Projectile channeling in chain bundle dusty plasma liquids: Wave excitation and projectile-wave interaction

Abstract

The microscopic channeling dynamics of projectiles in subexcitable chain bundle dusty plasma liquids consisting of long chains of negatively charged dusts suspended in low pressure glow discharges is investigated experimentally using fast video-microscopy. The long distance channeling of the projectile in the channel formed by the surrounding dust chain bundles and the excitation of a narrow wake associated with the elliptical motions of the background dusts are demonstrated. In the high projectile speed regime, the drag force due to wake wave excitation increases with the decreasing projectile speed. The excited wave then leads the slowed down projectile after the projectile speed is decreased below the resonant speed of wave excitation. The wave-projectile interaction causes the increasing projectile drag below the resonant speed and the subsequent oscillation around a descending average level, until the projectile settles down to the equilibrium point. Long distance projectile surfing through the resonant crest trapping by the externally excited large amplitude solitary wave is also demonstrated.

A scaling law for the dust cloud in radio frequency discharge under microgravity conditions

“…Usually, this particle called the projectile moves through the cloud with a supersonic or subsonic velocity. Such projectiles are generated using controlled mechanisms of acceleration 10,30 , or they can appear sporadically. 18,31 A strongly coupled Coulomb system like dust particles in the gas discharge plasma can be represented as a system of the Wigner-Seitz cells with a particle in the center of each cell.…”

Onset of cavity deformation upon subsonic motion of a projectile in a fluid complex plasma

“…In recent studies, attention was focused on tracer particles or projectiles moving through a cloud of complex plasma. Such projectiles are generated using controlled mechanisms of acceleration [11,20], or they can appear sporadically [19,21]. Projectiles moving with supersonic velocity lead to the formation of extended Mach cones; subsonic (slow) ones produce localized disturbances of surrounding particles.…”

Nonviscous motion of a slow particle in a dust crystal under microgravity conditions

“…Motion of small particles caused by the passage of a large particle has already been studied and used as a source of valuable information in the course of a ground-based experiment [22], where heavy particles were dropped down to the cloud of dust particles levitating in the plasma sheath region of a RF capacitive planar discharge. Trajectories of particles suspended in low pressure glow discharges have also been studied in [23]. Dust particles were arranged in chains, and a heavy particle falling between neighboring dust chain bundles caused the elliptical motions of the background dust particles.…”