Physics
Scientific paper
Feb 2006
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2006soph..233..185k&link_type=abstract
Solar Physics, Volume 233, Issue 2, pp.185-204
Physics
7
Scientific paper
We present a straightforward comparison of model calculations for the α-effect, helicities, and magnetic field line twist in the solar convection zone with magnetic field observations at atmospheric levels. The model calculations are carried out in a mixing-length approximation for the turbulence with a profile of the solar internal rotation rate obtained from helioseismic inversions. The magnetic field data consist of photospheric vector magnetograms of 422 active regions for which spatially-averaged values of the force-free twist parameter and of the current helicity density are calculated, which are then used to determine latitudinal profiles of these quantities. The comparison of the model calculations with the observations suggests that the observed twist and helicity are generated in the bulk of the convection zone, rather than in a layer close to the bottom. This supports two-layer dynamo models where the large-scale toroidal field is generated by differential rotation in a thin layer at the bottom while the α-effect is operating in the bulk of the convection zone. Our previous observational finding was that the moduli of the twist factor and of the current helicity density increase rather steeply from zero at the equator towards higher latitudes and attain a certain saturation at about 12 15∘. In our dynamo model with algebraic nonlinearity, the increase continues, however, to higher latitudes and is more gradual. This could be due to the neglect of the coupling between small-scale and large-scale current and magnetic helicities and of the latitudinal drift of the activity belts in the model.
Kuzanyan Kirill M.
Pipin Valery V.
Seehafer Norbert
No associations
LandOfFree
The Alpha Effect and the Observed Twist and Current Helicity of Solar Magnetic Fields does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The Alpha Effect and the Observed Twist and Current Helicity of Solar Magnetic Fields, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Alpha Effect and the Observed Twist and Current Helicity of Solar Magnetic Fields will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1165354