Related papers: Orbit-based dynamical models of the Sculptor dSph …
We present new proper motion (PM) measurements of the dwarf spheroidal galaxies (dSphs) Draco and Sculptor using multi-epoch images obtained with the Hubble Space Telescope ACS/WFC. Our PM results have uncertainties far lower than previous…
(Abridged) We explore the spatial distribution of stars in the Sculptor dwarf spheroidal (dSph) galaxy over an area of 7.82 deg^2. We identify red giant branch (RGB) starts via Washington M, T_2+DDO51 photometry and a blue horizontal branch…
We construct axisymmetric mass models for dwarf spheroidal (dSph) galaxies in the Milky Way to obtain plausible limits on the non-spherical structure of their dark halos. This is motivated by the fact that the observed luminous parts of the…
The dynamical properties of spherically symmetric galaxy models, where a Jaffe (1983) stellar density profile is embedded in a total mass density decreasing as $r^{-3}$ at large radii, are presented. The orbital structure of the stellar…
We present a new determination of the mass content of the Sculptor dwarf spheroidal galaxy, based on a novel approach which takes into account the two distinct stellar populations present in this galaxy. This method helps to partially break…
We use orbit based dynamical models to fit the 2nd and 4th moments of the line of sight velocity distributions of the Fornax, Sculptor, Carina and Sextans dwarf spheroidal galaxies. Our goal is to compare dark matter profile models of these…
We study the distribution of dark matter in dwarf spheroidal galaxies by modelling the moments of their line-of-sight velocity distributions. We discuss different dark matter density profiles, both cuspy and possessing flat density cores.…
The 3D motions of stars in small galaxies beyond our own are minute and yet they are crucial for our understanding of the nature of gravity and dark matter. Even for the dwarf galaxy Sculptor which is one of the best studied systems and…
Using a newly-developed modeling technique, we present orbit-based dynamical models of the Carina, Draco, Fornax, Sculptor, and Sextans dwarf spheroidal (dSph) galaxies. These models calculate the dark matter profiles non-parametrically…
We present a new approach for chemical evolution modelling, specifically designed to investigate the chemical properties of dwarf galaxies in a full cosmological framework. In particular, we focus on the Sculptor dwarf spheroidal galaxy as…
We analyze four epochs of HST imaging over 18 years for the Draco dwarf spheroidal galaxy. We measure precise proper motions (PMs) for hundreds of stars and combine these with existing line-of-sight (LOS) velocities. This provides the first…
We describe a practical method for constructing axisymmetric two-integral galaxy models (with distribution functions of the form f(E,L_z), in which E is the orbital energy, and L_z is the vertical component of the angular momentum), based…
We investigate the non-spherical density structure of dark halos of the dwarf spheroidal (dSph) galaxies in the Milky Way and Andromeda galaxies based on revised axisymmetric mass models from our previous work. The models we adopt here…
We describe an improved, practical method for constructing galaxy models that match an arbitrary set of observational constraints, without prior assumptions about the phase-space distribution function (DF). Our method is an extension of…
We study the distribution of dark matter in the Draco dwarf spheroidal galaxy by modelling the moments of the line-of-sight velocity distribution of stars obtained from new velocity data of Wilkinson et al. The luminosity distribution is…
Dwarf spheroidal galaxies (dSphs) are prime laboratories for studying dark matter (DM) and the black hole demographics in the low-mass regime. These systems are also often flattened; nevertheless most studies rely on spherical models,…
We forecast parameter uncertainties on the mass profile of a typical Milky Way dwarf spheroidal (dSph) galaxy using the spherical Jeans Equation and Fisher matrix formalism. We show that radial velocity measurements for 1000 individual…
Aims. Recently, both the presence of multiple stellar chemo-kinematic components and rotation in the Sculptor dwarf spheroidal galaxy have been put into question. Therefore, we re-examine the chemo-kinematic properties of this galaxy making…
We introduce a method for measuring the slopes of mass profiles within dwarf spheroidal (dSph) galaxies directly from stellar spectroscopic data and without adopting a dark matter halo model. Our method combines two recent results: 1)…
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…