中文
相关论文

相关论文: Analytical Solutions to the Mass-Anisotropy Degene…

200 篇论文

A widely employed method for estimating the mass of stellar systems with apparent spherical symmetry is dynamical modelling using the spherically symmetric Jeans equation. Unfortunately this approach suffers from a degeneracy between the…

星系天体物理 · 物理学 2015-06-19 Foivos I. Diakogiannis , Geraint F. Lewis , Rodrigo A. Ibata

The spherical Jeans equation is widely used to estimate the mass content of a stellar systems with apparent spherical symmetry. However, this method suffers from a degeneracy between the assumed mass density and the kinematic anisotropy…

星系天体物理 · 物理学 2015-06-19 Foivos I. Diakogiannis , Geraint F. Lewis , Rodrigo A. Ibata

We attempt to measure the density of dark matter in the two Dwarf Spheroidal Galaxies Fornax and Sculptor using a new method which employs Jeans equations based on both the second and fourth moment of the Collisionless Boltzmann Equation…

星系天体物理 · 物理学 2013-05-06 Thomas Richardson , Malcolm Fairbairn

We present an innovative approach to the methodology of dynamical modelling, allowing practical reconstruction of the underlying dark matter mass without assuming both the density and anisotropy functions. With this, the mass-anisotropy…

We test a non-parametric higher-order Jeans analysis method, GravSphere, on 32 simulated dwarf galaxies comparable to classical Local Group dwarfs like Fornax. The galaxies are selected from the APOSTLE suite of cosmological hydrodynamics…

Traditionally, the mass / velocity anisotropy degeneracy (MAD) inherent in the spherical, stationary, non-streaming Jeans equation has been handled by assuming a mass profile and fitting models to the observed kinematical data. Here, the…

宇宙学与河外天体物理 · 物理学 2010-02-11 Gary A. Mamon , Gwenael Boué

Mass-modeling methods are used to infer the gravitational field of stellar systems, from globular clusters to giant elliptical galaxies. While many methods exist, most require assumptions about the form of the underlying distribution…

星系天体物理 · 物理学 2026-04-17 Andrés Bañares-Hernández , Justin I. Read , Mariana P. Júlio

We present an analytic approach to lift the mass-anisotropy degeneracy in clusters of galaxies by utilizing the line-of-sight velocity dispersion of clustered galaxies jointly with weak lensing inferred masses. More specifically, we solve…

宇宙学与河外天体物理 · 物理学 2019-05-28 Alejo Stark , Christopher J. Miller , Vitali Halenka

We present a new method for studying tracers in gravitational systems where higher moments of the line-of-sight velocity distribution are introduced via Virial equations rather than the Jeans equations. Unlike the fourth order Jeans…

星系天体物理 · 物理学 2014-04-25 Thomas Richardson , Malcolm Fairbairn

One can solve the Jeans equation analytically for equilibrated dark matter structures, once given two pieces of input from numerical simulations. These inputs are 1) a connection between phase-space density and radius, and 2) a connection…

天体物理学 · 物理学 2015-06-24 Steen H. Hansen , Ben Moore , Joachim Stadel

Dwarf galaxies, among the most dark matter dominated structures of our universe, are excellent test-beds for dark matter theories. Unfortunately, mass modelling of these systems suffers from the well documented mass-velocity anisotropy…

Axisymmetric Jeans modelling is widely used to infer galaxy mass profiles from integral-field kinematics, but existing implementations maintain tractability by adopting highly restricted anisotropy prescriptions. I present a new spectral…

星系天体物理 · 物理学 2026-03-03 Michele Cappellari

Distinguishing a core and a cusp within dark matter halos is complexified by the existence of mass-anisotropy degeneracy, where various combinations of velocity anisotropy ($\beta$) and inner density slope ($\gamma$) yield similar…

星系天体物理 · 物理学 2025-02-21 Dafa Wardana , Masashi Chiba , Kohei Hayashi

One can solve the Jeans equation analytically for equilibrated dark matter structures, once given two pieces of input from numerical simulations. These inputs are 1) a connection between phase-space density and radius, and 2) a connection…

天体物理学 · 物理学 2009-11-13 Steen H. Hansen , Joachim Stadel

We present a new method for determining the local dark matter density using kinematic data for a population of tracer stars. The Jeans equation in the $z$-direction is integrated to yield an equation that gives the velocity dispersion as a…

星系天体物理 · 物理学 2016-05-10 Hamish Silverwood , Sofia Sivertsson , Pascal Steger , Justin I. Read , Gianfranco Bertone

The distribution of dark matter in dwarf galaxies can have important implications on our understanding of galaxy formation as well as the particle physics properties of dark matter. However, accurately characterizing the dark matter content…

宇宙学与河外天体物理 · 物理学 2021-09-01 Laura J. Chang , Lina Necib

The inner profile of Dark Matter (DM) halos remains one of the central problems in small-scale cosmology. At present, the problem can not be resolved in dwarf spheroidal galaxies due to a degeneracy between the DM profile and the velocity…

星系天体物理 · 物理学 2014-03-19 Thomas Richardson , Douglas Spolyar , Matt Lehnert

In the solution of the Jeans equations for axisymmetric galaxy models the ``$b$-ansatz" is often adopted to prescribe the relation between the vertical and radial components of the velocity dispersion tensor, and close the equations.…

星系天体物理 · 物理学 2025-11-05 Leonardo De Deo , Luca Ciotti , Silvia Pellegrini

The kinematics of stars in dwarf spheroidal galaxies have been studied to understand the structure of dark matter halos. However, the kinematic information of these stars is often limited to celestial positions and line-of-sight velocities,…

星系天体物理 · 物理学 2025-06-03 Sung Hak Lim , Kohei Hayashi , Shun'ichi Horigome , Shigeki Matsumoto , Mihoko M. Nojiri

We present the theoretical framework to efficiently solve the Jeans equations for multi-component axisymmetric stellar systems, focusing on the scaling of all quantities entering them. The models may include an arbitrary number of stellar…

星系天体物理 · 物理学 2021-06-30 C. Caravita , L. Ciotti , S. Pellegrini
‹ 上一页 1 2 3 10 下一页 ›