中文
相关论文

相关论文: Oxygen, $\alpha$-element and iron abundance distri…

200 篇论文

We present a compiled catalogue of effective temperatures, surface gravities, iron and magnesium abundances, distances, velocity components, and orbital elements for stars in the solar neighborhood. The atmospheric parameters and iron…

天体物理学 · 物理学 2009-11-10 T. V. Borkova , V. A. Marsakov

Oxygen abundances for a large sample of dwarf and giant stars kinematically selected to be part of the Galactic thin and thick disks have been determined from a non-LTE analysis of the O I triplet lines at 777 nm. The abundance analysis was…

天体物理学 · 物理学 2009-11-11 I. Ramirez , C. Allende Prieto , D. L. Lambert

Metallicities ([Fe/H]) from low resolution spectroscopy obtained with the Very Large Telescope (VLT) are presented for 98 RR Lyrae and 3 short period Cepheids in the bar of the Large Magellanic Cloud. Our metal abundances have typical…

天体物理学 · 物理学 2009-11-10 R. G. Gratton , A. Bragaglia , G. Clementini , E. Carretta , L. Di Fabrizio , M. Maio , E. Taribello , -

The aim of this paper is to characterise the abundance patterns of five iron-peak elements (Mn, Fe, Ni, Cu, and Zn) for which the stellar origin and chemical evolution are still debated. We automatically derived iron peak (Mn, Fe, Ni, Cu,…

太阳与恒星天体物理 · 物理学 2017-10-10 Š. Mikolaitis , P. de Laverny , A. Recio-Blanco , V. Hill , C. C. Worley , M. de Pascale

The location of the Scutum Red-Supergiant (RSG) clusters at the end of the Galactic Bar makes them an excellent probe of the Galaxy's secular evolution; while the clusters themselves are ideal testbeds in which to study the predictions of…

We present spectra obtained with the 10.4 m Gran Telescopio Canarias telescope of 13 Galactic HII regions, most of them of very low ionisation degree. The objects are located along the Galactic disc, with R_G from 5.7 to 16.1 kpc. We…

星系天体物理 · 物理学 2018-05-16 C. Esteban , J. Garcia-Rojas

We examine the \alpha-element abundance ratio, [\alpha/Fe], of 5620 stars, observed by the Sloan Extension for Galactic Understanding and Exploration survey in the region 6 kpc < R < 16 kpc, 0.15 kpc < |Z| < 1.5 kpc, as a function of…

We present preliminary iron abundances and $\alpha$ element (Ca, Mg) abundance ratios for a sample of 22 Red Giant Branch (RGB) Stars in the Sagittarius dwarf spheroidal galaxy (Sgr), selected near the RGB-Tip. The sample is representative…

天体物理学 · 物理学 2007-05-23 Lorenzo Monaco

We explore the elemental abundance features of metal-rich disk stars, highlighting the comparisons made with those of the recently revealed Galactic bulge stars. A similarity between two of the comparisons leads to a new theoretical picture…

天体物理学 · 物理学 2009-11-13 Takuji Tsujimoto

Using a sample of 31 main-sequence OB stars located between galactocentric distances 8.4 - 15.6 kpc, we aim to probe the present-day radial abundance gradients of the Galactic disk. The analysis is based on high-resolution spectra obtained…

太阳与恒星天体物理 · 物理学 2019-05-29 G. A. Braganca , S. Daflon , T. Lanz , K. Cunha , T. Bensby , P. J. McMillan , C. D. Garmany , J. W. Glaspey , M. Borges Fernandes , M. S. Oey , I. Hubeny

I summarize the results of 15 years of research on the surface abundances of stars in globular clusters. Globular-cluster stars afford a unique view of the physical processes that shape the surface abundances of stars on and beyond the…

太阳与恒星天体物理 · 物理学 2021-11-02 A. J. Korn

We derive the abundance of 19 elements in a sample of 64 stars with fundamental parameters very similar to solar, which minimizes the impact of systematic errors in our spectroscopic 1D-LTE differential analysis, using high-resolution…

太阳与恒星天体物理 · 物理学 2009-12-10 I. Ramirez , J. Melendez , M. Asplund

This paper presents the chemical abundance analysis of a sample of 27 red giant stars located in 4 popolous intermediate-age globular clusters in the Large Magellanic Cloud, namely NGC 1651, 1783, 1978 and 2173. This analysis is based on…

天体物理学 · 物理学 2009-11-13 A. Mucciarelli , E. Carretta , L. Origlia , F. R. Ferraro

The circumstellar envelopes (CSEs) of asymptotic giant branch (AGB) stars harbour a rich variety of molecules and are sites of complex chemistry. Our current understanding of the circumstellar chemical processes of carbon-rich AGB stars is…

Using the DR12 public release of APOGEE data, we show that thin and thick disk separate very well in the space defined by [$\alpha$/Fe], [Fe/H] and [C/N]. Thick disk giants have both higher [C/N] and higher [$\alpha$/Fe] than do thin disk…

太阳与恒星天体物理 · 物理学 2015-09-03 T. Masseron , G. Gilmore

We present a detailed elemental abundance study of 90 F and G dwarf, turn-off and subgiant stars in the Galactic bulge. Based on high-resolution spectra acquired during gravitational microlensing events, stellar ages and abundances for 11…

We have re-evaluated empirical expressions for the abundance determination of N, O, Ne, S, Cl, Ar and Fe taking into account the latest atomic data and constructing an appropriate grid of photoionization models with state-of-the art model…

天体物理学 · 物理学 2009-07-28 Y. I. Izotov , G. Stasinska , G. Meynet , N. G. Guseva , T. X. Thuan

We show that the Galactic thick disk reaches at least solar metallicities, and that it experienced strong chemical enrichment during a period of ~3 Gyr, ending around 8-9 Gyr ago. This finding puts further constraints on the relation and…

天体物理学 · 物理学 2010-11-11 T. Bensby , A. R. Zenn , M. S. Oey , S. Feltzing

Recent large-scale infrared surveys have been revealing stellar populations in the inner Galaxy seen through strong interstellar extinction in the disk. In particular, classical Cepheids with their period-luminosity and period-age relations…

The atmospheric parameters and abundances of Mg, Si, Ca, and Ti have been determined for 20 stars using the Gaia DR2 parallaxes, high-resolution spectra, and the non-local thermodynamic equilibrium (non-LTE) line formation modeling. A…

太阳与恒星天体物理 · 物理学 2019-09-04 Lyudmila Mashonkina , Maria Neretina , Tatyana Sitnova , Yuri Pakhomov