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Reconnection rate for the inhomogeneous resistivity petschek model
1Institute of Computational Modelling, Russian Academy of Sciences, Krasnoyarsk 660036, Russia.
Physical Review Letters
|October 4, 2000
Summary
This study determines the reconnection rate in plasma by matching outer and inner solutions. The findings integrate both Sweet-Parker and Petschek models, with Petschek requiring localized resistivity.
Area of Science:
- Plasma physics
- Astrophysics
- Magnetohydrodynamics
Background:
- Magnetic reconnection is a fundamental process in plasma physics, crucial for phenomena like solar flares and geomagnetic storms.
- Previous models, such as the Sweet-Parker and Petschek models, offer different predictions for reconnection rates.
- A unified understanding of these models under various conditions is essential.
Purpose of the Study:
- To determine the reconnection rate for steady-state, two-dimensional, symmetric, and incompressible plasma reconnection.
- To develop a model that naturally incorporates both Sweet-Parker and Petschek reconnection regimes.
- To identify the conditions under which the Petschek regime becomes dominant.
Main Methods:
- Matching an outer Petschek solution with an internal diffusion region solution.
- Analyzing the behavior of reconnection rates in a simplified, canonical case.
- Investigating the role of resistivity localization in determining the reconnection regime.
Main Results:
- A reconnection rate is derived that unifies the Sweet-Parker and Petschek models.
- The derived rate is applicable to steady-state, 2D, symmetric, incompressible reconnection.
- The Petschek regime is shown to be possible only when resistivity is strongly localized.
Conclusions:
- The study provides a comprehensive model for magnetic reconnection rates.
- The findings highlight the critical role of resistivity distribution in plasma dynamics.
- This work advances the understanding of energy dissipation and particle acceleration in astrophysical plasmas.
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