English
Related papers

Related papers: Non-Parametric Spherical Jeans Mass Estimation wit…

200 papers

We construct a fully self-consistent mass model for the lens galaxy J2141 at z=0.14, and use it to improve on previous studies by modelling its gravitational lensing effect, gas rotation curve and stellar kinematics simultaneously. We adopt…

We propose a new method for measuring the spatial density distribution of the stellar halo of the Milky Way. Our method is based on a pairwise statistic of the distribution of stars on the sky, the angular two-point correlation function…

Astrophysics of Galaxies · Physics 2023-08-09 Anda Chen , Zhigang Li , Yougang Wang , Yan Gong , Xuelei Chen , Richard J. Long

Galaxies and the dark matter halos that host them are not spherically symmetric, yet spherical symmetry is a helpful simplifying approximation for idealised calculations and analysis of observational data. The assumption leads to an exact…

Astrophysics of Galaxies · Physics 2016-01-29 Andrew Pontzen , Justin Read , Romain Teyssier , Fabio Governato , Alessia Gualandris , Nina Roth , Julien Devriendt

Hidden Markov models (HMMs) are flexible time series models in which the distributions of the observations depend on unobserved serially correlated states. The state-dependent distributions in HMMs are usually taken from some class of…

Methodology · Statistics 2014-06-19 Roland Langrock , Thomas Kneib , Alexander Sohn , Stacy DeRuiter

Weak lensing three-point statistics are powerful probes of the structure of dark matter halos. We propose to use the correlation of the positions of galaxies with the shapes of background galaxy pairs, known as the halo-shear-shear…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-07 Masato Shirasaki , Naoki Yoshida

We revisit systematics in determining the local dark matter density (rho_dm) from the vertical motion of stars in the Solar Neighbourhood. Using a simulation of a Milky Way-like galaxy, we determine the data-quality required to detect the…

Astrophysics of Galaxies · Physics 2011-08-29 Silvia Garbari , Justin I. Read , George Lake

Although numerous dynamical techniques have been developed to estimate the total dark matter halo mass of the Milky Way, it remains poorly constrained, with typical systematic uncertainties of 0.3 dex. In this study, we apply a neural…

Astrophysics of Galaxies · Physics 2025-10-03 Elaheh Hayati , Peter Behroozi , Ekta Patel , Yunchong Wang , Stefan Gottlöber , Gustavo Yepes

The Jeans gravitational instability in nonextensive statistical mechanics is studied and a general form of the generalized Jeans criterion is obtained that is related to the q-function . In this approach, the nonextensive model of classical…

Astrophysics · Physics 2015-08-10 Jiulin Du

Starting from a very accurate model for density-in-cells statistics of dark matter based on large deviation theory, a bias model for the tracer density in spheres is formulated. It adopts a mean bias relation based on a quadratic bias model…

The degeneracy between disc and halo contributions in spiral galaxy rotation curves makes it difficult to obtain a full understanding of the distribution of baryons and dark matter in disc galaxies like our own Milky Way. Using mock data,…

Astrophysics of Galaxies · Physics 2019-03-27 Samantha Scibelli , Rosalba Perna , Charles Keeton

We estimate the enclosed mass profile in the central 10 pc of the Milky Way by analyzing the infrared photometry and the velocity observations of dynamically relaxed stellar population in the Galactic center. HST/NICMOS and Gemini Adaptive…

Astrophysics of Galaxies · Physics 2017-01-18 Seungkyung Oh , Sungsoo S. Kim , Donald F. Figer

The time evolution of initially balanced, rapidly rotating models for an isolated disk of highly flattened galaxies of stars is calculated. The method of direct integration of the Newtonian equations of motion of stars over a time span of…

Astrophysics · Physics 2007-05-23 Evgeny Griv , Michael Gedalin , Edward Liverts , David Eichler , Yehoshua Kimhi , Chi Yuan

We examine the necessity of resolving the Jeans mass in hydrodynamical simulations of the hierarchical formation of cosmological structures. We consider a standard two-component fluid and use smoothed particle hydrodynamics to model the…

Astrophysics · Physics 2009-10-31 Eric R. Tittley , H. M. P. Couchman

[abridged] In the dark matter (DM) halos embedding galaxies and galaxy systems the `entropy' K = \sigma^2 / \rho^{2/3} (a quantity that combines the radial velocity dispersion \sigma with the density \rho) is found from intensive N-body…

Astrophysics · Physics 2011-02-11 A. Lapi , A. Cavaliere

For many analyses in cosmology it is necessary to reconstruct the likely distribution of unobserved fields, such as dark matter or non-luminous baryons, from observed luminous tracers. The dominant approach in cosmology has been to use the…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-16 Jordan Krywonos , Yurii Kvasiuk , Matthew C. Johnson , Moritz Münchmeyer

We use high-resolution N-body simulations to study the equilibrium density profiles of dark matter halos in hierarchically clustering universes. We find that all such profiles have the same shape, independent of halo mass, of initial…

Astrophysics · Physics 2008-11-26 Julio F. Navarro , Carlos S. Frenk , Simon D. M. White

We perform an extensive review of the numerous studies and methods used to determine the total mass of the Milky Way. We group the various methods into seven broad classes, including: i) estimating Galactic escape velocity using high…

Astrophysics of Galaxies · Physics 2020-05-13 Wenting Wang , Jiaxin Han , Marius Cautun , Zhaozhou Li , Miho N. Ishigaki

The observed stellar kinematics of dispersion-supported galaxies are often used to measure dynamical masses. Recently, several analytical relationships between the stellar line-of-sight velocity dispersion, the projected (2D) or deprojected…

The distribution of shapes of galaxies' dark halos provides a basic test for models of galaxy formation. To-date, few dark halo shapes have been measured, and the results of different methods appear contradictory. Here, we add to the sample…

Astrophysics · Physics 2007-05-23 R. P. Olling , M. R. Merrifield

We present "sheet+release" simulations that reliably follow the evolution of dark matter structure at and below the dark matter free-streaming scale, where instabilities in traditional N-body simulations create a large population of…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-03 Jens Stücker , Raul E. Angulo , Oliver Hahn , Simon D. M. White