HALL CURRENT EFFECTS IN MEAN-FIELD DYNAMO THEORY
نویسندگان
چکیده
منابع مشابه
On the mean field dynamo with Hall effect
Context. MHD turbulence with Hall effect. Aims. Study how Hall effect modifies the quenching process of the electromotive force (e.m.f.) in Mean Field Dynamo (MFD) theories. Methods. We write down the evolution equations for the e.m.f. and for the large and small scale magnetic helicity, treat Hall effect as a perturbation and integrate the resulting equations, assuming boundary conditions such...
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 کاملMean-field helicity in random α-dynamo twisted flows
Recent results by Shukurov, Stepanov and Sokoloff [Phys. Rev. E 78,025301,(2008)] on dynamo action in Moebius strip flows, indicate that strong magnetic fields appear in regions where, electric current and flow kinetic helicities have the same sign. Here, an analytical version of their numerical result is obtained by a simpler method of considering the laminar non-turbulent limit, of a twisted ...
متن کاملZonal 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 کاملDynamo Theory and Earth’s Magnetic Field
The Earth’s magnetic field belongs in that class of physical phenomena which are commonplace yet also very complex. It is commonplace in that almost everyone knows that it exists, yet not very many people (probably including a good percentage of physicists) know how it works. The theory behind the generation of a magnetic field, known as dynamo theory, is still an active area of research. The e...
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: The Astrophysical Journal
سال: 2016
ISSN: 1538-4357
DOI: 10.3847/0004-637x/829/1/51