Специализация: 010700/07 Физика Земли и планет
Программа: 03 Физика солнечно-земных связей
Руководитель программы: проф. В.С. Семенов
Кафедра физики Земли
Научный руководитель: проф. В.С. Семенов
Рецензент:. д. ф.-м. н. Е.Е. Беневоленская 

Oscillations of a thin magnetic flux tube inside polytropic star
Bortnikov R.O.

Dissertation is devoted to the dynamics of toroidal magnetic fields inside polytopic star which is necessary to learn how the solar cycle works. The toroidal field is modeled by single thin flux tube (nonlinear string). Flux tube inside the star is driven by several forces, namely: background pressure gradient, gravitation force, inertial force and maxwellian stress. 
Model of background pressure in polytrope with homogenous rotation has been developed. Lagrangian density of the flux tube has been analyzed, from which motion equations and effective potential in the equatorial plane have been derived. Equations of motion take the form of nonlinear string equations. Analysis of potential energy density showed that there are two possible regimes of motion for axisymmetrical string: emerging to the surface and finite oscillations. Dependence of regime on initial magnetic field inside the tube and its initial position has been studied. Numerical simulations were carried out to confirm conducted analysis.
The list of the publications
1. Бортников Р.О., Семенов В.С. Изучение плавучести магнитных силовых трубок в горизонтальной солнечной атмосфере // Труды XI Конференции молодых ученых "Гелио- и геофизические исследования", БШФФ-2009. Изд-во ИСЗФ СО РАН, Иркутск, 2009, с. 232-235.