Relaxation Processes in Solar Wind Turbulence

Abstract

Based on global conservation principles, magnetohydrodynamic (MHD) relaxation theory predicts the existence of several equilibria, such as the Taylor state or global dynamic alignment. These states are generally viewed as very long-time and large-scale equilibria, which emerge only after the termination of the turbulent cascade. As suggested by hydrodynamics and by recent MHD numerical simulations, relaxation processes can occur during the turbulent cascade that will manifest themselves as local patches of equilibrium-like configurations. Using multi-spacecraft analysis techniques in conjunction with Cluster data, we compute the current density and flow vorticity and for the first time demonstrate that these localized relaxation events are observed in the solar wind. Such events have important consequences for the statistics of plasma turbulence.

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Cited by in corpus (5)

• Compressive Coherent Structures at Ion Scales in the Slow Solar Wind
• Kinetic range spectral features of cross-helicity using MMS
• Self-organisation and non-linear dynamics in driven magnetohydrodynamic turbulent flows
• Relaxation of the turbulent magnetosheath
• Evidence of Nonlinear Signatures in Solar Wind Proton Density at the L1 Lagrange point