Reference : ELEMENT DIFFUSION IN THE SOLAR INTERIOR
Scientific journals : Article
Physical, chemical, mathematical & earth Sciences : Earth sciences & physical geography
http://hdl.handle.net/2268/78964
ELEMENT DIFFUSION IN THE SOLAR INTERIOR
English
Thoul, Anne mailto [Université de Liège - ULg > Département d'astrophys., géophysique et océanographie (AGO) > Astrophysique stellaire théorique et astérosismologie >]
BAHCALL, J. N. [> > > >]
LOEB, A. [> > > >]
1994
Astrophysical Journal
University of Chicago Press
421
2
828-842
Yes (verified by ORBi)
International
0004-637X
1538-4357
Chicago
IL
[en] DIFFUSION ; STARS, ABUNDANCES ; STARS, INTERIORS ; SUN, INTERIOR
[en] We study the diffusion of helium and other heavy elements in the solar interior by solving exactly the set of flow equations developed by Burgers for a multicomponent fluid, including the residual heat-flow terms. No approximation is made concerning the relative concentrations, and no restriction is placed on the number of elements considered. We give improved diffusion velocities for hydrogen, helium, oxygen, and iron, in the analytic form derived previously by Bahcall & Loeb. These expressions for the diffusion velocities are simple to program in stellar evolution codes and are expected to be accurate to similar to 15%. We find that the inclusion of the residual heat flow terms leads to an increase in the hydrogen diffusion velocity. We compare our numerical results-with those obtained analytically by Bahcall & Loeb using a simplified treatment, as well as with those derived numerically by Michaud & Proffitt. We find that for conditions characteristic of the Sun, the results of Bahcall & Loeb for the hydrogen diffusion velocity are smaller than our more accurate numerical results by similar to 30%, except very near the center where the error becomes larger. The Michaud & Proffitt results differ from the numerical results derived here by less than or similar to 15%. Our complete treatment of element diffusion can be directly incorporated in a standard stellar evolution code by means of an exportable subroutine, but, for convenience, we also give simple analytical fits to our numerical results.
http://hdl.handle.net/2268/78964
http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?1994ApJ...421..828T&data_type=PDF_HIGH&whole_paper=YES&type=PRINTER&filetype=.pdf

File(s) associated to this reference

Fulltext file(s):

FileCommentaryVersionSizeAccess
Open access
ApJ1994.pdfAuthor preprint189.09 kBView/Open

Bookmark and Share SFX Query

All documents in ORBi are protected by a user license.