On hydrodynamic mechanism of phase change of the Sun's dynamo-cycle

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Space and Atmospheric Physics
1Loginov, AA, 1Tkachenko, VA, 1Cheremnykh, OK
1Space Research Institute of the National Academy of Sciences of Ukraine and the State Space Agency of Ukraine, Kyiv, Ukraine
Kosm. nauka tehnol. 2007, 13 ;(Supplement1):093-098
https://doi.org/10.15407/knit2007.01s.093
Publication Language: Russian
Abstract: 
The model of phase change for the Sun's magnetic field generation is proposed. The mechanism of the change is as follows. Due to stability loss of toroidal differential rotation of the Sun at the threshold value of the relationship between the angular velocity and radius and latitude Ω (r, θ) poloidal flows arise and the dynamo-process associated with them and generating the Sun's variable magnetic field occurs. Influence of the Coriolis force on the poloidal flows brakes the differential rotation, which causes a change in structure of Ω (r, θ) and violation of the instability condition. This results in the disappearance of the poloidal flows and in the interruption of the dynamo-process. Then the differential rotation and dynamo-cycle are regained and when the angular velocity reaches the threshold value the Sun's variable magnetic field is generated again.
Keywords: angular velocity, differential rotation, dynamo-cycle
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