Analytical model of fast magnetic reconnection with a large guide field
- Los Alamos National Laboratory (LANL)
- ORNL
- Politecnico di Torino
Nonlinear analytical theory of magnetic reconnection with a large guide field is presented for the first time. We confirm that two distinct steady-state reconnection regimes are possible depending on the relative size of the diffusion region thickness {delta} versus the sound gyroradius {rho}{sub s}. The reconnection is slow (Sweet-Parker-like) for {delta} {ge} {rho}{sub s}, and fast otherwise. However, unlike earlier work, we find that ion viscosity {mu} plays a fundamental role in the fast regime. In particular, for {delta} < {rho}{sub s} we obtain {delta} {infinity} Ha{sup -1}, with Ha {infinity} 1/{radical}{nu}{mu} as the Hartmann number, and the reconnection rate E{sub z} {infinity} Pr{sup -1/2}, with Pr = {mu}/{eta} as the Prandtl number and {eta} as the resistivity. If the perpendicular ion viscosity is employed for {mu}, the reconnection rate becomes independent of plasma {beta} and collision frequencies, and therefore potentially fast.
- Research Organization:
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC)
- DOE Contract Number:
- DE-AC05-00OR22725
- OSTI ID:
- 983569
- Journal Information:
- Physics of Plasmas, Vol. 17, Issue 6; ISSN 1070-664X
- Country of Publication:
- United States
- Language:
- English
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