2008/12/19 by K. Pavlovski, J. Southworth
Physics and Astronomy · #Abundance of the chemical elements #Astronomy #Astronomy and Astrophysical Research #Astrophysics #Astrophysics and Star Formation Studies #Balmer series #Binary star #Effective temperature #Emission spectrum #K-type main-sequence star #Main sequence #Microturbulence #Photosphere #Physics #Spectral line #Stars #Stellar evolution #Stellar, planetary, and galactic studies #T Tauri star #astro-ph
paper · pdf · doi:10.1111/j.1365-2966.2009.14418.x
10 pages; accepted for publication in MNRAS
arxiv created 2008/12/19 · openalex publication_date 2009/03/10 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The eclipsing and double-lined spectroscopic binary system V453 Cygni consists of two early B-type stars, one of which is nearing the terminal age main sequence and one which is roughly halfway through its main-sequence lifetime. Accurate measurements of the masses and radii of the two stars are available, which makes a detailed abundance analysis both more interesting and more precise than for isolated stars. We have reconstructed the spectra of the individual components of V453 Cyg from the observed composite spectra using the technique of spectral disentangling. From these disentangled spectra, we have obtained improved effective temperature measurements of 27 900 ± 400 and 26 200 ± 500 K, for the primary and secondary stars, respectively, by fitting non local thermodynamic equilibrium theoretical line profiles to the hydrogen Balmer lines. Armed with these high-precision effective temperatures and the accurately known surface gravities of the stars we have obtained the abundances of helium and metallic elements. A detailed abundance analysis of the primary star shows a normal (solar) helium abundance if the microturbulence velocity derived from metallic lines is used. The elemental abundances show no indication that CNO-processed material is present in the photosphere of this high-mass terminal age main-sequence star. The elemental abundances of the secondary star were derived by a differential study against a template spectrum of a star with similar characteristics. Both the primary and secondary components display elemental abundances which are in the ranges observed in the Galactic OB stars.