相关论文: Willman 1 - A Galactic Satellite at 40 kpc With Mu…
The Via Lactea simulation of the dark matter halo of the Milky Way predicts the existence of many thousands of bound subhalos distributed approximately with equal mass per decade of mass. Here we show that: a) a similar steeply rising…
We report the discovery of a new ultra-faint dwarf satellite companion of the Milky Way based on the early survey data from the Hyper Suprime-Cam Subaru Strategic Program. This new satellite, Virgo I, which is located in the constellation…
This study presents a tomographic survey of a subset of the outer halo (10-40 kpc) drawn from the Sloan Digital Sky Survey Data Release 6. Halo substructure on spatial scales of $>3$ degrees is revealed as an excess in the local density of…
We report on the discovery of the most distant Milky Way (MW) stars known to date: ULAS J001535.72$+$015549.6 and ULAS J074417.48$+$253233.0. These stars were selected as M giant candidates based on their infrared and optical colors and…
The spatial distribution of Milky Way (MW) subhaloes provides an important set of observables for testing cosmological models. These include the radial distribution of luminous satellites, planar configurations, and the abundance of dark…
The spatial distributions of the most recently discovered ultra faint dwarf satellites around the Milky Way and the Andromeda galaxy are compared to the previously reported discs-of-satellites (DoS) of their host galaxies. In our…
Joint analyses of small-scale cosmological structure probes are relatively unexplored and promise to advance measurements of microphysical dark matter properties using heterogeneous data. Here, we present a multidimensional analysis of dark…
Numerical simulations of Milky-Way size Cold Dark Matter (CDM) halos predict a steeply rising mass function of small dark matter subhalos and a substructure count that greatly outnumbers the observed satellites of the Milky Way. Several…
Using high-resolution collisionless N-body simulations we study the properties of tidal tails formed in the immediate vicinity of a two-component dwarf galaxy evolving in a static potential of the Milky Way (MW). The stellar component of…
We report the identification of SDSS J121929.45+471522.8 as the third apparently isolated magnetic (B~18.5+/-1.0,MG) white dwarf exhibiting Zeeman-split Balmer emission lines. The star shows coherent variability at optical wavelengths with…
The Milky Way (MW) dwarf system presents two exceptional features, namely it forms a thick plane called the Vast Polar Structure (VPOS), and the two biggest dwarves, the Magellanic Clouds (MCs), are irregular galaxies that are almost never…
We present the first results from SWARMS (Sloan White dwArf Radial velocity data Mining Survey), an ongoing project to identify compact white dwarf (WD) binaries in the spectroscopic catalog of the Sloan Digital Sky Survey. The first object…
We present multiwavelength, multi-telescope, ground-based follow-up photometry of the white dwarf WD 1145+017, that has recently been suggested to be orbited by up to six or more, short-period, low-mass, disintegrating planetesimals. We…
We compare the structure and kinematics of the 11 known satellites of the Milky Way with high resolution simulations of the formation of its dark halo in a LambdaCDM universe. In contrast to earlier work, we find excellent agreement. The…
We combine our Hubble Space Telescope measurement of the proper motion of the Leo I dwarf spheroidal galaxy (presented in a companion paper) with the highest resolution numerical simulations of Galaxy-size dark matter halos in existence to…
We present the results of our analysis of the geometrical tidal tail characteristics for nearby and distant interacting galaxies. The sample includes more than two hundred nearby galaxies and about seven hundred distant ones. The distant…
We study the abundance of satellites akin to the brightest, classical dwarf spheroidals around galaxies similar in magnitude and isolation to the Milky Way and M31 in the Sloan Digital Sky Survey. From a combination of photometric and…
We investigate the population of bright satellites ($M_{*} \geq 10^{5} \mathrm{M}_{\odot}$) of haloes of mass comparable to that of the Milky Way in cosmological simulations in which the dark matter (DM) is either cold, warm or…
The Milky Way's (MW) satellite population is a powerful probe of warm dark matter (WDM) models as the abundance of small substructures is very sensitive to the properties of the WDM particle. However, only a partial census of the MW's…
We have presented 309 new white-dwarf (WD) + main-sequence (MS) star binaries identified from the Sloan Digital Sky Survey (SDSS) Tenth Data Release (DR10). The majority of them consist of a white dwarf and a low-mass secondary (typically M…