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相关论文: Measuring Galaxy Asymmetries in 3D

200 篇论文

The breakdown of statistical homogeneity and isotropy of cosmic perturbations is a generic feature of ultra large scale structure of the cosmos, in particular, of non trivial cosmic topology. The statistical isotropy (SI) of the Cosmic…

天体物理学 · 物理学 2007-05-23 Amir Hajian , Tarun Souradeep

We present a method to infer reddenings and distances to stars, based only on their broad-band photometry, and show how this method can be used to produce a three-dimensional dust map of the Galaxy. Our method samples from the full…

A general inversion technique for the recovery of the underlying distribution function for observed galactic disks is presented and illustrated. Under the assumption that these disks are axi-symmetric and thin, the proposed method yields…

天体物理学 · 物理学 2009-09-25 C. Pichon , E. Thiebaut

We constrain the linear and quadratic bias parameters from the configuration dependence of the three-point correlation function (3PCF) in both redshift and projected space, utilizing measurements of spectroscopic galaxies in the Sloan…

Statistical analyses of finite sample distributions usually assume that fluctuations are self-averaging, i.e. that they are statistically similar in different regions of the given sample volume. By using the scale-length method, we test…

宇宙学与河外天体物理 · 物理学 2010-11-02 Francesco Sylos Labini , Nikolay L. Vasilyev , Yurij V. Baryshev

We show that the growth curves of galaxies can be used to determine their bulge and disk parameters and bulge-to-total luminosity ratios, in addition to their conventional asymptotic magnitudes, provided that the point spread function is…

天体物理学 · 物理学 2009-10-31 Sadanori Okamura , Naoki Yasuda , Kazuhiro Shimasaku , Masafumi Yagi , David H. Weinberg

Morphological classification conveys abundant information on the formation, evolution, and environment of galaxies. In this work, we refine the two-step galaxy morphological classification framework ({\tt\string USmorph}), which employs a…

星系天体物理 · 物理学 2024-04-25 Jie Song , GuanWen Fang , Shuo Ba , Zesen Lin , Yizhou Gu , Chichun Zhou , Tao Wang , Cai-Na Hao , Guilin Liu , Hongxin Zhang , Yao Yao , Xu Kong

Geostatistical methods are powerful tools for understanding the spatial structure of the metallicity distribution of galaxies, and enable construction of accurate predictive models of the 2D metallicity distribution. However, so far these…

星系天体物理 · 物理学 2024-02-15 Benjamin Metha , Michele Trenti , Andrew Battisti , Tingjin Chu

While galaxies with clockwise and counterclockwise handedness are visually different, they are expected to be symmetric in all of their other characteristics. Previous experiments using both manual analysis and machine vision have shown…

星系天体物理 · 物理学 2017-03-08 Lior Shamir

Nonlinear combinations of direct observables are often used to estimate quantities of theoretical interest. Without sufficient caution, this could lead to biased estimations. An example of great interest is the skewness $S_3$ of the galaxy…

天体物理学 · 物理学 2009-10-31 Lam Hui , Enrique Gaztanaga

Photometric redshifts are commonly used to measure the distribution of galaxies in large surveys. However, the demands of ongoing and future large-scale cosmology surveys place very stringent limits on the redshift performance that are…

宇宙学与河外天体物理 · 物理学 2022-10-11 Philipp Sudek , Lucia F. de la Bella , Adam Amara , William G. Hartley

Context. The density split statistics in weak gravitational lensing analyses probes the correlation between regions of different (foreground) galaxy number densities and their weak lensing signal, measured by the shape distortion of…

The statistical properties of the ellipticities of galaxy images depend on how galaxies form and evolve, and therefore constrain models of galaxy morphology, which are key to the removal of the intrinsic alignment contamination of…

宇宙学与河外天体物理 · 物理学 2013-05-28 B. Joachimi , E. Semboloni , P. E. Bett , J. Hartlap , S. Hilbert , H. Hoekstra , P. Schneider , T. Schrabback

In this article we propose a novel test for statistical anisotropy of the CMB. The test is based on the fact, that the Galactic foregrounds have a remarcably strong symmetry with respect to their antipodal points and with respect to the…

宇宙学与河外天体物理 · 物理学 2015-05-28 P. Naselsky , M. Hansen , J. Kim

We investigate the impact of the observed correlation between a galaxies shape and its surrounding density field on the measurement of third order weak lensing shear statistics. Using numerical simulations, we estimate the systematic error…

天体物理学 · 物理学 2009-11-13 Elisabetta Semboloni , Catherine Heymans , Ludovic van Waerbeke , Peter Schneider

The morphology and kinematics of atomic Hydrogen (HI) gas in galaxies are influenced by both local and large scale cosmic environments. Differences in galaxy environment and interactions can leave distinct signatures in HI asymmetry,…

星系天体物理 · 物理学 2025-08-05 P. V. Bilimogga , E. Busekool , M. A. W. Verheijen , J. M. van der Hulst

The low statistical errors on cosmological parameters promised by future galaxy surveys will only be realised with the development of new, fast, analysis methods that reduce potential systematic problems to low levels. We present an…

宇宙学与河外天体物理 · 物理学 2016-11-23 Rossana Ruggeri , Will Percival , Héctor Gil-Marín , Fangzhou Zhu , Gongbo Zhao , Yuting Wang

We consider the benefits of measuring cosmic statistical anisotropy from redshift-space correlators of the galaxy number density fluctuation and the peculiar velocity field without adopting the plane-parallel (PP) approximation. Since the…

宇宙学与河外天体物理 · 物理学 2021-03-17 Maresuke Shiraishi , Teppei Okumura , Kazuyuki Akitsu

We develop a cosmological parameter estimation code for (tomographic) angular power spectra analyses of galaxy number counts, for which we include, for the first time, redshift-space distortions (RSD) in the Limber approximation. This…

宇宙学与河外天体物理 · 物理学 2020-09-15 Konstantinos Tanidis , Stefano Camera