Stellar models with rotation: an exploratory application to pre-main sequence Lithium Depletion.

Claret, A.; Martin, E. L.
Referencia bibliográfica

Astronomy and Astrophysics, v.306, p.408

Fecha de publicación:
2
1996
Número de autores
2
Número de autores del IAC
1
Número de citas
90
Número de citas referidas
72
Descripción
Over the last 20 years, the surface abundance of Li has been derived for a significant number of low mass pre-main sequence (PMS) stars. Several works have pointed out the unexpected large Li spread for young stars of similar ages and masses. This spread still represents a challenge in our understanding of PMS stellar evolution. Almost in parallel, it has also become clear that there is a large dispersion in rotational velocities among PMS low mass stars. Recent observations indicate the existence of a Li-rotation relationship among weak-line T Tauri stars and confirm it among members of young open clusters (αPer, Pleiades). Such a link is most clear for PMS stars with masses around 0.8Msun_. In this paper we present an exploratory study on the influence of rotation on Li depletion in PMS evolution. We have computed the contraction of 0.8-0.7Msun_ rotating stellar models (up to an age of 10^8^years) with constant angular momentum. We find that the presence of rapid rotation in PMS evolution inhibits significantly the depletion of Li and allows to physically understand the observed Li abundance spread among late-type PMS stars. Also, we confim previous results that rotation changes the position of PMS tracks in the HR diagram. The differences in effective temperature between standard and rotating models can be as high as 5%.