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Related papers: Sulfur Abundances in the Orion Association B Stars

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We present non-LTE oxygen abundances for a sample of B stars in the Orion association. The abundance calculations included non-LTE line formation and used fully blanketed non-LTE model atmospheres. The stellar parameters were the same as…

Solar and Stellar Astrophysics · Physics 2015-05-30 K. Cunha , I. Hubeny , T. Lanz

Argon abundances have been derived for a sample of B main-sequence stars in the Orion association. The abundance calculations are based on NLTE metal line-blanketed model atmospheres calculated with the NLTE code TLUSTY and an updated and…

Astrophysics · Physics 2008-05-21 Thierry Lanz , Katia Cunha , Jon Holtzman , Ivan Hubeny

We report on non-LTE Ne abundances for a sample of B-type stellar members of the Orion Association. The abundances were derived by means of non-LTE fully metal-blanketed model atmospheres and extensive model atoms with updated atomic data.…

Astrophysics · Physics 2009-11-11 Katia Cunha , Ivan Hubeny , Thierry Lanz

The boron abundances for two young solar-type members of the Orion association, BD -6 1250 and HD 294297, are derived from HST STIS spectra of the B I transition at 2496.771 A. The best-fit boron abundances for the target stars are 0.13 and…

Astrophysics · Physics 2009-10-31 K. Cunha , V. Smith , E. Parizot , D. Lambert

Non-LTE abundances of magnesium, aluminum and sulfur are derived for a sample of 23 low-v \sin i stars belonging to six northern OB associations of the Galactic disk within 1 kpc of the Sun. The abundances are obtained from the fitting of…

Astrophysics · Physics 2009-11-07 S. Daflon , K. Cunha , V. V. Smith , K. Butler

We have compiled a large sample of O, Ne, S, Cl, and Ar abundances which have been determined for 85 galactic planetary nebulae in a consistent and homogeneous manner using spectra extending from 3600-9600 Angstroms. Sulfur abundances have…

Astrophysics · Physics 2009-11-10 R. B. C. Henry , K. B. Kwitter , Bruce Balick

The abundances of chemical elements and their depletion factors are essential parameters for understanding the composition of the gas and dust that are ultimately incorporated into stars and planets. Sulfur is an abundant but peculiar…

Astrophysics of Galaxies · Physics 2021-03-17 Javier R. Goicoechea , Sara Cuadrado

One of the main problems in astrochemistry is determining the amount of sulfur in volatiles and refractories in the interstellar medium. The detection of the main sulfur reservoirs (icy H$_2$S and atomic gas) has been challenging, and…

This paper is the fourth in a series whose purpose is to study the interstellar abundances of sulfur, chlorine, and argon in the Galaxy using a sample of 86 planetary nebulae. Here we present new high-quality spectrophotometric observations…

Astrophysics · Physics 2009-11-07 K. B. Kwitter , R. B. C. Henry , J. B. Milingo

This paper is the first of a series specifically studying the abundances of sulfur, chlorine, and argon in Type II planetary nebulae (PNe) in the Galactic disk. Ratios of S/O, Cl/O, and Ar/O constitute important tests of differential…

Astrophysics · Physics 2009-11-06 K. B. Kwitter , R. B. C. Henry

We have undertaken a large spectroscopic survey of over 80 planetary nebulae with the goal of providing a homogeneous spectroscopic database between 3600-9600 Angstroms, as well as a set of consistently determined abundances, especially for…

Astrophysics · Physics 2009-11-07 J. B. Milingo , R. B. C. Henry , K. B. Kwitter

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…

Astrophysics · Physics 2009-11-10 P. E. Nissen , Y. Q. Chen , M. Asplund , M. Pettini

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.…

Astrophysics · Physics 2009-11-11 E. Caffau , P. Bonifacio , R. Faraggiana , P. Francois , R. G. Gratton , M. Barbieri

Sulfur abundances derived from optical emission line measurements and ionization correction factors in planetary nebulae are systematically lower than expected for the objects' metallicities. We have carefully considered a large range of…

Astrophysics of Galaxies · Physics 2015-06-04 R. B. C. Henry , A. Speck , A. I. Karakas , G. J. Ferland , M. Maguire

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…

Astrophysics · Physics 2009-11-13 P. E. Nissen , C. Akerman , M. Asplund , D. Fabbian , F. Kerber , H. U. Kaufl , M. Pettini

Recent accurate abundance analyses of B-type main sequence stars in the solar vicinity has shown that abundances derived from these stellar objects are more homogeneous and metal-rich than previously thought. We investigate whether the…

Solar and Stellar Astrophysics · Physics 2015-05-14 S. Simón-Díaz

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…

Astrophysics of Galaxies · Physics 2013-12-18 E. Matrozis , N. Ryde , A. K. Dupree

(Abridged) The abundances of alpha-elements are a powerful diagnostic of the star formation history and chemical evolution of a galaxy. Sulphur, being moderately volatile, can be reliably measured in the interstellar medium (ISM) of damped…

Solar and Stellar Astrophysics · Physics 2015-06-22 E. Caffau , L. Monaco , M. Spite , P. Bonifacio , G. Carraro , H. -G. Ludwig , S. Villanova , Y. Beletsky , L. Sbordone

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…

Astrophysics of Galaxies · Physics 2021-03-31 J. Perdigon , P. de Laverny , A. Recio-Blanco , E. Fernandez-Alvar , P. Santos-Peral , G. Kordopatis , M. A. Alvarez

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…

Solar and Stellar Astrophysics · Physics 2020-02-26 Ana Rita Costa Silva , Elisa Delgado Mena , Maria Tsantaki
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