Abstract
A brief summary of the various observations and constraints that underlie
solar dynamo research are presented. The arguments that indicate that the solar
dynamo is an alpha-omega dynamo of the Babcock-Leighton type are then shortly
reviewed. The main open questions that remain are concerned with the subsurface
dynamics, including why sunspots emerge at preferred latitudes as seen in the
familiar butterfly wings, why the cycle is about 11 years long, and why the
sunspot groups emerge tilted with respect to the equator (Joy's law). Next, we
turn to magnetic helicity, whose conservation property has been identified with
the decline of large-scale magnetic fields found in direct numerical
simulations at large magnetic Reynolds numbers. However, magnetic helicity
fluxes through the solar surface can alleviate this problem and connect theory
with observations, as will be discussed.
Users
Please
log in to take part in the discussion (add own reviews or comments).