English
Related papers

Related papers: Structure formation: a spherical model for the evo…

200 papers

We have measured the clustering properties of low-redshift (z < 0.3) sub-mm galaxies detected at 250 micron in the Herschel-ATLAS Science Demonstration Phase (SDP) field. We selected a sample for which we have high-quality spectroscopic…

We find clusters and superclusters of galaxies using the Data Release 1 of the Sloan Digital Sky Survey. We determine the luminosity function of clusters and find that clusters in a high-density environment have a luminosity a factor of ~5…

Astrophysics · Physics 2009-11-10 J. Einasto , E. Tago , M. Einasto , E. Saar , I. Suhhonenko , P. Hein"am"aki , G. Huetsi , D. L. Tucker

We probe the evolution of globular clusters that could form in giant molecular clouds within high-redshift galaxies. Numerical simulations demonstrate that the large and dense enough gas clouds assemble naturally in current hierarchical…

Astrophysics · Physics 2009-11-13 Oleg Y. Gnedin , Jose L. Prieto

We apply the scale-length method to several three dimensional samples of the Two degree Field Galaxy Redshift Survey. This method allows us to map in a quantitative and powerful way large scale structures in the distribution of galaxies…

Astrophysics · Physics 2009-08-03 Francesco Sylos Labini , Nikolay L. Vasilyev , Yurij V. Baryshev

We study evolution of various statistical quantities of smoothed cosmic density and velocity fields using N-body simulations. The parameter $C\equiv <V^2\delta>/(<V^2> <\delta^2>)$ characterizes nonlinear coupling of these two fields and…

Astrophysics · Physics 2016-08-30 Naoki Seto , Naoshi Sugiyama

In hierarchical cosmologies the evolution of galaxy clustering depends both on cosmological quantities such as Omega and Lambda, which determine how dark matter halos form and evolve, and on the physical processes - cooling, star formation…

We report on the construction of a granular network of particles to study the formation, evolution and statistical properties of clusters of particles developing at the vicinity of a liquid-solid-like phase transition within a vertically…

Statistical Mechanics · Physics 2023-12-25 Enrique Navarro , Claudio Falcón

The formalism by Press and Schechter (PS) is often used to infer number densities of virialized objects of mass M (e.g. quasars, galaxies, clusters of galaxies, etc.) from a count of initially overdense regions in a Gaussian density…

Astrophysics · Physics 2009-10-22 K. Jedamzik

A numerical hydrodynamical model for the evolution of spherically symmetric collapsing clouds, designed for the calculation of the thermal structure of these objects in both the prestellar and protostellar stages of their evolution, is…

Astrophysics of Galaxies · Physics 2015-06-23 Ya. N. Pavlyuchenkov , A. G. Zhilkin , E. I. Vorobyov , A. M. Fateeva

We consider a kinetic model, which describes the sedimentation of rod-like particles in dilute suspensions under the influence of gravity. This model has recently been derived by Helzel and Tzavaras in \cite{HT2015}. Here we restrict our…

Fluid Dynamics · Physics 2017-03-09 Christiane Helzel , Athanasios E. Tzavaras

In the cold dark matter model of structure formation, galaxies are assembled hierarchically from mergers and the accretion of subclumps. This process is expected to leave residual substructure in the Galactic dark halo, including partially…

Astrophysics · Physics 2009-11-06 D. Stiff , L. M. Widrow , J. Frieman

We introduce a simple model of population dynamics which considers birth and death rates for every individual that depend on the number of particles in its neighborhood. The model shows an inhomogeneous quasistationary pattern with many…

Condensed Matter · Physics 2009-11-10 Emilio Hernandez-Garcia , Cristobal Lopez

Motivated by learning dynamical structures from static snapshot data, this paper presents a distribution-on-scalar regression approach for estimating the density evolution of a stochastic process from its noisy temporal point clouds. We…

Statistics Theory · Mathematics 2025-02-26 Rentian Yao , Atsushi Nitanda , Xiaohui Chen , Yun Yang

An introduction is given to projects investigating galaxy evolution quantitatively by spectroscopic observations of very distant galaxies that have weak apparent brightnesses and small sizes as it is feasible with 10m-class telescopes like…

Astrophysics · Physics 2007-05-23 Bodo L. Ziegler

We introduce the concept of a class of equivalence of molecular clouds represented by an abstract spherically symmetric, isotropic object. This object is described by use of abstract scales in respect to a given mass density distribution.…

Astrophysics of Galaxies · Physics 2017-01-18 Sava Donkov , Todor V. Veltchev , Ralf S. Klessen

We report three-dimensional particle mechanics static calculations that predict the microstructure evolution during die-compaction of elastic spherical particles up to relative densities close to one. We employ a nonlocal contact…

Soft Condensed Matter · Physics 2016-08-03 Marcial Gonzalez , Alberto M. Cuitino

The density-distribution method has recently become a promising paradigm owing to its adaptability to variations in swarm size. However, existing studies face practical challenges in achieving complex shape representation and decentralized…

Robotics · Computer Science 2026-02-03 Yichen Cai , Yuan Gao , Pengpeng Li , Wei Wang , Guibin Sun , Jinhu Lü

Monolayer cluster growth in far-from-equilibrium systems is investigated by applying simulation and analytic techniques to minimal hard core particle (exclusion) models. The first model (I), for post-deposition coarsening dynamics, contains…

Statistical Mechanics · Physics 2009-11-10 F. D. A. Aarao Reis , R. B. Stinchcombe

We present a method to derive the density scaling relation $\langle n\rangle \propto L^{-\alpha}$ in regions of star formation or in their turbulent vicinities from straightforward binning of the column-density distribution ($N$-pdf). The…

Astrophysics of Galaxies · Physics 2017-05-19 Todor Veltchev , Sava Donkov , Orlin Stanchev

We study scaling properties of stochastic aggregation processes in one dimension. Numerical simulations for both diffusive and ballistic transport show that the mass distribution is characterized by two independent nontrivial exponents…

Statistical Mechanics · Physics 2007-05-23 E. Ben-Naim , P. L. Krapivsky