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相关论文: Sulfur abundances in the Galactic bulge and disk

200 篇论文

Due to their volatile nature, when sulfur and zinc are observed in external galaxies, their determined abundances represent the gas-phase abundances in the interstellar medium. This implies that they can be used as tracers of the chemical…

Lithium abundances are presented for 91 dwarf and subgiant stars in the Galactic bulge. The analysis is based on line synthesis of the 7Li line at 6707 {\AA} in high-resolution spectra obtained during gravitational microlensing events, when…

星系天体物理 · 物理学 2020-02-26 T. Bensby , S. Feltzing , J. C. Yee , J. A. Johnson , A. Gould , M. Asplund , J. Meléndez , S. Lucatello

We compute the chemical evolution of the Galactic bulge in the context of an inside-out model for the formation of the Milky Way. The model contains updated stellar yields from massive stars. The main purpose of the paper is to compare the…

天体物理学 · 物理学 2009-11-13 Silvia K. Ballero , Francesca Matteucci , Livia Origlia , R. Michael Rich

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

Context. The Galactic chemical evolution of sulphur is still under debate. At low metallicities some studies find no correlation between [S/Fe] and [Fe/H], others find [S/Fe] increasing towards lower metallicities, and still others find a…

星系天体物理 · 物理学 2013-12-18 E. Matrozis , N. Ryde , A. K. Dupree

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

Context. Sulfur (S) is one of the lesser-studied $\alpha$-elements. Published investigations of its behavior have so far focused on local stars, and only a few clusters of the Milky Way have been considered to study this topic. We aim to…

星系天体物理 · 物理学 2023-03-22 F. Lucertini , L. Monaco , E. Caffau , A. Mucciarelli , S. Villanova , P. Bonifacio , L. Sbordone

AIMS. Our aims are twofold. First we aim to evaluate the robustness and accuracy of stellar parameters and detailed elemental abundances that can be derived from high-resolution spectroscopic observations of microlensed dwarf and subgiant…

星系天体物理 · 物理学 2015-05-13 T. Bensby , J. A. Johnson , J. Cohen , S. Feltzing , A. Udalski , A. Gould , W. Huang , I. Thompson , J. Simmerer , D. Adén

We present a detailed study of the composition of 20 M giants in the Galactic center with 15 of them confirmed to be in the Nuclear Star Cluster. As a control sample we have also observed 7 M giants in the Milky Way Disk with similar…

Context. The formation and evolution of the Milky Way bulge is still largely an unanswered question. One of the most essential observables needed in its modelling are the metallicity distribution and the trends of the alpha elements as…

星系天体物理 · 物理学 2014-12-10 N. Ryde , M. Schultheis

We have previously studied several elements in 58 selected bulge spheroid stars, based on spectral lines in the H-band. We now derive the abundances of the less-studied elements phosphorus (P; Z=15), sulphur (S; Z=16), and potassium (K;…

In Galactic halo stars, sulphur has been shown to behave like other $\alpha$-elements, but until now, no comprehensive studies have been done on this element in stars of other galaxies. Here, we use high-resolution ESO VLT/FLAMES/GIRAFFE…

This paper investigates the peculiar behaviour of the light even (alpha-elements) and odd atomic number elements in red giants in the galactic bulge, both in terms of the chemical evolution of the bulge, and in terms of possible deep-mixing…

天体物理学 · 物理学 2009-11-11 A. Lecureur , V. Hill , M. Zoccali , B. Barbuy , A. Gomez , D. Minniti , S. Ortolani , A. Renzini

Sulphur (S) is a non-refractory alpha-element that is not locked into dust grains in the interstellar medium. Thus no correction to the measured, interstellar sulphur abundance is needed and it can be readily compared to the S content in…

星系天体物理 · 物理学 2015-05-30 Andreas Koch , Elisabetta Caffau

The present sample of nearby bulgelike dwarf stars has kinematics and metallicities characteristic of a probable inner disk or bulge origin. Ages derived by using isochrones give 10-11 Gyr for these stars and metallicities are in the range…

天体物理学 · 物理学 2009-11-07 Luciana Pompeia , Beatriz Barbuy , Michel Grenon

From a detailed elemental abundance analysis of 102 F and G dwarf stars we present abundance trends in the Galactic thin and thick disks for 14 elements (O, Na, Mg, Al, Si, Ca, Ti, Cr, Fe, Ni, Zn, Y, Ba, and Eu). Stellar parameters and…

天体物理学 · 物理学 2007-05-23 T. Bensby , S. Feltzing , I. Lundström , I. Ilyin

To better understand the origin and evolution of the Milky Way bulge, we have conducted a survey of bulge red giant branch and clump stars using the HERMES spectrograph on the Anglo-Australian Telescope. We targeted ARGOS survey stars with…

星系天体物理 · 物理学 2019-05-01 L. Duong , M. Asplund , D. M. Nataf , K. C. Freeman , M. Ness , L. M. Howes

The chemical abundances measured in stars of the Galactic bulge offer an unique opportunity to test galaxy formation models as well as impose strong constraints on the history of star formation and stellar nucleosynthesis. The aims of this…

星系天体物理 · 物理学 2015-05-20 Gabriele Cescutti , Francesca Matteucci

While the number of stars in the Galactic bulge with detailed chemical abundance measurements is increasingly rapidly, the inner Galactic bulge ( |b| < 2$^\circ$) remains poorly studied, due to heavy interstellar absorption and photometric…

星系天体物理 · 物理学 2018-05-23 G. Nandakumar , N. Ryde , M. Schultheis , B. Thorsbro , H. Jönsson , P. S. Barklem , R. M. Rich , F. Fragkoudi

We present radial velocities and chemical abundances of O, Na, Mg, Al, Si, Ca, Cr, Fe, Co, Ni, and Cu for a sample of 156 red giant branch stars in two Galactic bulge fields centered near (l,b)=(+5.25,-3.02) and (0,-12). The (+5.25,-3.02)…

太阳与恒星天体物理 · 物理学 2015-06-22 Christian I. Johnson , R. Michael Rich , Chiaki Kobayashi , Andrea Kunder , Andreas Koch