Energy Release in the Current-Carrying Magnetic Loops

  • V. V. Zaitsev

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:

$$\frac{{\partial {B_z}}}{{\partial r}} = \frac{{4\pi \sigma {V_r}}}{{{c^2}}}\frac{{{B_z}}}{{1 + \alpha B_z^2 + \alpha B_\varphi ^2}},\frac{1}{r}\frac{{\partial \left( {rB\varphi } \right)}}{{\partial r}} = \frac{{4\pi \sigma {V_r}}}{{{c^2}}}\frac{{{B_\varphi }}}{{1 + \alpha B_z^2 + \alpha B_\varphi ^2}}$$
(1)

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 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

References

  1. Henoux, J.C. and Somov, B.V. (1991) The photospheric dynamo, Astronomy and Astrophys. 241, 613.ADSGoogle Scholar
  2. Melrose, D.B. and Khan, J.I. (1989) Comments on the photospheric dynamo model of Henoux and Somov, Astronomy and Astrophys. 219, 308.ADSGoogle Scholar
  3. Sen, H.K. and White, M.L. (1972) A physical mechanism for the production of solar flare, Solar Phys. 23, 146.ADSCrossRefGoogle Scholar
  4. Wheatland, M.S. and Melrose, D.B. (1995) Energy release in a prominence loaded flaring loop, Solar Phys. accepted.Google Scholar
  5. Zaitsev, V.V. and Stepanov, A.V. (1992) Towards the circuit theory of solar flares, Solar Phys. 139, 343.ADSCrossRefGoogle Scholar

Copyright information

© Kluwer Academic Publishers 1996

Authors and Affiliations

  • V. V. Zaitsev
    • 1
  1. 1.Institute of Applied PhysicsRussian Academy of ScienceNizhnii NovgorodRussia

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