Speaker
Evgeny A. Lisin
Description
See the full Abstract at http://ocs.ciemat.es/EPS2018ABS/pdf/P5.3005.pdf
Correlational approach to study interparticle interactions in
complex plasmas
E.A. Lisin, O.S. Vaulina, O.F. Petrov
Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow, Russia
Moscow Institute of Physics and Technology, Dolgoprudny, Russia
A general approach to the correlational analysis of Brownian motion of strongly coupled
particles in open dissipative systems is described [1]. This approach can be applied to the
theoretical description of various non-ideal statistically equilibrium systems (including
non-Hamiltonian systems), as well as for the analysis of experimental data. In this report, we
consider an application of the correlational approach to the problem of experimental
exploring the wake-mediated nonreciprocal interactions in complex plasmas. For this, we
derive simple analytic equations, which allows one to calculate the derivatives of the
nonreciprocal interaction forces in a strongly coupled many-particle system as well as the
gradients of external field. These calculations use data on time-averaged correlations of
particles displacements and velocities, which are easily measured in an experiment. In the
examples of numerical simulations, we demonstrate that the proposed approach could be an
effective instrument in exploring the wake of a dust particle in a plasma. Unlike the previous
attempts to study the wake-mediated interactions in complex plasmas, our method does not
require a special design of the experimental setup and any external influences on a system,
pre-measurements and any assumptions about the form of interaction. It is based on
Brownian motion analysis only and can be used to study many-particle chain-like structures
in complex plasmas [1].
We also show the importance of taking dissipative and random processes into
account, without which consideration of a system with a nonreciprocal interparticle
interaction as linearly coupled oscillators leads to significant errors in determining the
characteristic frequencies in a system. We show that dissipative and random processes
determine the minimum value of the force derivative to which the particle “reacts”.
References
[1] E.A. Lisin, O.S. Vaulina, and O.F. Petrov, Physics of Plasmas 25(1), 013702 (2018)
