Magnetodynamic Phenomena in the Solar Atmosphere pp 317-318 | Cite as

# Energy Release in the Current-Carrying Magnetic Loops

## Abstract

In the present talk we consider 1) generation of currents inside a magnetic loop due to photospheric convection; 2) some features of a steady-state Joule dissipation of these currents; 3) possibility of explosive Joule dissipation caused by current disruption in a magnetic loop due to a flute instability. Generation of an electric current in a magnetic loop by a photospheric plasma motion is described by a generalized Ohm’s law, and by an equation for a plasma motion.If velocity of convective motion in the photosphere **V** = {*V* _{ r }, 0, 0}, where *V* _{ r } = *V* _{0} *r* _{0}/*r* _{0} (*r* < *r* _{0}), *V* _{ r } = *V* _{0} *r* _{0}/*r* (*r* > *r* _{0}) is directed towards the axis of a vertical magnetic loop, we obtain the following set of equations for the components *B* _{ z }, *B* _{ ϕ } of magnetic field in the loop:

where \(\sigma = \frac{{{e^2}n}}{{{m_e}\left( {{v_{ei}} + {v_{ea}}} \right)}},\alpha = \frac{{\alpha F}}{{{c^2}n{m_i}{v_{ia}}}},{v_{ei}},{v_{ea}},{v_{ia}}\) are respectively effectivefrequencies of collisions of electrons with ions and neutrals, and ions with neutrals, *p* _{ k } is gas kinetic pressure, *ρ*, plasma density, *F* = *ρ* _{ a }/*ρ*, relative density of neutrals, *n*, number density of electrons.

## Keywords

Solar Phys Solar Flare Magnetic Loop Magnetic Tube Plasma Motion## References

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