Shocks propagate in a 2D dusty plasma with less attenuation than due to gas friction alone

Anton Kananovich,J Goree

doi:10.1063/5.0016504

Anton Kananovich, J Goree

Open Access

https://doi.org/10.1063/5.0016504

Copy DOI

Abstract

In a dusty plasma, an impulsively generated shock, i.e., blast wave, was observed to decay less than would be expected due to gas friction alone. In the experiment, a single layer of microparticles was levitated in a radio frequency glow-discharge plasma. In this layer, the microparticles were self-organized as a 2D solid-like strongly coupled plasma, which was perturbed by the piston-like mechanical movement of a wire. To excite a blast wave, the wire's motion was abruptly stopped, so that the input of mechanical energy ceased at a known time. It was seen that, as it propagated across the layer, the blast wave's amplitude persisted with little decay. This result extends similar findings, in previous experiments with 3D microparticle clouds, to the case of 2D clouds. In our cloud, out-of-plane displacements were observed, lending support to the possibility that an instability, driven by wakes in the ion flow, provides energy that sustains the blast wave's amplitude despite the presence of gas damping.

Highlights

A dusty plasma consists of electrons, ions, neutral gas, and microparticles.[1,2,3,4,5,6,7,8] Electrons and ions collect on the surface of the microparticles, which accumulate a large charge of thousands of elementary electron charges
We report an experiment with a blast wave in dusty plasma, where the primary topic is the attenuation of this blast wave and what that reveals about an input of energy
There might have been an unexpected lack of attenuation, according to Ivlev and Khrapak. We report another observation of little decay, for a blast wave, despite the dissipative effects of gas friction

Summary

Introduction

A dusty plasma consists of electrons, ions, neutral gas, and microparticles.[1,2,3,4,5,6,7,8] Electrons and ions collect on the surface of the microparticles, which accumulate a large charge of thousands of elementary electron charges. In the case of a continuously driven shock wave, there is a constant energy input into the system, so that the amplitude of the propagating shock is sustained and does not decay. A blast wave results from an impulsive deposition of energy, which has a finite time duration and occurs within a localized volume. After this initial impulsive energy input, the blast wave propagates without any further input of energy from an external source. We report an experiment with a blast wave in dusty plasma, where the primary topic is the attenuation of this blast wave and what that reveals about an input of energy

Results

Discussion

Conclusion