Speaker
Axel Brandenburg
(Nordita)
Description
One of the original reasons for placing the solar dynamo at the bottom of the
convection zone was the possibility of rapid loss of magnetic fields by magnetic
buoyancy. In various simulations, however, turbulent pumping is often seen to be
dominant. Other reasons for placing the dynamo at the bottom of the convection zone
was that alpha would have a different (favorable) sign there, and that the size of
active regions is more naturally explained by the natural length scales occurring in
deeper layers. Meanwhile, however, mean-field phenomena such as the negative
effective magnetic pressure instability have emerged as new possibilities explaining
the formation of flux concentrations on scales much larger than the local turbulent
eddy size. In my talk, I will elaborate on the current status of such a proposal.
Primary author
Axel Brandenburg
(Nordita)
