相关论文: An ever-present $Gaia$ snail shell triggered by a …
We report the discovery of a young (only 30-40\,Myr) snake-like structure (dubbed a stellar "snake") in the solar neighborhood from {\it Gaia} DR2. The average distance of this structure is about 310\,pc from us. Both the length and width…
The orbits of satellite galaxies encode rich information about their histories. We investigate the orbital dynamics and histories of satellite galaxies around Milky Way (MW)-mass host galaxies using the FIRE-2 cosmological simulations,…
We show that the mass of a dark matter halo can be inferred from the dynamical status of its satellite galaxies. Using 9 dark-matter simulations of halos like the Milky Way (MW), we find that the present-day substructures in each halo…
Identifying the structure of our Galaxy has always been fraught with difficulties, and while modern surveys continue to make progress building a map of the Milky Way, there is still much to understand. The arm and bar features are important…
Relying on the dramatic increase in the number of stars with full 6D phase-space information provided by the Gaia Data Release 3, we discover unambiguous signatures of phase-mixing in the stellar halo around the Sun. We show that for the…
The outer disk of the Milky Way Galaxy is warped and flared. Several mechanisms have been proposed to explain these phenomena, but none have quantitatively reproduced both features. Recent work has demonstrated that the Galactic stellar…
We study numerical simulations of satellite galaxy disruption in a potential resembling that of the Milky Way. Our goal is to assess whether a merger origin for the stellar halo would leave observable fossil structure in the phase-space…
We have performed a high mass and force resolution simulation of an idealized galaxy forming from dissipational collapse of gas embedded in a spherical dark matter halo. The simulation includes star formation and effects of stellar…
We simulate the dynamical and chemical evolution of a dwarf galaxy embedded in a dark matter halo, using a three-dimensional N-body/SPH simulation code combined with stellar population synthesis. The initial condition is adopted in accord…
Context: Deep GALEX UV data show that the extreme outskirts of some spiral galaxies are teeming with star formation. Such young stellar populations evolving so far away from the bulk of their host galaxies challenge our overall…
We present gas and stellar kinematics of a high-resolution zoom-in cosmological chemodynamical simulation, which fortuitously captures the formation and evolution of a star-forming barred spiral galaxy, from redshift $z\sim3$ to $z\sim2$ at…
We study the formation of the Milky Way's halo in a $\Lambda$CDM cosmology by scaling down a high resolution simulation of the formation of a cluster of galaxies. We determine how much phase-space substructure is left over from the objects…
The formation of our Milky Way can be parsed qualitatively into different phases that resulted in its structurally different stellar populations: the halo and the disk components. Revealing a quantitative overall picture of the Galactic…
We analyze the formation and evolution of the stellar components in "Eris", a 120 pc-resolution cosmological hydrodynamic simulation of a late-type spiral galaxy. The simulation includes the effects of a uniform UV background, a…
We use accurate estimates of aluminium abundance provided as part of the APOGEE Data Release 17 and Gaia Early Data Release 3 astrometry to select a highly pure sample of stars with metallicity $-1.5\lesssim {\rm [Fe/H]}\lesssim 0.5$ born…
We analyse the dynamical properties of substructures in a high-resolution dark matter simulation of the formation of a Milky Way-like halo in a $\Lambda$CDM cosmology. Our goal is to shed light on the dynamical peculiarities of the Milky…
Context. The physical processes driving the formation of Galactic spiral arms are still under debate. Studies using open clusters favour the description of the Milky Way spiral arms as long-lived structures following the classical density…
The GAIA Observatory, ESA's Cornerstone 6 mission, addresses the origin and evolution of our Galaxy, and a host of other scientific challenges. GAIA will provide unprecedented positional and radial velocity measurements with the accuracies…
The characteristics of Gaia catalogues, such as trigonometric parallaxes and proper motions of stars, are discussed. Radial velocities of stars are also important for studying spatial motions. The most important results of the kinematics…
We investigate what the proposed ESA astrometric satellite GAIA will reveal by observing the halo of the Milky Way. Specifically, we look for halo streams which are the signatures left by the merging/accretion events experienced by a…