منابع مشابه
Zonal flows in a mean-field solar dynamo model
Cyclic variations are observed in the solar differential rotation profile. The 11 year periodicity of these zonal shear flows (often referred to as “torsional oscillations”) is consistent with the idea that they are driven by the Lorentz forces that are associated with the large-scale solar dynamo. This suggests that these flows may be able to provide indirect observational evidence that can be...
متن کاملGrand Minima of Solar Activity and the Mean-Field Dynamo
We demonstrate that a simple solar dynamo model, in the form of a Parker migratory dynamo with random fluctuations of the dynamo governing parameters and algebraic saturation of dynamo action, can at least qualitatively reproduce all the basic features of solar Grand Minima as they are known from direct and indirect data. In particular, the model successfully reproduces such features as an abru...
متن کاملA numerical dynamo benchmark
We present the results of a benchmark study for a convection-driven magnetohydrodynamic dynamo problem in a rotating spherical shell. The solutions are stationary aside from azimuthal drift. One case of non-magnetic convection and two dynamos that differ in the assumptions concerning the inner core are studied. Six groups contributed numerical solutions which show good agreement. This provides ...
متن کاملSmall-scale magnetic helicity losses from a mean-field dynamo
Using mean-field models with a dynamical quenching formalism, we show that in finite domains magnetic helicity fluxes associated with small-scale magnetic fields are able to alleviate catastrophic quenching. We consider fluxes that result from advection by a mean flow, the turbulent mixing down the gradient of mean small-scale magnetic helicity density or the explicit removal which may be assoc...
متن کاملMixed-parity Solutions in a Mean-field Dynamo Model
S u m m a r y : We consider the effect of including both dipole and quadrupole parities in the previous mean-field model of Hollerbach and Jones (1995), which considered dipole parity only. Allowing for both parities, we find that the onset of dynamo action occurs at a0 « 6, in the form of a purely quadrupolar dynamo wave. A symmetry-breaking bifurcation then occurs at ao « 11, beyond which the...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Astronomy & Astrophysics
سال: 2008
ISSN: 0004-6361,1432-0746
DOI: 10.1051/0004-6361:20078351