Theory of solar magnetic flux tubes

Using the mathematics of the theory of orthogonal spherical vectors, we con sider isolated axisymmetric equilibrium magnetic flux tubes on the Sun. In this approach, a regular (over the entire space) magnetic field can be cons tructed. We analyze the difficulties that are caused by the disruption of t hermal balance due to the "coupling" of various spherical harmonics. These difficulties vanish in the case of a dipole magnetic field. We discuss a mo del for an isolated magnetic flux tube with such a small diameter that the perturbations of thermal balance produced by the tube are at the level of r andom chaotic fluctuations.