Embedded Files
Fig. An ion hole creared by charged debris.
Driven chaos in plasma
So far as the dust-charge fluctuation in a complex plasma is concerned, we realise that in reality, the amount of charge acquired by the dust particles in a plasma is never constant, rather fluctuates continuously, owing to the changing electron and ion currents to the dust particles. While the semi-random nature of dust-charge fluctuation in time is quite natural and occurs due to the nonlinear nature of the plasma, theoretically it has been customary to assume these fluctuations to be closely following the plasma perturbation present in the system. As the amount of charge on a dust particle varies according to the electron and ion currents to the dust particle, one can also externally drive the fluctuation by varying these currents. One such situation is to expose the dust particles to intermittent (or periodic) bursts of charged particles which can cause the dust-charge to fluctuate. Due to the nonlinearity present in the system, there is a possibility that this driven dust-charge fluctuation can induce a chaotic response in the dynamics of the system. Though such a situation in the dust-acoustic regime has been considered by Momeni et al. in 2007, where they have shown a chaotic regime to exist in the oscillation of the dust density, the subject has been largely unexplored. The case of driven dust-charge fluctuation can also be compared to the effect of charged debris moving in a plasma, usually relevant in space plasmas, which has been a subject of some recent studies
Rinku Deka and Madhurjya P Bora, Physics of Plasmas 27, 043701 (2020)
Fig. Poincaré plots for the system in the chaotic regime. Subsequent panels are zoomed-out plots of the corresponding regions shown in the first plot.
Debris-induced nonlinearities in a PINI plasma
In this work, we explore different nonlinear structures excited by a moving charged debris in a multicomponent PINI plasma and also look at the similarities of their characteristics with di!erent experimental results. The complete plasma system is modeled using a forced Korteweg–de Vries (fKdV) equation and results from theoretical analysis are verified using a 1D multi-fluid flux-corrected transport simulation code (mFCT)
Rinku Deka and Madhurjya P Bora, Physics of Plasmas 25, 103704 (2018)
Fig. FCT simulation results showing evolution of a DSW in the precursor region over time for a negatively charged debris perturbation. Shaded region corresponds to the perturbation site.
Fig. FCT simulation results of propagation of nonlinear wave in a PINI plasma with an embedded external positively charged debris.
Page updated
Google Sites
Report abuse