中文
相关论文

相关论文: Cosmic variance in [O/Fe] in the Galactic disk

200 篇论文

The space velocities and Galactic orbital elements of stars calculated from the currently available high-accuracy observations in our summary catalog of spectroscopic magnesium abundances in dwarfs and subgiants in the solar neighborhood…

天体物理学 · 物理学 2015-06-24 V. A. Marsakov , T. V. Borkova

We present the first results from MMT and Keck spectroscopy for a large sample of $0.1\leq z\leq1$ emission-line galaxies selected from our narrow-band imaging in the Subaru Deep Field. We measured the weak [OIII]$\lambda$4363 emission line…

星系天体物理 · 物理学 2016-09-22 Chun Ly , Matthew A. Malkan , Jane Rigby , Tohru Nagao

The Sloan Digital Sky Survey III/Apache Point Observatory Galactic Evolution Experiment (SDSS-III/APOGEE) is a large-scale spectroscopic survey of Galactic stars and star clusters. The SDSS-III/APOGEE survey is designed to produce high-S/N,…

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…

星系天体物理 · 物理学 2022-05-25 Vasily Belokurov , Andrey Kravtsov

We discuss oxygen and iron abundance patterns in K and M red-giant members of the Galactic bulge and in the young and massive M-type stars inhabiting the very center of the Milky Way. The abundance results from the different bulge studies…

天体物理学 · 物理学 2009-11-13 K. Cunha , V. Smith , K. Sellgren , R. Blum , S. Ramirez , D. Terndrup

We present results of a detailed chemical analysis performed on 23 main-sequence turnoff stars having -3.4<=[Fe/H]<=-2.2, a sample selected to be highly homogeneous in T_eff and log(g). We investigate the efficiency of mixing in the early…

天体物理学 · 物理学 2009-11-10 E. Arnone , S. G. Ryan , D. Argast , J. E. Norris , T. C. Beers

The spatial distribution of metals reflects, and can be used to constrain, the processes of chemical enrichment and mixing. Using PHANGS-MUSE optical integral field spectroscopy, we measure the gas phase oxygen abundances (metallicities)…

Using two alternative [O/H]-[Fe/H] dependences, the empirical oxygen abundance distribution (EGD) is deduced from two different samples of old objects, available in the literature. Under the assumption that each distribution (with the…

天体物理学 · 物理学 2008-11-26 R. Caimmi

Inhomogeneous chemical evolution models of galaxies which try to reproduce the scatter seen in element-to-iron ratios of metal-poor halo stars are heavily dependent on theoretical nucleosynthesis yields of core-collapse supernovae. Hence…

天体物理学 · 物理学 2009-11-06 D. Argast , M. Samland , F. -K. Thielemann , O. E. Gerhard

The chemical evolution of fluorine is investigated in a sample of Milky Way red giantstars that span a significant range in metallicity from [Fe/H] $\sim$ -1.3 to 0.0 dex. Fluorine abundances are derived from vibration-rotation lines of HF…

太阳与恒星天体物理 · 物理学 2019-11-11 Rafael Guerço , Katia Cunha , Verne V. Smith , Christian R. Hayes , Carlos Abia , David L. Lambert , Henrik Jönsson , Nils Ryde

CONTEXT: [ABRIDGED]. For the Milky Way bulge, there are currently essentially no measurements of carbon in un-evolved stars, hampering our abilities to properly compare Galactic chemical evolution models to observational data for this still…

星系天体物理 · 物理学 2021-12-01 T. Bensby , A. Gould , M. Asplund , S. Feltzing , J. Meléndez , J. A. Johnson , S. Lucatello , A. Udalski , J. C. Yee

Carbon and oxygen abundances in F and G main-sequence stars ranging in metallicity from [Fe/H] = -1.6 to +0.5 are determined from a non-LTE analysis of CI and OI atomic lines in high-resolution spectra. Both C and O are good tracers of…

星系天体物理 · 物理学 2015-06-16 Poul E. Nissen , William J. Schuster

Chemical tagging of stars based on their similar compositions can offer new insights about the star formation and dynamical history of the Milky Way. We investigate the feasibility of identifying groups of stars in chemical space by…

星系天体物理 · 物理学 2018-02-20 Natalie Price-Jones , Jo Bovy

We characterize the 3-D spatial variations of [Fe/H], [Mg/H], and [Mg/Fe] in stars at the time of their formation, across 11 simulated Milky Way (MW)- and M31-mass galaxies in the FIRE-2 simulations, to inform initial conditions for…

星系天体物理 · 物理学 2022-06-22 Matthew A. Bellardini , Andrew Wetzel , Sarah R. Loebman , Jeremy Bailin

Atmospheric parameters and oxygen abundances of 825 nearby FGK stars are derived using high-quality spectra and a non-LTE analysis of the 777 nm O I triplet lines. We assign a kinematic probability for the stars to be thin-disk (P1),…

太阳与恒星天体物理 · 物理学 2015-06-12 I. Ramirez , C. Allende Prieto , D. L. Lambert

The distribution of stellar abundances along the Galactic disk is an important constraint for models of chemical evolution and Galaxy formation. In this study we derive radial gradients of C, N, O, Mg, Al, Si, as well as S, from abundance…

天体物理学 · 物理学 2009-11-10 Simone Daflon , Katia Cunha

It is well established that the chemical structure of the Milky Way exhibits a bimodality with respect to the $\alpha$-enhancement of stars at a given [Fe/H]. This has been studied largely based on a bulk $\alpha$ abundance, computed as a…

星系天体物理 · 物理学 2019-09-20 Kirsten Blancato , Melissa Ness , Kathryn V. Johnston , Jan Rybizki , Megan Bedell

We present detailed spectroscopic analysis of nitrogen abundances in 31 unevolved metal-poor stars analysed by spectral synthesis of the near-UV NH band at 3360 A observed at high resolution with various telescopes. We found that [N/Fe]…

天体物理学 · 物理学 2009-11-10 G. Israelian , A. Ecuvillon , R. Rebolo , R. Garcia Lopez , P. Bonifacio , P. Molaro

First results from a study into the abundance trends of oxygen in the Galactic thin and thick disks are presented. Oxygen abundances for 63 nearby F and G dwarf stars, based on very high resolution spectra ($R\sim215 000$) and high…

天体物理学 · 物理学 2010-04-28 T. Bensby , S. Feltzing , I. Lundström

Context: Classical Cepheids can be adopted to trace the chemical evolution of the Galactic disk since their distances can be estimated with very high accuracy. Aims: Homogeneous iron abundance measurements for 33 Galactic Cepheids located…

天体物理学 · 物理学 2009-11-13 B. Lemasle , P. Francois , A. Piersimoni , S. Pedicelli , G. Bono , C. D. Laney , F. Primas , M. Romaniello