Stellar evolution models with mass loss and turbulence
Although chemical separation is generally accepted as the main physical process responsible for the anomalous surface abundances of AmFm stars,its exact behavior within the interior of these stars is still uncertain. We will explore two hydrodynamical processes which could compete with atomic diffusion: mass loss and turbulence. We will also discuss the extent to which separation occurs immediately below the surface convection zone as well as the extent to which separation occurs below 200,000 K. To do so,self-consistent stellar models with mass loss and turbulence where calculated using the Montreal stellar evolution code and compared to observations of A and F stars. It is shown that to the precision of observations available for F stars,a mass loss rate of 2×10-14 M☉ · yr-1 is compatible with observations and that no turbulence is then required.
stars:evolution stars:abundances stars:mass loss turbulence
M.Vick G.Michaud O.Richard
Departement de Physique,Université de Montréal,Montréal,PQ,H3C 3J7;GRAAL,Universite Montpellier Ⅱ,CN Departement de Physique,Université de Montreal,Montreal,PQ,H3C 3J7 GRAAL,Universite Montpellier Ⅱ,CNRS,Place E.Bataillon,34095 Montpellier Cedex,France
国际会议
The 252th Symposium of the International Astronomical Union(国际天文学联合会第252届研讨会)
海南三亚
英文
289-296
2008-04-06（万方平台首次上网日期，不代表论文的发表时间）