Stochastic excitation and memory of the solar dynamo.

Details Stochastic excitation and memory of the solar dynamo. Stochastic excitation and memory of the solar dynamo.

Sep 1996

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1996a%26a...313..938o&link_type=abstract

Astronomy and Astrophysics, v.313, p.938-948

Astronomy and Astrophysics

Astrophysics

52

Sun: Magnetic Fields, Sunspots, Convection, Turbulence

Scientific paper

We consider a simple axisymmetric mean field dynamo model for the Sun in the α{OMEGA}-limit and study the effect of rapid, latitude dependent stochastic fluctuations in α. The fluctuations excite overtones of the fundamental mode of the mean magnetic field. We decompose the mean field into eigenmodes and derive an equation for the mode coefficients. Transient mode excitation gives rise to a mean field with spatial and temporal variability, and may provide an explanation for grand minima, the observed phase-amplitude correlation, North-South asymmetries and, close to the equator, reverse polarity regions in the solar butterfly diagram. We find that the North-South asymmetry often peaks near the activity minimum, in agreement with the observations. The most likely candidate for the origin of the fluctuations are giant cells. Sunspot data are well reproduced if α, defined as an azimuthal average, has fluctuations δα of the order δα/α_0_=~3 at colatitude θ=60deg, assuming that there are 20 giant cells from pole to pole, with a coherence time of 1 month. The model predicts that the resulting phase and amplitude fluctuations of the fundamental mode are correlated for about 90 dynamo periods.

Affiliated with

Also associated with

No associations

Rating

Stochastic excitation and memory of the solar dynamo. 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 Stochastic excitation and memory of the solar dynamo., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Stochastic excitation and memory of the solar dynamo. will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1455948