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相关论文: On the Origin of Sulfur

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Sulfur abundances have been determined for ten stars to resolve a debate in the literature on the Galactic chemical evolution of sulfur in the halo phase of the Milky Way. Our analysis is based on observations of the S I lines at 9212.9,…

天体物理学 · 物理学 2009-11-10 N. Ryde , D. L. Lambert

We investigate the debated "sulphur discrepancy" found among metal-poor stars of the Galactic halo with [Fe/H] < -2. This discrepancy stems in part from the use of two different sets of sulphur lines, the very weak triplet at 8694-95 A and…

天体物理学 · 物理学 2016-08-30 Andreas J. Korn , Nils Ryde

From equivalent widths of the SI lines at 8694 A, Israelian & Rebolo (2001) and Takada-Hidai et al. (2002) have derived a surprisingly high sulphur-to-iron ratio ([S/Fe] = 0.5 to 0.7) in six halo stars with [Fe/H] ~ -2.0 suggesting perhaps…

天体物理学 · 物理学 2007-05-23 P. E. Nissen , Y. Q. Chen , M. Asplund , M. Pettini

We have obtained high-resolution high signal-to-noise spectra of the SI near-infrared doublet at 8694 A in eight metal-poor stars with metallicities in the range -0.6 <[Fe/H]< -3.0. Elemental sulphur abundances were derived for six targets…

天体物理学 · 物理学 2009-11-06 Garik Israelian , Rafael Rebolo

High resolution UVES spectra of 40 main-sequence stars with -3.3 < [Fe/H] < -1.0 are used to derive S, Fe and Zn abundances from lines in the 400 - 950 nm region. For one star we also present novel observations of the SI triplet at 1.046…

天体物理学 · 物理学 2009-11-13 P. E. Nissen , C. Akerman , M. Asplund , D. Fabbian , F. Kerber , H. U. Kaufl , M. Pettini

High resolution spectra of 34 halo population dwarf and subgiant stars have been obtained with VLT/UVES and used to derive sulphur abundances from the 8694.0, 8694.6 A and 9212.9, 9237.5 A SI lines. In addition, iron abundances have been…

天体物理学 · 物理学 2009-11-10 P. E. Nissen , Y. Q. Chen , M. Asplund , M. Pettini

Sulphur is an important, volatile alpha element but its role in the Galactic chemical evolution is still uncertain. We derive the S abundances in RGB stars in three Galactic globular clusters (GC) that cover a wide metallicity range…

星系天体物理 · 物理学 2015-04-29 Nikolay Kacharov , Andreas Koch , Elisabetta Caffau , Luca Sbordone

In an attempt of clarifying the [S/Fe] behavior with the run of [Fe/H] in the metal-poor regime which has been a matter of debate, an extensive non-LTE analysis of near-IR S I triplet lines (multiplet 3) at 1.046 micron was carried out for…

太阳与恒星天体物理 · 物理学 2015-05-19 Yoichi Takeda , Masahide Takada-Hidai

context : Unlike silicon and calcium, sulphur is an alpha-element which does not form dust. Some of the available observations of the evolution of sulphur with metallicity indicate an increased scatter of sulphur to iron ratios at low…

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

Sulfur is important: the site of its formation is uncertain, and at very low metallicity the trend of [S/Fe] against [Fe/H] is controversial. Below [Fe/H]=-2.0, [S/Fe] remains constant or it decreases with [Fe/H], depending on the author…

It is still debated whether or not the Galactic chemical evolution of sulphur in the halo followed the constant or flat trend with [Fe/H], ascribed to the result of explosive nucleosynthesis in type II SNe. The aim of this study is to try…

星系天体物理 · 物理学 2015-05-27 H. Jönsson , N. Ryde , P. E. Nissen , R. Collet , K. Eriksson , M. Asplund , B. Gustafsson

We have derived abundances of O, Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Fe, Ni and Ba for 43 metal-poor field stars in the solar neighbourhood with iron abundances [Fe/H] ranging from -0.4 to -3.0. Total abundance errors are estimated to about…

Sulphur is a volatile alpha-element which is not locked into dust grains in the interstellar medium (ISM). Hence, its abundance does not need to be corrected for dust depletion when comparing the ISM to the stellar atmospheres. The…

星系天体物理 · 物理学 2015-05-18 Elisabetta Caffau , Luca Sbordone , Hans-Günter Ludwig , Piercarlo Bonifacio , Monique Spite

We investigate sulphur abundance in 74 Galactic stars by using high resolution spectra obtained at ESO VLT and NTT telescopes. For the first time the abundances are derived, where possible, from three optical multiplets: Mult. 1, 6, and 8.…

天体物理学 · 物理学 2009-11-11 E. Caffau , P. Bonifacio , R. Faraggiana , P. Francois , R. G. Gratton , M. Barbieri

Context. Elemental abundances are of prime importance to help us reconstruct the origin and evolution of stars and galaxies in our Universe. Sulfur abundances have not been as heavily studied as other elements, so some details regarding its…

太阳与恒星天体物理 · 物理学 2020-02-26 Ana Rita Costa Silva , Elisa Delgado Mena , Maria Tsantaki

Sulfur is a volatile chemical element that plays an important role in tracing the chemical evolution of galaxies. However, its nucleosynthesis origin and abundance variations are still unclear. The goal of the present article is to…

The failure of S and O abundances in most planetary nebulae to display the same strong direct correlation that is observed in extragalactic H II regions represents one of the most perplexing problems in the area of PN abundances today.…

天体物理学 · 物理学 2009-11-11 R. B. C. Henry , J. N. Skinner , K. B. Kwitter , M. B. Milingo

Context. The measurement of $\alpha$-elements abundances provides a powerful tool to put constraints on chemical evolution and star formation history of galaxies. The majority of studies on the $\alpha$-element Sulfur (S) are focused on…

星系天体物理 · 物理学 2021-12-22 F. Lucertini , L. Monaco , E. Caffau , P. Bonifacio , A. Mucciarelli

LTE and NLTE abundances of sulfur in 6 metal-poor giants and 61 dwarfs (62 dwarfs, including the Sun) were explored in the range of -3 \lsim [Fe/H] \lsim $+0.5$ using high-resolution, high signal-to-noise ratio spectra of the \SI 8693.9 \AA…

天体物理学 · 物理学 2009-11-06 M. Takada-Hidai , Y. Takeda , S. Sato , S. Honda , K. Sadakane , S. Kawanomoto , W. L. W. Sargent , L. Lu , T. A. Barlow
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