Sulfur Abundances in the Orion Association B Stars

Abstract

Sulfur abundances are derived for a sample of ten B main-sequence star members of the Orion association. The analysis is based on LTE plane-parallel model atmospheres and non-LTE line formation theory by means of a self-consistent spectrum synthesis analysis of lines from two ionization states of sulfur, SII and SIII. The observations are high-resolution spectra obtained with the ARCES spectrograph at the Apache Point Observatory. The abundance distribution obtained for the Orion targets is homogeneous within the expected errors in the analysis: A(S)=7.15+/-0.05. This average abundance result is in agreement with the recommended solar value (both from modelling of the photospheres in 1-D and 3-D, and meteorites) and indicates that little, if any, chemical evolution of sulfur has taken place in the last ~4.5 billion years. The sulfur abundances of the young stars in Orion are found to agree well with results for the Orion nebulae, and place strong constraints on the amount of sulfur depletion onto grains as being very modest or nonexistent. The sulfur abundances for Orion are consistent with other measurements at a similar galactocentric radius: combined with previous results for other OB-type stars produce a relatively shallow sulfur abundance gradient with a slope of -0.037+/-0.012 dex/kpc.

Accepted for publication in The Astronomical Journal

References in corpus (11)

• A cosmic abundance standard: chemical homogeneity of the solar neighbourhood and the ISM dust-phase composition
• Sulphur and zinc abundances in Galactic halo stars revisited
• Low sulfur depletion in the Horsehead PDR
• Abundance gradients in the Milky Way for alpha elements, Iron peak elements, Barium, Lanthanum and Europium
• Abundance analysis of prime B-type targets for asteroseismology I. Nitrogen excess in slowly-rotating beta Cephei stars
• Nitrogen enrichment, boron depletion and magnetic fields in slowly-rotating B-type dwarfs
• Hydrogen and helium line formation in OB dwarfs and giants. A hybrid non-LTE approach
• Neon Abundances in B-Stars of the Orion Association: Solving the Solar Model Problem?
• The forbidden 1082 nm line of sulphur: the photospheric abundance of sulphur in the Sun and 3D effects
• Argon Abundances in the Solar Neighborhood: Non-LTE Analysis of Orion Association B-type Stars
• The Projected Rotational Velocity Distribution of a Sample of OB stars from a Calibration based on Synthetic He I lines

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