S. Talon et C. Charbonnel, THE LI DIP - A PROBE OF ANGULAR-MOMENTUM TRANSPORT IN LOW-MASS STARS, Astronomy and astrophysics (Berlin), 335(3), 1998, pp. 959-968
We use the measures of Li and rotational velocities in F Hyades stars
to assess the role of the wind-driven meridian circulation and of shea
r turbulence in the transport of angular momentum in stars of differen
t masses. Our models include both element segregation and rotation-ind
uced mixing, and we treat simultaneously the transport of matter and a
ngular momentum as described by Zahn (1992) and Maeder (1995). We show
that the hot side of the Li dip in the Hyades is well explained withi
n this framework, which was also successfully used to reproduce the C
and N anomalies in B type stars (Talon et al. 1997). On the cool side
of the dip, another mechanism must participate in the transport of ang
ular momentum; its efficiency is linked to the depth of the surface co
nvection zone. That mechanism should also be responsible for the Sun's
flat rotation profile.