Articolo in rivista, 2011, ENG, 10.1063/1.3647330

Barriers in the transition to global chaos in collisionless magnetic reconnection. II. Field line spectroscopy

D. Borgogno (1); D. Grasso (2); F. Pegoraro (3); T. J. Schep (4)

1) Dipartimento di Energetica, Politecnico di Torino, Torino, Italy 2) CNR Consiglio Nazionale delle Ricerche, Istituto dei Sistemi Complessi, Dipartimento di Energetica, Politecnico di Torino, Torino, Italy 3) Department of Physics, Pisa University, Pisa CNISM, Italy 4) Department of Physics, Eindhoven University of Technology, Eindhoven, The Netherlands

The transitional phase from local to global chaos in the magnetic field of a reconnecting current layer is investigated. The identification of the ridges in the field of the finite time Lyapunov exponent as barriers to the field line motion is carried out adopting the technique of field line spectroscopy to analyze the radial position of a field line while it winds its way through partial stochastic layers and to compare the frequencies of the field line motion with the corresponding frequencies of the distinguished hyperbolic field lines that are the nonlinear generalizations of linear X-lines.

Physics of plasmas 18 (10), pp. 102308-1–102308-7

Keywords

chaos, Lyapunov methods, magnetic reconnection, plasma fluctuations

CNR authors

Grasso Daniela

CNR institutes

ISC – Istituto dei sistemi complessi