17th Cambridge Workshop on Cool Stars, Stellar Systems and the Sun
June 24-29, 2012
Type: Invited
Topic: Evolved Stars and Hot-Cool Star Connection
Abstract
The talk reviews the key observational facts but will focus on the theoretical understanding of magnetic fields in radiative zones of intermediate-mass stars. The results for magnetic instabilities and dynamo effect are then seen in view of their effects in cool stars of which in fact many also have a radiative part. We now have a detailed understanding of these magnetic instabilities and can draw first conclusions about the dynamo effect expected from them. The activity of cool stars may actually be only understandable if the dynamo process is seen in conjunction with magnetic instabilities.