On the excitation of Ion Acoustic Soliton in quiescent plasma confined by multi-pole line cusp magnetic field

TL;DR

This study experimentally investigates ion acoustic solitons in quiescent argon plasma confined by a multi-pole cusp magnetic field, analyzing their properties, interactions, and the influence of magnetic field variations.

Contribution

It provides the first detailed experimental characterization of ion acoustic solitons in a multi-pole cusp magnetic field plasma device, including effects of magnetic field strength.

Findings

Solitons are excited and characterized in quiescent plasma.

Interaction of counter-propagating solitons confirms their solitary nature.

Magnetic field strength influences soliton amplitude and width.

Abstract

This paper presents the detailed study of the controlled experimental observation and characterization of Ion Acoustic soliton in the quiescent argon plasma produced by filamentary discharge and confined in a multi-pole line cusp magnetic field device named Multi-pole line Cusp Plasma Device (MPD). In this system, the electrostatic fluctuations are found to be less than 1%, a characteristic of quiescent plasma. Ion acoustic soliton has been excited in MPD, and its propagation velocity and width of them are measured experimentally and compared with the 1-D Korteweg-de Vries (KdV) equation. The interaction of two counter-propagating solitons is also investigated to confirm propagation's solitary nature further. After the successful characterization of ion-acoustic soliton, the effect of varying the cusp magnetic field on the propagation of ion-acoustic soliton has been studied. It is experimentally observed in MPD that the pole cusp magnetic field value influences the excitation and propagation of solitons. The soliton amplitude increases with the pole field up to some value Bp~0.6kG, then decreases with the further increase in field values. Meanwhile, the width of the soliton shows different behavior. The role of primary electron confinement by cusp magnetic field geometry has been used to explain the observed results.