Work

Forced 3D Reconnection in an Exponentially Separating Magnetic Field

Year: 2025

Type: article

Abstract: We present a solvable scenario for 3D reconnection in a sheared magnetic field. We consider a localized external force that is applied slowly to a flux tube and then maintained, generating an Alfvénic perturbation that spreads along the field lines. Separation of the sheared field lines reduces the scale of the perturbation across the field, enhancing magnetic diffusion. For a fusion-motivated equilibrium with exponential field-line separation, we find a reconnection timescale proportional to S/lnS under magnetohydrodynamics (MHD) and to S^{1/3} for semicollisional electron-only reconnection, where S is the Lundquist number of the perturbed flux tube. We generalize these results to arbitrary magnetic geometries, showing that the semicollisional case is geometry independent. Interestingly, we find that slower field-line separation yields an increased reconnection rate in MHD.

Source: Physical Review Letters

DOI: 10.1103/rd5d-93l7

Authors: David N. Hosking, Ian G. Abel, Steven C. Cowley

Institutions: Princeton University, University of Cambridge, University of Maryland, College Park, Princeton Plasma Physics Laboratory

Language: English

Topic: Magnetic confinement fusion research

Subfield: Nuclear and High Energy Physics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $3,750

OpenAlex ID: W4405035014

FWCI:

Cites: 25

Cited by:

Related to: 10