Upper-hybrid wave driven Alfvenic turbulence in magnetized dusty plasmas

TL;DR

This paper investigates the nonlinear interaction between upper-hybrid and Alfven waves in magnetized dusty plasmas, revealing the emergence of solitary patterns, chaos, and turbulence, with potential relevance to Saturn's magnetosphere.

Contribution

It introduces a numerical model of coupled UH and AW wave dynamics in dusty plasmas, highlighting the formation of solitary patterns and turbulence due to modulational instability.

Findings

Coherent solitary patterns can be excited and saturated.

Spatiotemporal chaos arises from pattern collision and fusion.

Wave energy redistributes to higher harmonic modes, leading to turbulence.

Abstract

The nonlinear dynamics of coupled electrostatic upper-hybrid (UH) and Alfven waves (AWs) is revisited in a magnetized electron-ion plasma with charged dust impurities. A pair of nonlinear equations that describe the interaction of UH wave envelopes (including the relativistic electron mass increase) and the density as well as the compressional magnetic field perturbations associated with the AWs is solved numerically to show that many coherent solitary patterns can be excited and saturated due to modulational instability of unstable UH waves. The evolution of these solitary patterns is also shown to appear in the states of spatiotemporal coherence, temporal as well as spatiotemporal chaos due to collision and fusion among the patterns in stochastic motion. Furthermore, these spatiotemporal features are demonstrated by the analysis of wavelet power spectra. It is found that a redistribution of wave energy takes place to higher harmonic modes with small wavelengths which, in turn, results into the onset of Alfvenic turbulence in dusty magnetoplasmas. Such a scenario can occur in the vicinity of Saturn's magnetosphere as many electrostatic solitary structures have been observed there by the Cassini spacecraft.