Petschek-like Reconnection with Current-driven Anomalous Resistivity and its Application to Solar Flares
arXiv:astro-ph/0212398 · doi:10.1086/368075
Abstract
Recent numerical simulations of magnetic reconnection in two dimensions have shown that, when the resistivity is strongly localized, the reconnection region develops a Petschek-like structure, with the width of the inner diffusion region being of the order of the resistivity localization scale. In this paper, we combine this fact with a realistic model for locally-enhanced anomalous resistivity generated by current-driven microturbulence. The result is a qualitative model of the reconnection layer where the size of Petschek's diffusion region and, therefore, the final reconnection rate are determined self-consistently in terms of the main parameters of the functional dependence of anomalous resistivity on the electric current density. We then consider anomalous resistivity due to ion-acoustic turbulence as a particular case. This enables us to express the reconnection region's parameters directly in terms of the basic parameters of the plasma. Finally, we apply this reconnection model to solar flares and obtain specific predictions for typical reconnection times, which are very consistent with observations.
30 pages, 3 figures. Short version has been accepted by the Astrophysical Journal (vol.587 n1 -- April 10, 2003 issue)
References in corpus (3)
Cited by in corpus (16)
- On Solving the Coronal Heating Problem
- Multi-fluid simulations of chromospheric magnetic reconnection in a weakly ionized reacting plasma
- Particle acceleration and transport in reconnecting twisted loops in a stratified atmosphere
- Fast Collisionless Reconnection Condition and Self-Organization of Solar Coronal Heating
- Relativistic resistive magnetohydrodynamic reconnection and plasmoid formation in merging flux tubes
- From Solar and Stellar Flares to Coronal Heating: Theory and Observations of How Magnetic Reconnection Regulates Coronal Conditions
- Self-Regulation of Solar Coronal Heating Process via Collisionless Reconnection Condition
- Ion and Electron Acoustic Bursts during Anti-Parallel Magnetic Reconnection Driven by Lasers
- Fast Shocks From Magnetic Reconnection Outflows
- Magnetic explosions: role of the inductive electric field
- An evaluation of possible mechanisms for anomalous resistivity in the solar corona
- Two-fluid reconnection jets in a gravitationally stratified atmosphere
- A Two-dimensional Numerical Study of Ion-Acoustic Turbulence
- Fast Magnetic Reconnection induced by Resistivity Gradients in 2D Magnetohydrodynamics
- Global Energetics of Solar Flares: X. Petschek Reconnection Rate and Alfven Mach Number of Magnetic Reconnection Outflows
- Role of ion acoustic instability in magnetic reconnection