Magnetic star-disk interaction in young stars

Jérôme Bouvier
Outline  Accretion disks : from boundary layers to magnetospheric accretion  Magnetic field measurements in young stars  Magnetically-controlled star-disk interaction : obs. and models  The time variability of accretion/ejection : inner disks warps, funnel flows, accretion shocks  Impact on angular momentum evolution, disc lifetimes and planet formation A short historical note : from boundary layer accretion to magnetospheric accretion Accretion disks Viscous energy dissipation rate in the
more » ... disk : → IR excess Boundary layer (energy dissipation in a narrow equatorial belt) : → UV excess Accretion luminosity : Stellar Photosphere Bertout, Basri, Bouvier 1988 Accretion disks in young stars account in a simple and elegant way for their exotic properties, most notably their UV and IR continuum excesses. ≤ L star M acc~1 0 -8 M o /yr Boundary layer accretion ? Periodic modulation of the UV and optical excesses indicative of "hot spots" at the stellar surface. DF Tau (P=8.5d)