of the cold dark matter (CDM) scenario, using hydrodynamic cosmological simulations that resolve the formation of systems with circular velocities $v_c \geq 100 \kms$…

天体物理学 · 物理学 2009-10-30 Neal Katz , Lars Hernquist , David H. Weinberg

We carry out a comprehensive hierarchical multi-scale morphological analysis to search for anomalous behaviour in the large scale matter distribution using convergence map provided by the Atacama Cosmology Telescope (ACT) Data Release 6. We…

宇宙学与河外天体物理 · 物理学 2025-03-25 Masroor Bashir , Nidharssan S , Pravabati Chingangbam , Fazlu Rahman , Priya Goyal , Stephen Appleby , Changbom Park

We compare the large scale galaxy clustering in the new SDSS early data release (EDR) with the clustering in the APM Galaxy Survey. We cut out pixel maps (identical in size and shape) from the SDSS and APM data to allow a direct comparison…

天体物理学 · 物理学 2009-11-06 E. Gaztanaga

Several recent studies show that bright, intermediate and high redshift optically and radio selected QSOs are positively correlated with nearby galaxies on a range of angular scales up to a degree. Obscuration by unevenly distributed…

天体物理学 · 物理学 2009-10-31 Liliya L. R. Williams

We analyse with simple real-space statistics the Virgo consortium's cosmological N-body simulations. Significant clustering rapidly develops well below the initial mean interparticle separation \Lambda_i, where the gravitational force on a…

天体物理学 · 物理学 2009-11-07 Thierry Baertschiger , Michael Joyce , Francesco Sylos Labini

The angular two-point correlation function of the temperature of the cosmic microwave background (CMB), as inferred from nearly all-sky maps, is very close to zero on large angular scales. A statistic invented to quantify this feature,…

宇宙学与河外天体物理 · 物理学 2017-05-04 Robert Knight , Lloyd Knox

Recent results from a number of redshift surveys suggest that the Universe is well described by an inhomogeneous, fractal distribution on the largest scales probed. This distribution has been found to have fractal dimension, D,…

天体物理学 · 物理学 2009-10-31 S. J. Hatton

We compare the specific angular momentum profiles of virialized dark halos in cold dark matter (CDM) and warm dark matter (WDM) models using high-resolution dissipationless simulations. The simulations were initialized using the same set of…

天体物理学 · 物理学 2009-11-07 James S. Bullock , Andrey V. Kravtsov , Pedro Colin

We introduce the basic techniques used for the analysis of three dimensional and two dimensional galaxy samples. We report the correlation analysis of various redshift surveys which shows that the available data are consistent with each…

天体物理学 · 物理学 2007-05-23 L. Pietronero , F. Sylos Labini , M. Montuori

The gravitational coupling of a long-wavelength tidal field with small-scale density fluctuations leads to anisotropic distortions of the locally measured small-scale matter correlation function. Since the local correlation function is…

宇宙学与河外天体物理 · 物理学 2017-12-25 Hong-Ming Zhu , Ue-Li Pen , Yu Yu , Xinzhong Er , Xuelei Chen

In the mixture modeling frame, this paper presents the polynomial Gaussian cluster-weighted model (CWM). It extends the linear Gaussian CWM, for bivariate data, in a twofold way. Firstly, it allows for possible nonlinear dependencies in the…

统计方法学 · 统计学 2012-07-05 Antonio Punzo

The galaxy correlation function serves as a fundamental tool for studying cosmology, galaxy formation, and the nature of dark matter. It is well established that more massive, redder and more compact galaxies tend to have stronger…

宇宙学与河外天体物理 · 物理学 2025-05-27 Ziwen Zhang , Yangyao Chen , Yu Rong , Huiyuan Wang , Houjun Mo , Xiong Luo , Hao Li

We search for hidden mirror symmetries at large angular scales in the WMAP 7 year Internal Linear Combination map of CMB temperature anisotropies using global pixel based estimators introduced for this aim. Two different axes are found for…

宇宙学与河外天体物理 · 物理学 2015-03-19 F. Finelli , A. Gruppuso , F. Paci , A. A. Starobinsky

We detect angular galaxy-QSO cross-correlations between the APM Galaxy Catalogue and a preliminary release (consisting of roughly half of the anticipated final catalogue) of the Hamburg-ESO Catalogue of Bright QSOs as a function of source…

天体物理学 · 物理学 2009-11-13 Joshua G. Nollenberg , Liliya L. R. Williams

We have simulated cosmic microwave background (CMB) anisotropy maps for several COBE-DMR-normalized cold dark matter (CDM) cosmogonies, to make predictions for the upcoming MAP experiment. We have studied the sensitivity of the simulated…