The mass of dwarf spheroidal galaxies and the missing satellite problem
نویسندگان
چکیده
We present the results from a suite of N-body simulations of the tidal stripping of twocomponent dwarf galaxies comprising some stars and dark matter. We show that recent kinematic data from the local group dwarf spheroidal (dSph) galaxies suggests that dSph galaxies must be sufficiently massive (10 − 1010M⊙) that tidal stripping is of little importance for the stars. We discuss the implications of these massive dSph galaxies for cosmology and galaxy formation.
منابع مشابه
Modeling Star Formation in Dwarf Spheroidal Galaxies: a Case for Extended Dark Matter Halos
We propose a simple model for the formation of dwarf spheroidal galaxies, in which stars are assumed to have formed from isothermal gas in hydrostatic equilibrium inside extended dark matter halos. After expelling the leftover gas, the stellar system undergoes a dynamical relaxation inside the dark matter halo. These models can adequately describe the observed properties of three (Draco, Sculpt...
متن کاملDwarf Spheroidal Satellite Galaxies Without Dark Matter: Results From Two Different Numerical Techniques
Self-consistent simulations of the dynamical evolution of a low-mass satellite galaxy without dark matter are reported. The orbits have eccentricities 0.41 ≤ e ≤ 0.96 in a Galactic dark halo with a mass of 2.85 × 10 M⊙ and 4.5 × 10 M⊙. For the simulations, a particle-mesh code with nested sub-grids and a direct-summation N-body code running with the special purpose hardware device Grape are use...
متن کاملA Model for Dwarf Spheroidal Satellite Galaxies Without Dark Matter
Self-consistent simulations of the dynamical evolution of low-mass satellite galaxies without dark matter on different orbits interacting with an extended Galactic dark halo are described. The calculations proceed for many orbital periods until well after the satellite dissolves. In all cases the dynamical evolution converges to a remnant that contains roughly 1 per cent of the initial satellit...
متن کاملar X iv : a st ro - p h / 96 12 02 8 v 1 3 D ec 1 99 6 DWARF SPHEROIDAL
The Milky Way is surrounded by nine or more dwarf-spheroidal (dSph) satellite galaxies that appear to consist primarily of dark matter. Here I summarise research that shows that initially spherical bound low-mass satellites without dark matter, that are on orbits within a massive Galactic dark corona, can evolve into remnants that are non-spherical, have a non-isotropic velocity dispersion tens...
متن کاملSearch for HI in Dwarf Spheroidal Galaxies
After reviewing the HI content and distribution in extreme dwarf irregular (dIrr) and dwarf elliptical (dE) galaxies, previous searches for HI in dwarf spheroidal (dSph) galaxies will be discussed. I will report on the recent detections of HI probably associated with the Local Group (LG) dSph Sculptor and dIrr/dSph Phoenix, obtained with the ATCA, along with a similar detection in the Centaurus...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2005