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相关论文: The Gaia-ESO Survey: low-alpha element stars in th…

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We present a detailed abundance analysis of 8 stars selected as extremely metal poor candidates from the Hamburg/ESO Survey (HES). For comparison, we have also analysed 3 extremely metal-poor candidates from the HK survey, and 3 additional…

天体物理学 · 物理学 2009-11-07 Eugenio Carretta , Raffaele Gratton , Judith G. Cohen , Timothy C. Beers , Norbert Christlieb

We aim to constrain the mixing processes in low-mass stars by investigating the behaviour of the Li surface abundance after the main sequence. We take advantage of the data from the sixth internal data release of Gaia-ESO, idr6, and from…

The abundance ratio N/O is a useful tool to study the interplay of galactic processes, e.g. star formation efficiency, time-scale of infall and outflow loading factor We aim to trace log(N/O) versus [Fe/H] in the Milky Way and to compare it…

The Galactic bulge has a bimodal metallicity distribution function: different kinematic, spatial, and, potentially, age distributions characterize the metal-poor and metal-rich components. Despite this observed dichotomy, which argues for…

星系天体物理 · 物理学 2019-05-07 A. Rojas-Arriagada , M. Zoccali , M. Schultheis , A. Recio-Blanco , G. Zasowski , D. Minniti , H. Jönsson , R. E. Cohen

We present emission line strengths, abundances, and element ratios (X/O for Ne, S, Cl, and Ar) for a sample of 38 Galactic disk planetary nebulae (PNe) consisting primarily of Peimbert classification Type I. Spectrophotometry for these PNe…

太阳与恒星天体物理 · 物理学 2015-05-18 J. B. Milingo , K. B. Kwitter , R. B. C. Henry , S. P. Souza

The {\alpha}-element abundances of the globular cluster (GC) and field star populations of galaxies encode information about the formation of each of these components. We use the E-MOSAICS cosmological simulations of ~L* galaxies and their…

NGC 6522 has been the first metal-poor globular cluster identified in the bulge by W. Baade. Despite its importance, very few high resolution abundance analyses of stars in this cluster are available in the literature. The bulge metal-poor…

星系天体物理 · 物理学 2015-05-14 B. Barbuy , M. Zoccali , S. Ortolani , V. Hill , D. Minniti , E. Bica , A. Renzini , A. Gómez

We derive the star formation histories of eight dwarf spheroidal (dSph) Milky Way satellite galaxies from their alpha element abundance patterns. Nearly 3000 stars from our previously published catalog (Paper II) comprise our data set. The…

We present detailed abundance measurements for 45 globular clusters (GCs) in galaxies in (and, in one case, beyond) the Local Group. The measurements are based on new high-resolution integrated-light spectra of GCs in NGC 185, NGC 205, M31,…

星系天体物理 · 物理学 2022-04-20 S. S. Larsen , P. Eitner , E. Magg , M. Bergemann , C. A. S. Moltzer , J. P. Brodie , A. J. Romanowsky , J. Strader

Low-mass, variable, high-velocity stars are interesting study cases for many aspects of Galactic structure and evolution. Until recently, the only known high- or hyper-velocity stars were young stars thought to originate from the Galactic…

太阳与恒星天体物理 · 物理学 2016-05-04 Camilla Juul Hansen , Robert Michael Rich , Andreas Koch , Siyi Xu , Andrea Kunder , Hans-Guenter Ludwig

Globular Clusters (GCs) are natural laboratories where stellar and chemical evolution can be studied in detail. In addition, their chemical patterns and kinematics can tell us wich Galactic structure (Disk, Bulge, Halo or extragalactic) the…

太阳与恒星天体物理 · 物理学 2018-01-10 A. Mura-Guzmán , S. Villanova , C. Muñoz , B. Tang

This paper explores the integrated-light characteristics of the Milky Way (MW) bulge and to what extent they match those of elliptical galaxies in the local universe. We model composite stellar populations with realistic abundance…

星系天体物理 · 物理学 2015-06-22 Baitian Tang , Guy Worthey , A. Bianca Davis

While the Milky Way Nuclear star cluster has been studied extensively, how it formed is uncertain. Studies have shown it contains a solar and supersolar metallicity population that may have formed in-situ, along with a subsolar metallicity…

星系天体物理 · 物理学 2022-02-02 Rory O. Bentley , Tuan Do , Wolfgang Kerzendorf , Devin S. Chu , Zhuo Chen , Quinn Konopacky , Andrea Ghez

Aims. We aim to derive the chemical pattern of the young clusters 25 Orionis and lambda Orionis through homogeneous and accurate measurements of elemental abundances. Methods. We present FLAMES/UVES observations of a sample of 14 K-type…

太阳与恒星天体物理 · 物理学 2015-05-27 K. Biazzo , S. Randich , F. Palla , C. Briceno

The spatial distribution of elemental abundances and their time evolution are among the major constraints to disentangle the scenarios of formation and evolution of the Galaxy. We used the sample of open clusters available in the final…

The Bulge Globular Clusters (GCs) are key tracers of this central ancient component of our Galaxy. It is essential to understand their formation and evolution to study that of the bulge, as well as their relationship with the other Galactic…

太阳与恒星天体物理 · 物理学 2018-12-05 C. Muñoz , D. Geisler , S. Villanova , I. Saviane , C. C. Cortés , B. Dias , R. E. Cohen , F. Mauro , C. Moni Bidin

We present the abundance analysis of 97 nearby metal-poor (-3.3<[Fe/H]<-0.5) stars having kinematics characteristics of the Milky Way (MW) thick disk, inner, and outer stellar halos. The high-resolution, high-signal-to-noise optical spectra…

星系天体物理 · 物理学 2015-06-05 M. N. Ishigaki , M. Chiba , W. Aoki

We report the results of a coherent study of three chemically anomalous metal-poor ([Fe/H] ~ -2) stars. These objects exhibit unusually low abundances of Mg, Si, Ca (alpha-elements) and Sr, Y, and Ba (neutron-capture elements). Our analyses…

The Gaia-ESO Survey (GES) is a large public spectroscopic survey that was carried out using the multi-object FLAMES spectrograph at the Very Large Telescope. The survey provides accurate radial velocities, stellar parameters, and elemental…

We present an overview of the distributions of 11 elemental abundances in the Milky Way's inner regions, as traced by APOGEE stars released as part of SDSS Data Release 14/15 (DR14/DR15), including O, Mg, Si, Ca, Cr, Mn, Co, Ni, Na, Al, and…