CC BY
27Complex Systems of Charged Particles and their Interactions with Electromagnetic Radiation 2019
AN INTERACTION OF CHARGED PARTICLES WITH DUST-ACOUSTIC
SOLITON
F.M. Trukhachev12, M.M. Vasiliev13, O.F. Petrov13
Joint Institute for High Temperatures of the Russian Academy of Sciences, Moscow, Russia,
e-mail: ftru@mail.ru
2State Institution of Higher Professional Education "Belarusian-Russian University, Mogilev, Belarus
3
Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region, Russia
In [1, 2], in the framework of MHD plasma models, the currents excited by ionic and electron-acoustic solitons in a plasma were investigated. It is shown that solitons lead to acceleration and transfer of charged particles of cold plasma populations in the direction of their motion. The currents excited by a cascade of solitons have a pulsed structure with a significant constant component. The spatial and temporal parameters of soliton currents were calculated. The proposed paper describes an experiment to study the dynamics of charged particles in a dusty plasma under conditions of developed dust-acoustic instability, which was developed to test the conclusions of the theory. The choice of dusty plasma as an object of study is due to the following considerations. First, dust-acoustic solitons can be described in the framework of MHD models used in [1, 2], differing only in spatial and temporal scales. Secondly, dusty plasma allows us to trace the dynamics of charged microparticles at the kinetic level, which greatly simplifies the design of the experiment. The experiment was performed in a low-pressure glow discharge at room temperature in neon [3]. The dynamics of individual particles in the soliton field was obtained on the basis of frame analysis of video filming of the wave process, which was conducted at a frequency of 500 fps.
In a glow discharge strata, a dust cloud was formed from charged monodisperse melamine-formaldehyde particles with a diameter of d = 4.25 ± 0.09 |im. Under the influence of the ion drag force in the cloud, dust-acoustic instability developed, which led to the formation of a solitary wave of large amplitude. The wave propagated from the anode to the cathode, bringing the plasma into a turbulent state. Analysis of the tracks of charged dust particles led to the conclusion that the soliton moves them in the direction of its motion by several Debye radii (up to ten). The speed of particles, the direction and magnitude of their movement are well described by the theory of soliton currents proposed in [1, 2]. Reaching the bottom edge of the dust cloud, the dust-acoustic soliton disintegrated, and the charged particles accelerated by it were thrown out of the cloud.
Thus, the property of solitons to accelerate charged particles and generate electric currents in a plasma is experimentally substantiated.
References
[1] F.M. Trukhachev, A.V. Tomov, 2016 Cosmic Research 54 (5) 351.
[2] F.M. Trukhachev et al. 2018 Technical Physics Letters 44 (6) 494.
[3] O.F. Petrov et al. 2018 JETP 126 (6) 842.
