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相关论文: Mapping stationary axisymmetric phase-space distri…

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This paper investigates probability density functions (PDFs) that are continuous everywhere, nearly uniform around the mode of distribution, and adaptable to a variety of distribution shapes ranging from bell-shaped to rectangular. From the…

机器学习 · 计算机科学 2022-04-01 Osamu Fujita

A method is developed to compute the chord length distribution along a line which intersects a cellular Universe. The cellular Universe is here modeled by the Poissonian Voronoi Tessellation (PVT) and by a non-Poissonian Voronoi…

宇宙学与河外天体物理 · 物理学 2013-03-26 L. Zaninetti

We study the possibility of using the entire probability distribution function (PDF) of the aperture mass Map and its related cumulative probability distribution function (CPDF) to obtain meaningful constraints on cosmological parameters.…

天体物理学 · 物理学 2007-05-23 Dipak Munshi , Patrick Valageas

We conduct numerical experiments to determine the density probability distribution function (PDF) produced in supersonic, isothermal, self-gravitating turbulence of the sort that is ubiquitous in star-forming molecular clouds. Our…

星系天体物理 · 物理学 2021-08-10 Shivan Khullar , Christoph Federrath , Mark R. Krumholz , Christopher D. Matzner

We introduce new efficient integral representations and methods for evaluation of pdfs, cpds and quantiles of stable distributions. For wide regions in the parameter space, absolute errors of order $10^{-15}$ can be achieved in 0.005-0.1…

数值分析 · 数学 2018-08-14 Svetlana Boyarchenko , Sergei Levendorskiĭ

We examine the coarse-grained phase-space density profiles of a set of recent, high-resolution simulations of galaxy-sized Cold Dark Matter (CDM) halos. Over two and a half decades in radius the phase-space density closely follows a…

天体物理学 · 物理学 2009-11-06 James E. Taylor , Julio F. Navarro

Dynamical models are used to study dark matter (DM) in galaxies, how galaxies assemble through mergers, and to test galaxy formation models. Despite its widespread use, there has been no systematic study quantifying how much information can…

星系天体物理 · 物理学 2025-11-14 Paula Gherghinescu , Eugene Vasiliev , Payel Das , Justin Read

We present a new method for emulating the halo mass function (HMF) and other distribution functions in large effective volumes, down to low halo masses, whilst simultaneously modifying large ranges of parameters, for a fraction of the cost…

We review the analysis of the Cosmic Web by means of an extensive toolset based on the use of Delaunay and Voronoi tessellations. The Cosmic Web is the salient and pervasive foamlike pattern in which matter has organized itself on scales of…

天体物理仪器与方法 · 物理学 2009-12-18 Rien van de Weygaert , Miguel A. Aragon-Calvo , Bernard J. T. Jones , Erwin Platen

In this work we propose an efficient and accurate multi-scale optical simulation algorithm by applying a numerical version of slowly varying envelope approximation in FEM. Specifically, we employ the fast iterative method to quickly compute…

光学 · 物理学 2024-12-03 Fan Xiao , Jingwei Wang , Zhongfei Xiong , Yuntian Chen

We conduct the cosmological analysis by using the lens-redshift distribution test with updated galaxy-scale strong lensing sample, where the considered scenarios involve three typical cosmological models (i.e., $\Lambda$CDM, $\omega$CDM and…

宇宙学与河外天体物理 · 物理学 2023-05-01 Hui Li , Yun Chen

In this work, we present a novel centroiding method based on Fourier space Phase Fitting(FPF) for Point Spread Function(PSF) reconstruction. We generate two sets of simulations to test our method. The first set is generated by GalSim with…

天体物理仪器与方法 · 物理学 2021-07-12 Tianhuan Lu , Wentao Luo , Jun Zhang , Jiajun Zhang , Hekun Li , Fuyu Dong , Yingke Li , Dezi Liu , Liping Fu , Guoliang Li , Zuhui Fan

To understand the nature of the accelerated expansion of the Universe, we need to combine constraints on the expansion rate and growth of structure. The growth rate is usually extracted from three dimensional galaxy maps by exploiting the…

The gravitational potentials of realistic galaxy models are in general non-integrable, in the sense that they admit orbits that do not have three independent isolating integrals of motion and are therefore chaotic. However, if chaotic…

星系天体物理 · 物理学 2021-09-29 R. Pascale , C. Nipoti , L. Ciotti

We have developed a new method for determining the corotation radii of density waves in disk galaxies, which makes use of the radial distribution of an azimuthal phase shift between the potential and density wave patterns. The approach…

天体物理学 · 物理学 2008-11-26 Xiaolei Zhang , Ronald J. Buta

We investigate the distribution of central velocity dispersions for quiescent galaxies in the SDSS at $0.03 \leq z \leq 0.10$. To construct the field velocity dispersion function (VDF), we construct a velocity dispersion complete sample of…

星系天体物理 · 物理学 2017-08-23 Jubee Sohn , H. Jabran Zahid , Margaret J. Geller

The NASA Magnetospheric Multiscale mission has made in situ diffusion region and kinetic-scale resolution measurements of asymmetric magnetic reconnection for the first time, in the Earth's magnetopause. The principal theoretical tool…

等离子体物理 · 物理学 2017-09-11 O. Allanson , F. Wilson , T. Neukirch , Y. -H. Liu , J. D. B. Hodgson

The computation of the parton distribution functions (PDF) or distribution amplitudes (DA) of hadrons from first principles lattice QCD constitutes a central open problem. In this study, we present and evaluate the efficiency of a selection…

高能物理 - 格点 · 物理学 2019-05-01 Joseph Karpie , Kostas Orginos , Alexander Rothkopf , Savvas Zafeiropoulos

Recently, hybrid bias expansions have emerged as a powerful approach to modelling the way in which galaxies are distributed in the Universe. Similarly, field-level emulators have recently become possible thanks to advances in machine…

宇宙学与河外天体物理 · 物理学 2024-02-15 Marcos Pellejero Ibanez , Raul E. Angulo , Drew Jamieson , Yin Li

Parton distribution functions (PDFs) at large $x$ are poorly constrained by high-energy experimental data, but extremely important for probing physics beyond standard model at colliders. We study the calculation of PDFs at large-$x$ through…

高能物理 - 唯象学 · 物理学 2025-08-05 Xiangdong Ji , Yizhuang Liu , Yushan Su