Related papers: Velocity Dispersion of the GD-1 Stellar Stream
We use velocity and metallicity information from SDSS and SEGUE stellar spectroscopy to fit an orbit to the narrow $63^\circ$ stellar stream of Grillmair and Dionatos. The stars in the stream have a retrograde orbit with eccentricity $e =…
We analyze the Illustris-1 hydrodynamical cosmological simulation to explore the stellar velocity dispersion of quiescent galaxies as an observational probe of dark matter halo velocity dispersion and mass. Stellar velocity dispersion is…
Thin stellar streams originating from globular clusters are among the most sensitive tracers of low-mass dark-matter subhalos. Joint analysis of the entire population of stellar streams will place the most robust constraints on the…
We present the results of a spectroscopic survey performed in the outskirts of the globular cluster NGC1851 with VIMOS@VLT. The radial velocities of 107 stars in a region between 12' and 33' around the cluster have been derived. We clearly…
Context. The Sagittarius (Sgr) dwarf spheroidal galaxy is currently being disrupted under the strain of the Milky Way. A reliable reconstruction of Sgr star formation history can only be obtained by combining core and stream information.…
The recently discovered C-19 stellar stream is a collection of kinematically associated metal-poor stars in the halo of the Milky Way lacking an obvious progenitor. The stream spans an arc of ~15 degrees in the sky, and orbit-fitting…
We study the effect of dynamical friction on globular clusters and on the stars evaporated from the globular clusters (stellar streams) moving in a galactic halo. Due to dynamical friction, the position of a globular cluster (GC) as a…
In this study, we investigate the chemical properties of the GD-1 stream using cross-matched, data-driven elemental abundances. The results reveal no clear $\alpha$-knee in the [Mg/Fe]-[Fe/H] plane, and strong abundance consistency between…
A sufficiently extended satellite in the tidal field of a host galaxy loses mass to create nearly symmetric leading and trailing tidal streams. We study the case in which tidal heating drives mass loss from a low mass satellite. The stream…
Velocity dispersion ($\sigma$) in stellar streams from globular clusters (GCs) is sensitive to heating by Galactic substructure, including dark matter (DM) subhalos. Recent studies have compared $\sigma$ in observed and modeled streams to…
Recent years have seen the discovery of an ever growing number of stellar debris streams and clouds. These structures are typically detected as extended and often curvilinear overdensities of metal-poor stars that stand out from the…
Globular cluster (GC) streams, debris of stars that tidally stripped from their progenitor GCs, have densities that correlate positively with the GC mass loss rate. In this work, we employ a novel particle spray algorithm that can…
Traditional studies on stellar streams typically involve phenomenological $\Lambda$CDM halos or ad hoc dark matter (DM) profiles with different degrees of triaxiality, which preclude to gain insights into the nature and mass of the DM…
We present the first detailed chemical abundances for seven GD-1 stream stars from Subaru/HDS spectroscopy. Atmospheric parameters were derived via color calibrations ($T\rm_{eff}$) and iterative spectroscopic analysis. LTE abundances for…
We explore the phase-space structure of nearby halo stars identified kinematically from Gaia DR2 data. We focus on their distribution in velocity and in "integrals of motion" space as well as on their photometric properties. Our sample of…
An analysis of large-area CO J=3-2 maps from the James Clerk Maxwell Telescope for 12 nearby spiral galaxies reveals low velocity dispersions in the molecular component of the interstellar medium. The three lowest luminosity galaxies show a…
We present a study of the kinematics of 101 stars observed with VIMOS around Whiting1, a globular cluster embedded in the Sagittarius tidal stream. The obtained velocity distribution shows the presence of two wraps of that halo substructure…
We perform numerical simulations of a stellar galactic disk with initial conditions chosen to represent an unrelaxed population which might have been left following a merger. Stars are unevenly distributed in radial action angle, though the…
NGC 3311, the central galaxy of the Hydra I cluster, shows signatures of recent infall of satellite galaxies from the cluster environment. Previous work has shown that the line-of-sight velocity dispersion of the stars and globular clusters…
We detect a tidal stream generated by the globular cluster NGC 3201 extending over ~140 degrees on the sky, using the Gaia DR2 data, with the maximum likelihood method we presented previously to study the M68 tidal stream. Most of the…