Slow test charge response in a dusty plasma with Kappa distributed electrons and ions

By using the framework of kinetic model, the test charge driven response of a dusty plasma is evaluated in the presence of polarization force. The plasma containing electrons, singly ionized positive ions, and highly charged negative dust particulates is known as a dusty plasma, which can be perturbed by a test particle of charge qT moving with velocity vT along the z-axis. The polarization force purely comes from the high charging state of micron-sized dust particles, causing a deformation of shielding length due to density gradient and modifying the collective motion and particulates’ acceleration. The application of Fourier transformation technique to the set of dynamical equations may result in the shielded potential for a test charge with a modified dielectric constant. Several possibilities have been explored to evaluate the shielded potentials by imposing different conditions on the test charge speed in comparison with the thermal speeds of plasma species. It is found that the profiles of wakefield, Debye-Hückel and farfield (FF) potentials are strongly modified by the polarization force coefficient via the dust charging state and dust concentration. The present findings are useful in the study of strongly coupled dusty plasma, where micron-sized negatively charged dust grains are characterized by a high charging state.

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“…Thus, keeping the Landau damping term, we simplify Eq. 18 to obtain its reciprocal form (Ali and Eliasson, 2017), as…”

Section: Potential Distribution Around the Slow Test Chargementioning

confidence: 99%

“…Recalling Eqs 13, 19, it is found that there is only a difference in the finite dust temperature and polarization coefficient. By adopting the standard technique (Ali and Eliasson, 2017), the second part of the ES potential can be solved, as…”

Section: Potential Distribution Around the Slow Test Chargementioning

confidence: 99%

Test charge driven response of a dusty plasma with polarization force

Ali

Masood²,

Singh³

et al. 2022

Front. Astron. Space Sci.

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“…In 1968, for the first time, Vasyliunas [47] pointed out the implications of Kappa-df by fitting empirical data from solar wind and showed the significance of low values of electron spectral index, that is, κ s¼e $ 2 À 4: The effects of high energy tails have significantly modified the dispersive properties of waves and instabilities [48,49] in Lorentzian plasmas. Recently, Ali and Eliasson [50] investigated the impact of suprathermal hot electrons on the electrostatic potential of slowly moving test charge in a two-temperature electron plasma and extended the model for Lorentzian dusty plasmas [51].…”

Section: Power-law Lorentzian Distribution Function (Df)mentioning

confidence: 99%

Plasma Diagnostic Methods: Test Charge Response in Lorentzian Dusty Plasmas

Ali¹,

Al-Hadeethi²

2020

Selected Topics in Plasma Physics

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Different plasma diagnostic methods are briefly discussed, and the framework of a test charge technique is effectively used as diagnostic tool for investigating interaction potentials in Lorentzian plasma, whose constituents are the superthermal electrons and ions with negatively charged dust grains. Applying the space-time Fourier transformations to the linearized coupled Vlasov-Poisson equations, a test charge potential is derived with a modified response function due to energetic ions and electrons. For a test charge moving much slower than the dust-thermal speed, there appears a short-range Debye-Hückel (DH) potential decaying exponentially with distance and a long-range far-field (FF) potential as the inverse cube of the distance from test charge. The FF potentials exhibit more localized shielding curves for low-Kappas, and smaller effective shielding length is observed in dusty plasma compared to electron-ion plasma. However, a wakefield (WF) potential is formed behind the test charge when it resonates with dust-acoustic oscillations, whereas a fast moving test charge leads to the Coulomb potential having no shielding around. It is revealed that superthermality and plasma parameters significantly alter the DH, FF, and WF potentials in space plasmas of Saturn’s E-ring, where power-law distributions can be used for energetic electrons and ions in contrast to Maxwellian dust grains.

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“…In 1968, for the first time, Vasyliunas [47] pointed out the implications of Kappa-df by fitting empirical data from solar wind and showed the significance of low values of electron spectral index, that is, κ s¼e � 2 � 4: The effects of high energy tails have significantly modified the dispersive properties of waves and instabilities [48,49] in Lorentzian plasmas. Recently, Ali and Eliasson [50] investigated the impact of suprathermal hot electrons on the electrostatic potential of slowly moving test charge in a two-temperature electron plasma and extended the model for Lorentzian dusty plasmas [51].…”

Section: Power-law Lorentzian Distribution Function (Df)mentioning

confidence: 99%

Selected Topics in Plasma Physics

Singh¹

2020

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Slow test charge response in a dusty plasma with Kappa distributed electrons and ions

Cited by 5 publications

References 56 publications

Test charge driven response of a dusty plasma with polarization force

Test charge driven response of a dusty plasma with polarization force

Plasma Diagnostic Methods: Test Charge Response in Lorentzian Dusty Plasmas

Selected Topics in Plasma Physics

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