2001/09/06 by S. Goriely, Stephane Goriely, L. Siess +1 · 2 citations
Physics and Astronomy · #Astronomy and Astrophysical Research #Envelope (radar) #Mixing (physics) #Neutron star #Nucleosynthesis #Population #Pulsars and Gravitational Waves Research #Stars #Stellar evolution #Stellar nucleosynthesis #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1051/0004-6361:20011249
4 pages, 3 Postscript figures, uses aa.sty. Accepted for publication in A&A Letters
arxiv created 2001/09/06 · openalex publication_date 2001/10/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Contrary to previous expectations, recent evolutionary models of zero-metallicity stars show that the development of mixing episodes at the beginning of the AGB phase allows low- and intermediate-mass stars to experience thermal pulses. If these stars, like their metal-rich counterparts, also experience partial mixing of protons from the H-rich envelope into the C-rich layers at the time of the third dredge-up, an extensive neutron capture nucleosynthesis leads to the production of s-process nuclei up to Pb and Bi. Nucleosynthesis calculations based on stellar AGB models are performed assuming a parameterized H-abundance profile below the convective envelope at the time of the third dredge-up. Despite the absence of Fe-group elements, the large neutron flux resulting from the 13C(α,n)16O reaction leads to an efficient production of s-process elements starting from the neutron captures on the C-Ne isotopes. Provided partial mixing of protons takes place, it is shown that population III AGB stars should be enriched in s-process elements and overall in Pb and Bi.