Presentation 1 : Invited
Magnetic fields and large-scale flows of matter: the case of young stars
T. Montmerle
Because they are surrounded by dense circumstellar material, either via
accretion (from disks) or via ejection (winds, jets), and because they
are in general strongly magnetized, young stars (~ 10^6 yrs) offer a
unique laboratory to study large-scale mass transfer in cases where the
plasma is dominated by magnetic fields. This situation is reminiscent
of the case of the solar wind and the heliosphere. It will be
illustrated by two examples: (i) "magnetospheric accretion" in T Tauri
stars, and (ii) "magnetically confined radiative winds" in Ap-Bp stars.