2007/03/27 by H. B. Lau, Herbert H. B. Lau, R. J. Stancliffe +3 · 1 citation
Physics and Astronomy · #Astro and Planetary Science #Astrophysics and Star Formation Studies #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1111/j.1365-2966.2007.11773.x
published as Mon.Not.Roy.Astron.Soc.378:563-568,2007 · 16 pages, 1 figure, 7 tables, accepted by MNRAS
arxiv created 2007/03/27 · openalex publication_date 2007/05/26 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We use the Cambridge stellar evolution code stars to model the evolution and nucleosynthesis of zero-metallicity intermediate-mass stars. We investigate the effect of duplicity on the nucleosynthesis output of these systems and the potential abundances of the secondaries. The surfaces of zero-metallicity stars are enriched in CNO elements after second dredge-up. During binary interaction, such as Roche lobe overflow or wind accretion, metals can be released from these stars and the secondaries enriched in CNO isotopes. We investigate the formation of the two most metal poor stars known, HE 0107–5240 and HE 1327–2326. The observed carbon and nitrogen abundances of HE 0107–5240 can be reproduced by accretion of material from the companion-enhanced wind of a 7-M⊙ star after second dredge-up, though oxygen and sodium are underproduced. We speculate that HE 1327–2326, which is richer in nitrogen and strontium, may similarly be formed by wind accretion in a later asymptotic giant branch phase after third dredge-up.