Results 21 to 30 of about 43,519 (315)
The Astrophysical Journal, 2023 Orbital characteristics based on Gaia Early Data Release 3 astrometric parameters are analyzed for ∼1700 r -process-enhanced (RPE; [Eu/Fe] > +0.3) metal-poor stars ([Fe/H] ≤ −0.8) compiled from the R -Process Alliance, the GALactic Archaeology with ...
Derek Shank +10 more
doaj +1 more source
Dynamically constraining the length of the Milky way bar
Monthly Notices of the Royal Astronomical Society, 2023 ABSTRACT We present a novel method for constraining the length of the Galactic bar using 6D phase-space information to directly integrate orbits. We define a pseudo-length for the Galactic bar, named RFreq, based on the maximal extent of trapped bar orbits.
Madeline Lucey +7 more
openaire +2 more sources
The Astrophysical Journal, 2023 We continue our series of papers on phase-space distributions of stars in the Milky Way based on photometrically derived metallicities and Gaia astrometry, with a focus on the halo−disk interface in the local volume.
Deokkeun An +3 more
doaj +1 more source
Chemical and Dynamical History of the Milky Way [PDF]
Symposium - International Astronomical Union, 1996 F-G dwarf stars of different metallicity are used as tracers of chemical and dynamical history of the Galaxy. Observed ratios of element abundances “[X/Fe] versus [Fe/H]” (where “X” is a some of chemical element) are compared with theoretical ones and allow us to make the choice between models (or parameters of theoretical models) of the Galaxy ...
N. A. Sakhibullin +4 more
openaire +2 more sources
ACTION-BASED DYNAMICAL MODELING FOR THE MILKY WAY DISK [PDF]
The Astrophysical Journal, 2016 ABSTRACT We present RoadMapping, a full-likelihood dynamical modeling machinery that aims to recover the Milky Way’s (MW) gravitational potential from large samples of stars in the Galactic disk. RoadMapping models the observed positions and velocities of stars with a parameterized, three-integral distribution function (DF) in a ...
Wilma H. Trick, Jo Bovy, Hans-Walter Rix
openaire +8 more sources
The Astrophysical Journal, 2023 In the Λ-Cold Dark Matter model of the universe, galaxies form in part through accreting satellite systems. Previous works have built an understanding of the signatures of these processes contained within galactic stellar halos.
Danny Horta +9 more
doaj +1 more source
Overview of the DESI Milky Way Survey
The Astrophysical Journal, 2023 We describe the Milky Way Survey (MWS) that will be undertaken with the Dark Energy Spectroscopic Instrument (DESI) on the Mayall 4 m telescope at the Kitt Peak National Observatory.
Andrew P. Cooper +64 more
doaj +1 more source
The Rapid Onset of Stellar Bars in the Baryon-dominated Centers of Disk Galaxies
The Astrophysical Journal, 2023 Recent observations of high-redshift galactic disks ( z ≈ 1–3) show a strong negative trend in the dark-matter (DM) fraction f _DM with increasing baryon surface density.
Joss Bland-Hawthorn +3 more
doaj +1 more source
Stellar Bars in Isolated Gas-rich Spiral Galaxies Do Not Slow Down
The Astrophysical Journal, 2023 Elongated bar-like features are ubiquitous in galaxies, occurring at the centers of approximately two-thirds of spiral disks in the nearby Universe. Due to gravitational interactions between the bar and the other components of galaxies, it is expected ...
Angus Beane +8 more
doaj +1 more source
Dynamical Model of the Milky Way Using APOGEE and Gaia Data [PDF]
The Astrophysical Journal, 2021 Abstract We construct a dynamical model of the Milky Way disk from a data set that combines Gaia EDR3 and APOGEE data throughout galactocentric radii in the range 5.0 kpc ≤ R ≤ 19.5 kpc. We make use of the spherically aligned Jeans anisotropic method to model the stellar velocities and their velocity dispersions.
Maria Selina Nitschai +4 more
openaire +4 more sources