Dynamo-parameters of the convection zone of the Sun
| 1Kryvodubskyj, VN 1Astronomical Observatory, Taras Shevchenko National University of Kyiv, 04053, Kyiv, Ukraine |
| Kinemat. fiz. nebesnyh tel (Online) 2006, 22(1):3-28 |
| Start Page: Solar Physics |
| Язык: Ukrainian |
Аннотация: In the framework of the macroscopic magnetohydrodynamics in the mixing length approach, we investigated the basic dynamo-parameters (helicity of turbulent convection and radial gradient of angular velocity) of the solar convection zone (SCZ) with taking into account the radial inhomogeneity of turbulent pulsations, magnetic quenching of helical convection and newest helioseismological progress in tracing of inner rotation of the Sun. Allowance for the harp radial gradient in turbulent velocity results in a change of sign of the helicity parameter from positive to negative (in the northern hemisphere) and, as a consequence, in the formation of the negative α-effect layer near the bottom of the SCZ. This deep negative α-effect layer is responsible for observed meridional migration of the surface large-scale magnetic patterns. When one takes into account the magnetic alpha-quenching and the radial gradient of angular velocity ∂ꭥ/ ∂r, obtained in the recent helioseismological measurements, then the calculated dynamo-wave period is about seven years, which agrees by order of magnitude with the observed sunspot cycles mean duration. It is demonstrated that the αꭥ-dynamo can reproduce the mixed north-south magnetic parity, observed at the activity maxima epochs, if we take into account the negative α-effect near the bottom of the SCZ and use the parameter ∂ꭥ/∂r derived from helioseismological inversions and having opposite signs in the equatorial and polar domains. |
| Ключевые слова: convection zone, Sun |
