相关论文: Constraining Dark Matter Substructure With Gaia Wi…
Massive black holes (MBHs) in galactic nuclei are believed to be surrounded by a high density stellar cluster, whose mass is mostly in hard-to-detect faint stars and compact remnants. Such dark cusps dominate the dynamics near the MBH: a…
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…
Numerical simulations of dark matter collapse and structure formation show that in addition to a large halo surrounding the baryonic component of our galaxy, there also exists a significant number of subhalos that extend hundreds of…
Warm dark matter (WDM) can potentially explain small-scale observations that currently challenge the cold dark matter (CDM) model, as warm particles suppress structure formation due to free-streaming effects. Observing small-scale matter…
The dark matter halo of the Milky Way is predicted to contain a very large number of smaller subhalos. As a result of the dark matter annihilations taking place within such objects, the most nearby and massive subhalos could appear as…
Milky Way (MW) satellites reside within dark matter (DM) subhalos with a broad distribution of circular velocity profiles. This diversity is enhanced with the inclusion of ultra-faint satellites, which seemingly have very high DM densities,…
A decade ago cosmological simulations of increasingly higher resolution were used to demonstrate that virialized regions of Cold Dark Matter (CDM) halos are filled with a multitude of dense, gravitationally-bound clumps. These dark matter…
We present initial results from ``Via Lactea'', the highest resolution simulation to date of Galactic CDM substructure. It follows the formation of a Milky Way-size halo with Mvir=1.8x10^12 Msun in a WMAP 3-year cosmology, using 234 million…
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…
We study how the indirect observation of dark matter substructures in the Milky Way, using recent stellar stream studies, translates into constraints for different dark matter models. Particularly, we use the measured number of dark…
According to the cold dark matter scenario, a large number of dark subhalos should be located within the halo of each Milky-way sized galaxy. One promising possibility for detecting such subhalos is to try to observe their gravitational…
We use Gaia photometry and astrometry to estimate the vertical spatial structure of the Milky Way at the Solar radius, formally accounting for sample incompleteness (the selection function) and parallax measurement uncertainty. Our results…
We employ numerical simulations and simple analytical estimates to argue that dark matter substructures orbiting in the inner regions of the Galaxy can be efficiently destroyed by disk shocking, a dynamical process known to affect globular…
Cold or Warm, the Dark Matter substructure spectrum must extend to objects with masses as low as $10^7 M_\odot$, according to the most recent Lyman-$\alpha$ measurements. Around a Milky Way-like galaxy, more than a thousand of these…
We study the density structures of dark matter subhalos for both cold dark matter and self-interacting dark matter models using high-resolution cosmological $N$-body simulations. We quantify subhalo's central density at 150 pc from the…
Wide binary stars are important for testing alternative models of gravitation in the weak-field regime and understanding the statistical outcomes of dynamical interactions in the general Galactic field. The Gaia mission's collection of…
We provide new constraints on the connection between galaxies in the local universe, identified by the Sloan Digital Sky Survey (SDSS), and dark matter halos and their constituent substructures in the $\Lambda$CDM model using WMAP7…
In cold dark matter cosmological models, structures form and grow by merging of smaller units. Numerical simulations have shown that such merging is incomplete; the inner cores of halos survive and orbit as "subhalos" within their hosts.…
The recent Gaia third data release (DR3) has brought some new exciting data about stellar binaries. It provides new opportunities to fully characterize more stellar systems and contribute to enforce our global knowledge of stars behaviour.…
New data from the $\textit{Gaia}$ satellite, when combined with accurate photometry from the Pan-STARRS survey, allow us to accurately estimate the properties of the GD-1 stream. Here, we analyze the stellar density perturbations in the…