相关论文: Co-formation of the Galactic disc and the stellar …
We present a new method to construct fully self-consistent equilibrium models of multi-component disc galaxies similar to the Milky Way. We define distribution functions for the stellar disc and dark halo that depend on phase space position…
The orbital motions of halo stars in the Milky Way reflect the orbital motions of the progenitor systems in which they formed, making it possible to trace the mass-assembly history of the Galaxy. Direct measurement of three-dimensional…
The spin, $\lambda$, of dark matter (DM) halos in cosmological simulations follows a log normal distribution and has little correlation with galaxy observables. As such, there is currently no way to infer the $\lambda$ parameter of…
We present results concerning the internal structure and kinematics of disk galaxies formed in cosmologically motivated simulations. The calculations include dark matter, gas dynamics, radiative cooling, star formation, supernova feedback…
The present day chemical and dynamical properties of the Milky Way bear the imprint of the Galaxy's formation and evolutionary history. One of the most enduring and critical debates surrounding Galactic evolution is that regarding the…
We perform fully self-consistent stellar dynamical simulations of the accretion of a companion ("satellite") galaxy by a large disk galaxy to investigate the interaction between the disk, halo, and satellite components of the system during…
A simple model for the Milky Way halo is presented. It has a flat rotation curve in the inner regions, but the density falls off sharply beyond an outer edge. This truncated, flat rotation curve (TF) model possesses a rich family of simple…
We have simulated the evolution of tidal debris in the Galactic halo in order to guide our ongoing survey to determine the fraction of halo mass accreted via satellite infall. Contrary to naive expectations that the satellite debris will…
Recent work indicates that the nearby Galactic halo is dominated by the debris from a major accretion event. We confirm that result from an analysis of APOGEE-DR14 element abundances and $\textit{Gaia}$-DR2 kinematics of halo stars. We show…
We test the hypothesis that the classical and ultra-faint dwarf spheroidal satellites of the our Galaxy have been the building blocks of the Galactic halo by comparing their [O/Fe] and [Ba/Fe] vs. [Fe/H] patterns with the ones observed in…
We present theoretical calculations for the differential distribution of stellar orbital eccentricity for a sample of solar-neighbour halo stars. Two types of static, spherical gravitational potentials are adopted to define the eccentricity…
We report a new analysis of stellar dynamics in the Galactic centre, based on improved sky and LOS velocities for >100 stars within a few arcsec of SgrA*. Overall the motions do not deviate strongly from isotropy. For 32 stars with all 3…
We find that the relative contribution of satellite galaxies accreted at high redshift to the stellar population of the Milky Way's smooth halo increases with distance, becoming observable relative to the classical smooth halo about 15 kpc…
Previous studies based on the analysis of Gaia DR2 data have revealed that accreted stars, possibly originating from a single progenitor satellite, are a significant component of the halo of our Galaxy, potentially constituting most of the…
We study the vertical structure of a stellar disk obtained from a fully cosmological high-resolution hydrodynamical simulation of the formation of a Milky Way-like galaxy. At the present day, the disk's mean vertical height shows a…
The Hypervelocity Star survey presents the currently largest sample of radial velocity measurements of halo stars out to 80 kpc. We apply spherical Jeans modeling to these data in order to derive the mass profile of the Galaxy. We restrict…
We examine the distributions of eccentricities of orbits within mass distributions like those we see for galaxies and clusters. A comprehensive understanding of these orbital properties is essential to calculate the rates of physical…
We examine the properties and evolution of a simulated polar disc galaxy. This galaxy is comprised of two orthogonal discs, one of which contains old stars (old stellar disc), and the other, containing both younger stars and the cold gas…
The halo spin-spin correlation function, $\eta(r)$, measures how rapidly the strength of the alignments of the spin directions between the neighbor halos change with the separation distance, $r$. The previous model based on the tidal torque…
We review the various techniques used to constrain the Galactic halo mass profile for radii > 20 kpc with particular emphasis on identifying a self-consistent halo model and resolving the apparent discrepancies present in the literature on…