Wave pressure and energy cascade rate of kink waves computed with Elsasser variables

Abstract

Numerical simulations have revealed a new type of turbulence of unidirectional waves in a plasma that is perpendicularly structured (Magyar et al. 2017), named uniturbulence. For this new type of turbulence, the transverse structuring modifies the upward propagating wave to have both Elsasser variables, leading to the well-known perpendicular cascade. In this paper, we study an analytical description of the non-linear evolution of kink waves in a cylindrical flux tube, which are prone to uniturbulence. We show that they lead to a non-linear cascade for both propagating and standing waves. We calculate explicit expressions for the wave pressure and energy cascade rate. The computed damping rate τ/P depends on the density contrast of the flux tube and the background plasma and is inversely proportional to the amplitude of the kink wave. The dependence on the density contrast shows that it plays a role especially in the lower solar corona. These expressions may be added in Alfven wave driven models of the solar atmosphere (such as AWSOM, van der Holst et al. 2014), modifying it to UAWSOM (Uniturbulence and Alfven Wave Solar Model).

References in corpus (6)

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• Three-dimensional simulation of the fast solar wind driven by compressible magnetohydrodynamic turbulence
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Cited by in corpus (11)

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• Three-dimensional simulations of the inhomogeneous Low Solar Wind
• A statistical study of propagating MHD kink waves in the quiescent corona
• Propagating Kink Waves in an Open Coronal Magnetic Flux Tube with Gravitational Stratification: Magnetohydrodynamic Simulation and Forward Modelling
• The dynamics and observability of circularly polarized kink waves
• Unveiling the True Nature of Plasma Dynamics from the Reference Frame of a Super-penumbral Fibril
• Uniturbulence and Alfven wave solar model
• Kelvin-Helmholtz instability and heating in oscillating loops perturbed by power-law transverse wave drivers
• How transverse MHD wave-driven turbulence influences the density filling factor in the solar corona?
• High-Frequency Magnetohydrodynamic Waves with Substantial Energy in the Solar Polar Corona