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Related papers: The age structure of the Milky Way's halo

200 papers

We combine asteroseismology, optical high-resolution spectroscopy, and kinematic analysis for 26 halo red giant branch stars in the \textit{Kepler} field in the range of $-2.5<[\mathrm{{Fe}/{H}}]<-0.6$. After applying theoretically…

We present a panoramic map of the entire Milky Way halo north of dec~-30 degrees (~30,000 deg^2), constructed by applying the matched-filter technique to the Pan-STARRS1 3Pi Survey dataset. Using single-epoch photometry reaching to g~22, we…

Stellar ages are a crucial component to studying the evolution of the Milky Way. Using Gaia DR2 distance estimates, it is now possible to estimate stellar ages for a larger volume of evolved stars through isochrone matching. This work…

We investigated the habitability of the Milky Way, making use of recent observational analysis on the prevalence of Earth-sized planets, in order to estimate where and when potentially habitable star systems may have formed over the course…

Astrophysics of Galaxies · Physics 2015-09-10 Daniel Legassick

Modeling the Milky Way stellar halo requires well-determined density and velocity anisotropy profiles. However, it has been challenging to gather a large sample of stars with six-dimensional data that extend beyond 40 kpc to map the outer…

Recent observational programmes are providing a global view of the Milky Way bulge that serves as template for detailed comparison with models and extragalactic bulges. A number of surveys (i.e. VVV, GIBS, GES, ARGOS, BRAVA, APOGEE) are…

Astrophysics of Galaxies · Physics 2019-03-27 F. Surot , E. Valenti , S. L. Hidalgo , M. Zoccali , E. Sökmen , M. Rejkuba , D. Minniti , O. A. Gonzalez , S. Cassisi , A. Renzini , A. Weiss

We report the results of a systematic photometric survey of the peripheral regions of a sample of fourteen globular clusters in the outer halo of the Milky Way at distances d_GC>25 kpc from the Galactic centre. The survey is aimed at…

We describe a major survey of the Milky Way halo designed to test for kinematic substructure caused by destruction of accreted satellites. We use the Washington photometric system to identify halo stars efficiently for spectroscopic…

Near- and mid-IR survey data from DENIS and ISOGAL are used to investigate the structure and formation history of the inner 10 degree (1.4 kpc) of the Milky Way galaxy. Synthetic bolometric corrections and extinction coefficients in the…

Although Blue Horizontal Branch (BHB) stars are commonly used to trace halo substructure, the stars bluer than (g-r)<-0.3 are ignored due to the difficulty in determining their absolute magnitudes. The blue extention of the horizontal…

Astrophysics of Galaxies · Physics 2021-04-07 Robert Gryncewicz , Heidi Jo Newberg , Charles Martin , Thomas Donlon , Paul M. Amy

About 25% of the Milky Way globular clusters (GCs) exhibit unusually extended color distribution of stars in the horizontal-branch (HB) phase. This phenomenon is now best understood as due to the presence of helium enhanced second…

Astrophysics · Physics 2009-11-13 Young-Wook Lee , Hansung B. Gim , Dana I. Casetti-Dinescu

The orbital motions of halo stars in the Milky Way reflect the orbital motions of the progenitor systems in which they formed, making it possible to trace the mass-assembly history of the Galaxy. Direct measurement of three-dimensional…

Astrophysics of Galaxies · Physics 2015-06-12 Kohei Hattori , Yuzuru Yoshii , Timothy C. Beers , Daniela Carollo , Young Sun Lee

The age distribution of the open cluster system is a key piece of information to decipher the star formation history of the Milky Way disk. Recently, a remarkable earlier drop of its older end was found, which caught our attention.…

Astrophysics of Galaxies · Physics 2023-07-18 Andrés E. Piatti

We study the age and metallicity distribution function (MDF) of metal-poor stars in the Milky Way halo as a function of galactocentric radius by combining N-body simulations and semi-analytical methods. We find that the oldest stars…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 S. Salvadori , A. Ferrara , R. Schneider , E. Scannapieco , D. Kawata

The Milky Way in-situ halo, also known as the Splash, consists of old (Age $>$ 10 Gyr), metal-rich ([Fe/H] $> -0.7$), high-$\alpha$ stars, i.e., thick disk-like chemistry, on halo-like orbits (eccentricity > 0.6). Its origin is linked to…

Theoretical integrated broad-band colors ranging from far-UV to near-IR have been computed for old stellar systems from our evolutionary population synthesis code. These models take into account, for the first time, the detailed systematic…

Astrophysics · Physics 2009-11-07 Hyun-chul Lee , Young-Wook Lee , Brad K. Gibson

We offer a new way to look at the Large Magellanic Cloud through stellar mono-abundance and mono-age-mono-abundance maps. These maps are based on $\gtrsim 500\,000$ member stars with photo-spectroscopic [M/H] and age estimates from Gaia DR3…

Astrophysics of Galaxies · Physics 2024-03-14 Neige Frankel , Rene Andrae , Hans-Walter Rix , Joshua Povick , Vedant Chandra

We use a series of high-resolution N-body simulations of a `Milky-Way' halo, coupled to semi-analytic techniques, to study the formation of our own Galaxy and of its stellar halo. Our model Milky Way galaxy is a relatively young system…

Astrophysics · Physics 2015-05-13 Gabriella De Lucia , Amina Helmi

We use Gaia DR2 astrometric and photometric data, published radial velocities and MESA models to infer distances, orbits, surface gravities, and effective temperatures for all ultra metal-poor stars ($\FeH<-4.0$ dex) available in the…

We use Sloan Digital Sky Survey (SDSS) Data Release 5 (DR5) u,g,r,i,z photometry to study Milky Way halo substructure in the area around the North Galactic Cap. A simple color cut (g-r < 0.4) reveals the tidal stream of the Sagittarius…