相关论文: Detecting Adiabatic Contraction in Rotation Curves

We use high resolution numerical simulations to investigate the adiabatic contraction of dark matter halos with a Hernquist density profile. We test the response of the halos to the growth of additional axisymmetric disk potentials with…

The density profiles of dark matter haloes are commonly described by fitting functions such as the NFW or Einasto models, but these approximations break down in the transition region where halos become dominated by newly accreting matter.…

The latest cosmological N-body simulations find two intriguing properties for dark matter haloes: (1) their radial density profile, rho, is better fit by a form that flattens to a constant at the halo center (the Einasto profile) than the…

A simple analytical model for describing inner parts of dark matter halo is considered. It is assumed that dark matter density is power-law. The model deals with dark matter distribution function in phase space of adiabatic invariants…

Kinematics and photometry of the polar ring galaxy NGC 4650A, including new observations of the rotation and velocity dispersion of its central stellar disk, are used to infer the presence of a dark matter halo and to measure its shape.…

The adiabatic growth of a central massive black hole could compress the surrounding dark matter halo, leading to a steeper profile of the dark matter halo. This phenomenon is called adiabatic compression. We investigate the adiabatic…

The isolation, simple apparent structure, and low luminosity of the nearby spiral galaxy NGC 6503 make it an ideal candidate for an in-depth kinematic and photometric study. We introduce a new publicly available code, DiskFit, that…

We revisit the massive isolated elliptical galaxy / fossil group NGC 6482 for which previous X-ray studies of a modest Chandra observation obtained a very uncertain, but also possibly very high, halo concentration. We present new…

Existing long-slit spectral data for edge-on spiral galaxies suggesting that their Diffuse Ionized Gas (DIG) halos rotate slower than their underlying disks are summarized. An attempt to characterize lagging halos using a model of purely…

Cosmological simulations predict dark matter shapes that deviate from spherical symmetry. The exact shape depends on the prescription of the simulation and the interplay between dark matter and baryons. This signature is most pronounced in…

Using N-body simulations we study the phenomenon of radial orbit instability occurring in dark matter haloes of the size of a dwarf galaxy. We carried out simulations of seven spherical models, with the same standard NFW density profile but…

The spiral galaxy NGC 6503 exhibits a regular kinematical structure except for a remarkable drop of the stellar velocity dispersion values in the central region. To investigate the dynamics of the disc a theoretical framework has been…

We have analyzed galaxy and group-sized dark matter halos formed in a high resolution LCDM numerical N-body simulation in order to study the rotation of the triaxial figure, a property in principle independent of the angular momentum of the…

We use Bayesian statistics and Markov chain Monte Carlo (MCMC) techniques to construct dynamical models for the spiral galaxy NGC 6503. The constraints include surface brightness profiles which display a Freeman Type II structure; HI and…

We study the profiles of 75 086 elliptical galaxies from the Sloan Digital Sky Survey (SDSS) at both large (50-500 kpc/h) and small (~3 kpc/h) scales. Weak lensing observations in the outskirts of the halo are combined with measurements of…

The adiabatic condition governing cyclic adiabatic inversion of proton spins in a micron-sized ammonium chloride crystal was studied using room temperature nuclear magnetic resonance force microscopy. A systematic degradation of…

Observations show that the underlying rotation curves at intermediate radii in spiral and low-surface brightness galaxies are nearly universal. Further, in these same galaxies, the product of the central density and the core radius…

We describe a generalization of the asymptotic calculation of the tidal torques experienced by a massive star as a result of a companion in circular orbit originally considered by Zahn (1975,1977) to the case of a rotating star when the…

We perform a non-radial adiabatic perturbation analysis on homologous conventional polytropic stellar core collapses. The core collapse features a polytropic exponent $\Gamma=4/3$ relativistic gas under self-gravity of spherical symmetry…

The equilibrium configurations of slowly rotating anisotropic self-gravitating fluids are computed using the extended Hartle structure equations, including anisotropic effects, derived in our previous paper. We focus on the so-called…