Volume 395, Number 1, November III 2002
|Page(s)||85 - 95|
|Section||Interstellar and circumstellar matter|
|Published online||29 October 2002|
Microscopic diffusion of partly ionized metals in the Sun and metal-poor stars
Astrophysics Research Institute, Liverpool John Moores University, Twelve Quays House, Egerton Wharf, Birkenhead CH41 1LD, UK
Corresponding author: firstname.lastname@example.org
Accepted: 21 August 2002
An improved microscopic diffusion in stars is presented considering in detail the partly ionized stages of metals. Besides, the influence of degenerate electron-gas and of the contribution of radiation to the total pressure has been accounted for. The solution of the diffusion equations is then performed following the scheme of Thoul et al. ([CITE]). By defining one mean charged ion per element very few modifications are necessary to solve the improved diffusion scheme. (A portable FORTRAN routine is provided.) The change in the sound-speed profile of a solar model obtained with the new diffusion description is at most about 25% at . The biggest effect on low-mass stars is expected near the turn off, where the convective envelope is shallowest. However, only a difference of at most 40 K in the effective temperature could be observed when assuming either fully or partly ionized metals in the diffusion equation. Nevertheless, the surface metal distribution is strongly altered.
Key words: Sun: interior / stars: evolution / stars: abundances / Hertzsprung-Russel (HR) diagram
© ESO, 2002
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.