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Plasmas 28, 053505 (2021).10.1063/5.0045947 12 J. Moreno, A. Khodaee, D. Okerstrom, M. P. Bradley, and L. Couëdel, " Time-resolved evolution of plasma parameters in a plasma immersion ion implantation source", Phys. However, there is still a lack of understanding of the plasma parameters in the complex mixture gas (radical/ion species, electron/ion energy distributions, temperature, etc.) and plasma physics (electron heating dynamics, electron kinetics, wave-particle interaction, dust plasma characteristics, etc.). The "Plasma Physics and Science in Current and Next Generation Semiconductor Process" Special Topic in I Physics of Plasmas i consists of articles on research presented at The 8th International Conference on Microelectronics and Plasma Technology (ICMAP), which was held in Hwaseong, South Korea, January 17-20, 2021.[1] The "Plasma Physics and Science in Current and Next Generation Semiconductor Process" Special Topic is devoted to understanding such plasma source, plasma parameters, plasma-surface interaction, and processing results in semiconductor process and its related fields, and to bring new insight from theory and experiment for the next generation of plasma process techniques. [Extracted from the article]

In this paper, the dust acoustic wave is studied in conditions where the dust temperature is not constant. This model includes negatively charged dust particles and thermal ions. The reductive perturbation technique is used and the new point in this study is the nonuniformity of the plasma temperature. The nonconstancy of the temperature is entered as a first-order perturbation in the calculations, and finally the modified Korteweg–de Vries (mKdV) equation is derived. The solution of the modified KdV equation clarifies the change in soliton shape of the wave when it moves in the perturbation plasma. We show how the soliton wave undergoes deformation and amplitude reduction during propagation when it encounters a region with a different temperature. The output of this research can be effective to better understand the wave behavior in a real plasma with nonuniform temperature. [ABSTRACT FROM AUTHOR]

In this paper, the Crank-Nicholson method is applied to solve the one-dimensional nonlinear Burgers' equation in warm, dusty plasmas with dust charge variation. After obtaining numerical results, a thorough analysis is conducted and compared against analytical solutions. On the basis of the comparison, it is evident that the numerical results obtained from the analysis are in good agreement with the analytical solution. The error between the analytical and numerical solutions of the Burgers' equation is calculated by two error norms, namely L2 and L∞. A Von-Neumann stability analysis is performed on the present method, and it is found to be unconditionally stable according to the Von-Neumann analysis. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the effect of different amounts of filler on concrete properties. An experimental approach has made it possible to develop a construction product made from limestone dust, which is considered waste. This paper presents an experimental study on the prospects of using a mixture of waste limestone powder for the manufacture of an economical and lightweight composite as a building material. This paper also presents the results of research on the possibility of using limestone dust as an aggregate in the production of concrete with lightweight aggregates. In this way, different amounts of limestone dust were used. Tests were conducted on concrete to replace 30, 50, and 70% by weight of coarse aggregate. The mechanical properties of concrete mixtures with high proportions of limestone dust were examined. The achieved compressive strength, flexural strength, and unit weight correspond to current international standards. [ABSTRACT FROM AUTHOR]

When a high-speed spacecraft returns to the atmosphere, a plasma sheath is formed on its surface. This causes electromagnetic waves to be reflected and absorbed. In this paper, a single-layer medium matrix transport model is used to derive expressions for the reflectivity, transmittance and attenuation values of electromagnetic waves. The electron density distribution is also modelled and the effects of electron density, plasma thickness, particle collision frequency, and magnetic field strength on the reflectivity as well as the transmittance of electromagnetic waves are discussed visually using three-dimensional images. Finally, the reflectivity and transmittance of electromagnetic waves propagating in a dust-free plasma are analyzed, with emphasis on comparing the effects of different media on the reflectivity and transmittance of electromagnetic waves. In summary, the relevant research can provide some theoretical references for propagation science. [ABSTRACT FROM AUTHOR]

The first true common volume observations of the PMSE source region with 4 radars are presented in this paper. Radar frequencies of 8, 56, 224, and 930 MHz are used in this study. Three days of experimental observations at EISCAT are presented. Numerical simulations of mesospheric dusty/ice plasma associated with the observed radar frequencies are presented. The effect of neutral air turbulence on the generation and strength of plasma density perturbations associated with PMSE using four radar frequencies and in the presence of various dust parameters is investigated. Using the model it is shown that the well‐known neutral air turbulence in the presence of heavy dust particles and neutral air turbulence combined with dust density (dusty turbulence) can largely explain the observed radar cross‐section at four radar frequencies. The effect of neutral air turbulence amplitude along with dust charging and diffusion in the presence of various dust parameters is investigated using the computational model. Specifically, the response of diffusion to charging time scales, plasma density fluctuation amplitude and background dusty plasma parameters are discussed. Several key parameters in the dusty plasma responsible for the PMSE observations are determined. Qualitative comparison of radar echo strength at 4 frequencies with numerical results is provided. Unlike the previous studies that required large dust particles of 20 nm for PMSE formation, the present work demonstrates the possibility of small dust particles to explain the experimental observations. Key Points: The first simultaneous four radar frequency observation of the PMSE is presentedThe computational results and observations validate the fossil theory proposed to 14 produce the PMSEThe effect of initial turbulence amplitude along with dust charging and diffusion 16 in the presence of various dust parameters is investigated for the first time [ABSTRACT FROM AUTHOR]

The use of heat transfers in heat exchangers, nuclear cooling, solar collectors, and electrical devices is crucial nowadays. Hybrid nanofluid can be used in these applications to get the best results because it encourages efficient heat transmission compared to conventional fluid. The effect of radiation and an unsteady Carreau hybrid fluid in addition to non-Fourier heat flux over a shrinking sheet is discussed in this paper. Using similarity transformations, the newly developed system of partial differential equations (PDEs) is converted into a set of ordinary differential equations (ODEs), that are next numerically addressed by utilizing shooting approach and the Runge–Kutta (RK) method. Tables and graphs are used to present utilizing the computational findings for nondimensional temperature, velocity, heat transfer rate, and friction between fluid and hybrid nanoparticles. Additionally, for certain physical factors, the physical quantities in numerical values were also presented (such as the friction factor and local Nusselt number). We made a restricted case comparison between the current findings and the body of prior research. Our finding confirms that the temperature profile is strengthened by the heat generation parameter and the effect of radiation. The porosity parameter decelerates the momentum boundary layer thickness near the plate. [ABSTRACT FROM AUTHOR]

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In this paper, we investigate the behavior of dust ion acoustic solitary waves (DIASWs) with arbitrary amplitudes in a magnetized anisotropic dusty plasma that includes inertial hot ion fluid, electrons following a Kappa distribution, and negatively charged dust particles in the background. An ambient magnetic field aligns with the x-direction, while the wave propagation occurs obliquely to the ambient magnetic field. In the linear regime, two distinct modes, namely fast and slow modes, are observed. We employ the Sagdeev pseudo-potential method to analyze the fundamental properties of arbitrary amplitude DIASWs. Additionally, we examine how various physical parameters influence the existence and characteristics of symmetric planar dust ion acoustic solitary structures (DIASs). The characteristics of the solitary structures are greatly influenced by the dust concentration, the electrons superthermality (spectral) index, the obliquity parameter, the magnetic field, the parallel ion pressure and the perpendicular ion pressure. The results show that the amplitude and width of both compressive and rarefactive DIASWs are sensitive to the degree of electron superthermality and dust concentration. Additionally, it is shown that the propagation features of DIASWs are highly affected by the parallel component of ion pressure as compared to perpendicular component of ion pressure. [ABSTRACT FROM AUTHOR]

Melamine formaldehyde microspheres are widely used in dusty plasma experiments for their monodispersity, sphericity, low mass density, and well defined sizes. This paper summarizes problems that were encountered in numerous applications of these grains in different laboratory simulations. and the already published results are discussed in view of new experiments. The main results of this paper are connected with changes of the grain mass due to the decreased pressure and/or increased temperature and variations of the grain dimensions, its shape, and mass density under electron or ion bombardments. By contrast to the work function estimated from field emission properties, we have found the photoelectric work function (4.5 eV) being close to that expected. A sputtering of the grains using a 30-keV ion beam revealed their unexpected heterogeneity. [ABSTRACT FROM AUTHOR]

This is the second paper in the series about the design and operation of LENR reactors, to be followed by Part 5C on the same subject. While in Part 5A we mainly discussed the reactors based on electrolysis that were at the center of research for decades, a new field of reactors based on dusty plasma was also discussed. We move into a new area in Part 5B: LENR reactors based on quasi-particles. Though plasmon polaritons and condensed plasmoids were frequently mentioned in all previous parts, we shall move towards their practical applications. First the landscape of mainstream transient plasma research is shown. There the streamers of corona and spark discharges are known to produce heavy negative quasi-particles. However, they have never been tested for catalytic nuclear fusion, just as chemical catalysts. We shall review spark related research, as this area is shown to induce fusion effects. Most of the results have been published in peer-reviewed journals, like Fusion Technology. The most important results have come from the papers of Matsumoto, Karabut and Dufour. The most important patents were granted to Shoulders. These results were published mainly in the 1990s, the "golden age" of LENR research. Based on these results and insights, we move back a hundred years, to the research of Tesla. Judging by the shape of his discharge tubes, it is plausible that Tesla had a practical application of the results published 100 years later. In Part 5C, inventions after the 1930s will be analyzed. [ABSTRACT FROM AUTHOR]

The center of this paper is to establish the generalized variational structure (GVS) of the (3 + 1) -dimensional Zakharov–Kuznetsov–Burgers equation (ZKBe) by taking advantage of the Semi-inverse method (SIM). Two different GVSs are extracted and the derivation process is presented in detail. The extracted GVSs reveal the energy conservation law and can offer some new insights on the study of the variational method. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive exploration of shock waves in a dusty plasma, incorporating the dynamics of inertial dust and ions with Maxwellian distributed electrons. By deriving the Korteweg-de Vries-Burgers (KdV-B) equation and by using its standard solution we analyze the characteristics of the shock front under varying parameters. Furthermore, we conduct a phase plane analysis to elucidate the system's behavior and dynamics by tuning in the parameters that provide various types of perturbation in the system. The investigation sheds light on the intricate behavior of shock waves in dusty plasmas and contributes valuable insights to the understanding of plasma dynamics. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Dust Acoustic Solitary Waves in Dusty Plasma With Nonthermal Ions," by Frank Verheest and colleagues that was published in the February 11, 2010 issue.

The effect of dust grain pressure on the head‐on collision of two dust‐acoustic solitary waves in non‐magnetized, collisionless, and strongly coupled dust plasma has been investigated [J. Plasma Phys. (2020), 86, 905,860,111]. In this paper, the model is augmented by incorporating the ion drag force on dust grains. By way of the extended perturbation method of Poincaré‐Lighthill‐Kuo, Korteweg‐de Vries equations are derived. The wave characteristics along with the phase shifts after the head‐on collision are analytically established and numerically assessed. It revealed a non‐negligible decrease in the wave amplitude and the phase shift. [ABSTRACT FROM AUTHOR]

Applicability limit of the well-known phase diagram of dusty plasmas in κ-Γ plane (κ is structural parameter and κ is parameter of Coulomb nonideality) is under discussion. Existence of extensive domains with violation of plasma thermodynamic stability conditions (i.e., with negative isothermal compressibility) was also claimed if one uses well-known nonideal equations of state by (Hamaguchi S. et al., Phys. Rev. E, 1997) and (Khrapak S. et al., Phys. Rev. E, 2014). This paper is devoted to analysis of a range of applicability for basic assumption in Hamaguchi's phase diagram, i.e., linearized (Debye) screening of macroions by microions, which leads to the Yukawa form for effective interactions between macroions. Parameters of nonlinear screening for macroions were calculated within differential Poisson--Boltzmann equation. Two effects were revealed as a result of such calculations: 1) decomposition of all microions onto two subclasses, free and bound ones, and 2) significant reduction of effective charge Z* of initial bare macroion Z under nonlinear screening by small high-density envelope of bound ions. This effect leads to a renormalization of initial Γ and κ into Γ* and κ* (Γ* < Γ, κ* < κ). The main physical assumption is phase states of complex plasma under nonlinear screening, which are still the same as on the initial phase diagram, but in κ*-Γ* plane instead of κ-Γ one. Corresponding calculated shifts of phase states are discussed and illustrated. [ABSTRACT FROM AUTHOR]

Aiming to delineate the physical framework of blazars, we present an effective method to estimate four important parameters based on the idea proposed by Becker & Kafatos, including the upper limit of central black hole mass M, the Doppler factor δ, the distance along the axis to the site of the Îł -ray production d (which then can be transformed into the location of Îł -ray-emitting region R Îł ) and the propagation angle with respect to the axis of the accretion disk Φ. To do so, we adopt an identical sample with 809 Fermi-LAT-detected blazars which had been compiled in Pei et al. These four derived parameters stepping onto the stage may shed new light on our knowledge regarding Îł -ray blazars. With regard to the paper of Becker & Kafatos, we obtain several new perspectives, mainly in (1) putting forward an updated demarcation between BL Lacs and FSRQs based on the relation between broad-line region luminosity and disk luminosity both measured in Eddington units, i.e., L disk/ L Edd = 4.68 Ă— 10âˆ'3, indicating that there are some differences between BL Lacs and FSRQs on the accretion power in the disk; (2) proposing that there is a so-called “appareling zone,” a potential transition field between BL Lacs and FSRQs where the changing-look blazars perhaps reside; (3) the location of Îł -ray emission region is principally constrained outside the broad-line region, and for some BL Lacs are also away from the dusty molecular torus, which means the importance of emission components in the jet. [ABSTRACT FROM AUTHOR]

Due to the small charge-to-mass ratio of dust particles, it is often necessary to use large magnetic fields of B ≥ 1 T, in order to observe the influence of magnetic forces in laboratory dusty plasmas. However, when experiments are performed at high magnetic fields in capacitively coupled, radio frequency discharges used for these dusty plasma experiments, the plasma is often observed to form filamentary structures between the electrodes that are aligned to the external magnetic field which disrupt the uniformity of the plasma and adversely impact some of our dusty plasma experiments. Recent experiments performed in the Magnetized Dusty Plasma Experiment device seek to identify and characterize these filamentary structures. This paper discusses the morphology of several distinct filamentary modes that are formed in low temperature argon plasmas. Three different spatial modes of filaments that appear to be strongly dependent on the magnetic field and neutral pressure are identified. There is strong evidence that each spatial mode has a threshold condition that is dependent on the ion Hall parameter. The criteria for the formation of the filaments are shown to be consistent with predictions of recent numerical simulations. [ABSTRACT FROM AUTHOR]

Different kinds of waves and instabilities in the F-region of the ionosphere excited by the relative streaming of the dust beam to the background plasma are studied in the present paper. The dispersion relations of different waves are obtained on different time scales. It is found from our numerical results that there are both a stable upper hybrid wave on the electron vibration time scale and a stable dust ion cyclotron wave on the ion vibration time scale. However, the chaotic behaviour appears on the dust particles vibration time scale due to the relative streaming of the dust particles to the background plasma. Such instabilities may drive plasma irregularities that could affect radar backscatter from the clouds. [ABSTRACT FROM AUTHOR]

A theoretical investigation is presented to explain the formation and characteristics of relaxed equilibrium structures in a three-component dusty plasma within Saturn's atmosphere, composed of negatively charged dust particles, electrons, and ions. The Quadruple Beltrami equation is derived by utilizing the vortex dynamic equations along with the current density. Solutions for the higher Beltrami states are obtained in two different modes, a simple rectangular geometry and a coplanar rectangular geometry, to explore the characteristics of relaxed structures within the Saturn magnetosphere and its rings. The solutions are depicted through some plots by varying the Beltrami parameters and the densities of the plasma species. It is observed that only paramagnetic structures are formed in the coplanar geometry, while variations in the Beltrami parameters and plasma species densities significantly affect the magnetic characteristics of the relaxed structures in a simple rectangular geometry. This paper will provide an important contribution to understand the atmospheric vortical structures developed in different astronomical bodies that have double or more than double configurations, such as Saturn's rings, Jupiter magnetosphere, Uranus, Neptune, etc. [ABSTRACT FROM AUTHOR]

Since the first automatic missions to the Moon, the activity of dust particles from atmosphereless bodies has been recorded. Since then, a lot of theoretical and experimental studies of this effect have been carried out, but at present there is no clear understanding of the influence of external actions on the dynamics of this phenomenon. This paper presents the results of experiments to determine the effect of hard UV radiation on the activity of dust particles, which makes a significant contribution to particle dynamics. The result of determining the conditions for particle removal from the surface is in accordance with theoretical calculations. [ABSTRACT FROM AUTHOR]

In this paper, we present experimental observation of the transition of a 2D dust crystal to a non-equilibrium solid–liquid phase coexistence state. The experiments have been carried out in an L-shaped dusty plasma experimental device in a DC glow discharge argon plasma environment. Initially, a monolayer crystalline structure is formed, which is later transformed to a two-phase coexistence state using the background neutral pressure as a control parameter. Self-excited horizontal oscillations are found in the center of the monolayer prior to the appearance of the coexistence state. It is observed that a molten center coexists with a solid periphery. Various structural, thermodynamic, and dynamical quantities are used to characterize the phase state. The surface tension at the solid–liquid circular interface is also determined. A detailed parametric study is made to delineate the existence region of such a state. It is found that melting caused at the core is due to the onset of a localized Schweigert instability in the presence of a few stray particles beneath the top layer in that region. [ABSTRACT FROM AUTHOR]

In this paper, variable coefficients mKdV equation is examined by using Painlevé analysis and auto-Bäcklund transformation method. The proposed equation is an important equation in magnetized dusty plasmas. The Painlevé analysis is used to determine the integrability whereas an auto-Bäcklund transformation technique is being explored to derive unique family of analytical solutions for variable coefficients mKdV equation. New kink–antikink and periodic-kink- type soliton solutions have been determined successfully for the considered equation. This paper shows that auto-Bäcklund transformation method is effective, direct and easy to use, and used to determine the analytic soliton solutions of various nonlinear evolution equations in the field of science and engineering. The results are plotted graphically to signify the potency and applicability of this proposed scheme for solving the above considered equation. The obtained results are in the form of soliton-like solutions, solitary wave solutions, exponential and trigonometric function solutions. Therefore, these solutions help us to understand the potential and physical behaviors of the proposed equation. [ABSTRACT FROM AUTHOR]

In this paper, we have investigated the effect of secondary electron emission on nonlinear propagation of dust acoustic waves in a complex plasma considering equilibrium dust charge positive and compared the results with those obtained in our recently published paper [Bhakta et al., Phys. Plasmas 24, 023704 (2017)] where the equilibrium dust charge was negative. In both papers, primary and secondary electrons are assumed to follow Boltzmann distribution with separate electron temperatures, ions are also Boltzmann distributed and charged dust grains are inertial. Change in the nature of dust charge (negative to positive) gives rise to some opposite behaviour of wave propagation characteristics in dusty plasma when dust grains are charged by secondary electron emission mechanism. Both adiabatic and nonadiabatic dust charge variations have been separately considered in both the papers. The investigation in this paper shows that compressive dust acoustic soliton propagates in case of adiabatic dust charge variation whose amplitude increases and width decreases with an increase in the strength of the secondary electron emission. This is in contrast to the case of negative equilibrium dust charge which confirms the existence of rarefied dust acoustic soliton with decreasing amplitude and increasing width for an increase in the strength of the secondary electron emission. Nonadiabaticity of dust charge variation in both cases generates dust acoustic shock wave which is oscillatory for weak nonadiabaticity and monotonic for strong nonadiabaticity. For positive equilibrium dust charge, the amplitude of both oscillatory and monotonic shocks increases and oscillation of the oscillatory shock persists longer for stronger secondary electron emission. On the other hand for negative equilibrium dust charge, the amplitude of both the oscillatory and monotonic shocks diminishes with increasing secondary electron emission. Published by AIP Publishing. [ABSTRACT FROM AUTHOR]

In this paper, non-linear propagation of oscillatory and monotonous DIA shocks in dusty plasma with dust charge fluctuations and small isothermal deviation of electrons is considered. The modified-Korteweg-de Vries–Burger (m-KdVB) equation can be derived by using the reductive perturbation (R-P) method. The variational principle and the conservation laws of the m-KdVB equation are constructed by introducing two special functions. A nonlinear self-adjoint classification of the m-KdVB equation is presented. Based on the Ibragimov's theorem, conservation laws for m-KdVB equation are established. We also study the m-KdVB equations by improved tan ψ (χ) 2 -expansion method. Abundant dark, singular and periodic optical solitons solutions of the model are constructed. Furthermore, additional graphical simulations were performed using mathematica to see the behavior of these solutions. With the help of bifurcation theory of planar dynamical systems, we study bifurcation and phase portrait analysis of traveling wave solution of the m-KdVB equation. [ABSTRACT FROM AUTHOR]

Cellulose is an abundant natural polymer and is thus promising for enforcing biobased plastics. A broader application of cellulose fibers as a filler in polymer composites is limited because of their hydrophilicity and hygroscopicity. The recent scientific literature on plasma methods for the hydrophobization of cellulose materials is reviewed and critically evaluated. All authors focused on the application of plasmas sustained in fluorine or silicon-containing gases, particularly tetrafluoromethane, and hexamethyldisiloxane. The cellulose materials should be pre-treated with another plasma (typically oxygen) for better adhesion of the silicon-containing hydrophobic coating. In contrast, deposition of fluorine-containing coatings does not require pre-treatment, which is explained by mild etching of the cellulose upon treatment with F atoms and ions. The discrepancy between the results reported by different authors is explained by details in the gas phase and surface kinetics, including the heating of samples due to exothermic surface reactions, desorption of water vapor, competition between etching and deposition, the influence of plasma radiation, and formation of dusty plasma. Scientific and technological challenges are highlighted, and the directions for further research are provided. [ABSTRACT FROM AUTHOR]

Ladle slag is a byproduct formed during the ladle refining stage of steel making. It is a dusty material that has been considered industrial waste. Technical advancements towards a sustainable industry led to the development of different applications for ladle slag. Depending on the processing methods during the steel slag production and the weathering of the slag post‐production, the elemental composition of the steel slag largely varies. Owing to this, its characteristics cannot be generalized and specific applications depending on the sources are developed. It is generally used in construction materials, soil rejuvenation, and CO2 capture. This paper reviews the production process, the mineralogical and morphological properties, stabilization techniques, and the applications of ladle furnace (LF) slag. One of the prime focuses of waste remediation and sustainable industry is to find meaningful ways to turn waste into products. In this respect, a comprehensive review of the properties of LF slag and its current application will help provide a framework for the development of future sustainability goals. With increased slag usage, the ladle refining process of steelmaking can be turned into a more carbon‐neutral process. [ABSTRACT FROM AUTHOR]

This paper presents a new approach to determining the dimensions of particles that can be lifted to a coma by the sublimation flux of water ice. Due to the diverse colour of the cometary surfaces, in the presented calculations we take into account the influence of the reflectance coefficient (hemispherical albedo) on the size of particles lifted from the surface of the nucleus. A Cary 5000 spectrometer was used to measure hemispherical albedo. Spectroscopic measurements used dust particles that consisted of pure silicate or were a mixture of pure silicate and organic compounds such as charcoal, soot, and ash. In addition, these admixtures acted as a means of darkening the tested sample. Depending on the colour of the sample and the wavelength, the measured value of hemispherical albedo oscillated in the range from 4.93 per cent to 48.65 per cent. A thermodynamic model of cometary matter emission was developed based on the results of hemispherical albedo measurements. The performed numerical simulations show that the temperature decreases with the increase of the hemispherical albedo, which translates into the sublimation flux and the dynamics of the dust-ice particles present on the surface of the cometary nucleus. Taking into account the extreme values of the hemispherical albedo, the differences in the size of particles carried away from the surface of the nucleus are in the order of centimeters. [ABSTRACT FROM AUTHOR]

In this paper, we have presented our investigation on the characteristic of nonlinear dust acoustic waves (DAWs) propagating in an inhomogeneous collisionless magnetized dusty plasma (MDP). In this problem, we have considered a collisionless plasma consisting of nonthermal ions, non-extensive electrons and negatively charged dust grains. Using the reductive perturbation theory (RPT) we have derived the modified Zakharov-Kuznetsov (m-ZK) equation. The solution of m-ZK equation indicates the nonlinear characteristics of the DASWs in plasma. Our investigation also predicts how the amplitudes of nonlinear DASWs are significantly modified due to the influence of magnetic field, non-extensive electrons and inhomogeneity parameters in plasma. The results obtained in this investigation may be useful for understanding the propagation characteristics and modification of structures of nonlinear waves in both laboratory and astrophysical plasmas. [ABSTRACT FROM AUTHOR]

This paper presents the results of a recent study of the interaction between charged dust particles and plasma ions through the electrostatic and ion drag forces in a dc glow discharge plasma. Measurements of the dust particles motion are carried out using particle image velocimetry (PIV). When an electrostatic perturbation is applied to the dust cloud, the particle motion, in response to the perturbation, is shown to reverse direction as the gas pressure is increased. An analysis of the dust particle motion and background plasma parameters suggests that there is a change in the equilibrium position and competition between the electrostatic force and the ion drag force on the particles that lead to the asymmetric motion of the cloud. The ion drag and electric forces on the dust particles are calculated at each pressure using detailed measurements of the plasma parameters, as measured by a single Langmuir probe. The analysis of these measurements suggests that the reversal of direction is a result of the change in the electric field in the plasma, but that the effectiveness of the perturbation at displacing the dust cloud is controlled by the ion drag force. [ABSTRACT FROM PUBLISHER]

Dispersion is one of the important characteristics of dusty plasma. In this paper, the real and imaginary parts of the complex refractive index of dusty plasma are first deduced and verified by the Kramers–Kronig dispersion relation. And then, the dependence of dispersion ability on the temperature, pressure, angular frequency of incident electromagnetic wave, as well as the number density, radius, and charge of dust particles is given. Finally, the theoretical results indicate that: 1) the dispersion ability decreases with the increase of angular frequency; 2) the dispersion ability monotonically varies with the pressure approximately, but nonmonotonically varies with the temperature; and 3) the dispersion ability monotonically increases with the increase of dust particle’s charge, but nonmonotonically changes with the number density and radius of dust particles. In particular, the involved physical explanations are proposed. [ABSTRACT FROM AUTHOR]

This paper reports the levitation of micro-organisms in the sheath of radio-frequency (RF) plasma. Based on simple force-balance calculations, the required electric field for the levitation of micro-organisms has been estimated. It is predicted that micro-organisms could levitate at the periphery of the sheath. Experimental results demonstrate the levitation of two species of bacillus micro-organisms Escherichia coli (E. coli) and Klebsiella pneumoniae in an RF plasma. The almost monodiverse Klebsiella pneumoniae levitating in the RF plasma formed an ordered state similar to a 2-D Coulomb crystal. Diverse E. coli particles demonstrate the tendency that the levitating height of micro-organisms decreases as the radius of particles increases. Levitating micro-organisms in plasmas can be referred as dusty plasmas. [ABSTRACT FROM AUTHOR]

In dusty plasmas, dust particles are levitated by balance of forces inward to the plasmas (typically corresponding to electrostatic force) and outward from the plasmas (ion drag force) as well as gravity. The balance of the forces tends to make a region free from dust particles, so-called void at the center of the plasmas. This paper made it clear in measurements of ion density and electron temperature with a double-probe method that the void was a region involving ionization. The dust particles were distributed in the other region diffusion dominant for electrons and ions. The void is shown to be reduced by restricting the region involving ionization. [ABSTRACT FROM AUTHOR]

The Plasma Wave Investigation (PWI) aboard the BepiColombo Mio (Mercury Magnetospheric Orbiter, MMO) will enable the first observations of electric fields, plasma waves, and radio waves in and around the Hermean magnetosphere and exosphere. The PWI has two sets of receivers (EWO with AM2P, SORBET) connected to two electric field sensors (MEFISTO and WPT) and two magnetic field sensors (SCM: LF-SC and DB-SC). After the launch on October 20, 2018, we began initial operations, confirmed that all receivers were functioning properly, and released the launch locks on the sensors. Those sensors are not deployed during the cruising phase, but the PWI is still capable performing magnetic field observations. After full deployment of all sensors following insertion into Mercury orbit, the PWI will start its measurements of the electric field from DC to 10 MHz using two dipole antennae with a 32-m tip-to-tip length in the spin plane and the magnetic field from 0.3 Hz to 20 kHz using a three-axis sensor and from 2.5 kHz to 640 kHz using a single-axis sensor at the tip of a 4.5-m solid boom extended from the spacecraft's side panel. Those receivers and sensors will provide (1) in-situ measurements of electron density and temperature that can be used to determine the structure and dynamics of the Hermean plasma environment; (2) in-situ measurements of the electron and ion scale waves that characterize the energetic processes governed by wave–particle interactions and non-MHD interactions; (3) information on radio waves, which can be used to remotely probe solar activity in the heliocentric sector facing Mercury, to study electromagnetic-energy transport to and from Mercury, and to obtain crustal information from reflected electromagnetic waves; and (4) information concerning dust impacts on the spacecraft body detected via potential disturbances. This paper summarizes the characteristics of the overall PWI, including its significance, its objectives, its expected performance specifications, and onboard and ground data processing. This paper also presents the detailed design of the receiver components installed in a unified chassis. The PWI in the cruise phase will observe magnetic-field turbulence during multiple flybys of Earth, Venus, and Mercury. After the Mercury-orbit insertion planned at the end of 2025, we will deploy all sensors and commence full operation while coordinating with all payloads onboard the Mio and MPO spacecraft. [ABSTRACT FROM AUTHOR]

The head-on collision between two dust-acoustic solitary waves in a non-magnetized, collisionless and strongly coupled dust plasma has been studied. The application scope of the analytical solution of the head-on collision is given in the present paper by using the particle-in-cell simulation method. It is noted that the analytical results are valid if the amplitudes of both of the solitary waves are small enough. The effects of the coupling parameters on both the head-on collision and the waveform are also studied in the present paper. [ABSTRACT FROM AUTHOR]

Energy absorption of electromagnetic (EM) waves in collisional dusty plasmas is attracting much attention from researchers due to its applications in many fields, such as plasma antennas, blackout research during reentry, plasma stealth technology, and the design of microwave transmission in plasmas. In this paper, the propagation characteristics, in particular, the energy absorption effects of EM waves in partially ionized unmagnetized collisional dusty plasmas, are investigated. The results show that the effective energy absorption of EM waves is mainly due to the interaction between electrons and waves, and the plasmas with proper collisional frequencies can be used as a broadband frequency EM wave absorption medium with moderate absorption efficiency. Quantitative analyses of the characteristics of the EM waves that propagate in the collisional dusty plasmas are also included in this study. [ABSTRACT FROM AUTHOR]

This special Issue focuses on the field of dusty plasmas or also referred to as complex plasmas. Most of the papers were presented at the 8th International Conference on the Physics of Dusty Plasmas (8 ICPDP, ), which was hosted by Charles University and held in Prague, Czech Republic, on May 20–25, 2017. We would like to join the continuous tradition of special issues of the IEEE Transactions on Plasma Science from April 1994, 2001, 2004, 2007, 2010, 2013, and 2016 associated with the other most important triennial meeting for the community, the Workshop on the Physics of Dusty Plasmas. We believe that these two conferences and papers connected to them reflect the current state of the art and progress in the field. [ABSTRACT FROM AUTHOR]

This paper deals with the formation of nanoparticles in a pulsed discharge. Experiments are performed in a capacitively coupled discharge operated in a mixture of argon and acetylene. The paper focuses especially on the influence of the pulse frequency on the dust formation. The experiments reveal the existence of a rather narrow frequency band that separates a frequency region with no dust formation from a frequency region where dust formation occurs. The decisive point in the observations is that a small change in the pulse frequency (from 700 to 725 Hz) is enough to induce or, respectively, suppress the formation of dust particles. The experimental results are discussed by means of a simple model that allows one to calculate the density of negative ions (C2H-, C4H-, etc.) as a function of the pulse frequency. [ABSTRACT FROM AUTHOR]

Dusty plasmas are electrically quasi-neutral media that, along with electrons, ions, neutral gas, radiation, and electric and/or magnetic fields, also contain solid or liquid particles with sizes ranging from a few nanometers to a few micrometers. These media can be found in many natural environments as well as in various laboratory setups and industrial applications. As a separate branch of plasma physics, the field of dusty plasma physics was born in the beginning of 1990s at the intersection of the interests of the communities investigating astrophysical and technological plasmas. An additional boost to the development of the field was given by the discovery of plasma crystals leading to a series of microgravity experiments of which the purpose was to investigate generic phenomena in condensed matter physics using strongly coupled complex (dusty) plasmas as model systems. Finally, the field has gained an increasing amount of attention due to its inevitable connection to the development of novel applications ranging from the synthesis of functional nanoparticles to nuclear fusion and from particle sensing and diagnostics to nano-contamination control. The purpose of the present perspectives paper is to identify promising new developments and research directions for the field. As such, dusty plasmas are considered in their entire variety: from classical low-pressure noble-gas dusty discharges to atmospheric pressure plasmas with aerosols and from rarefied astrophysical plasmas to dense plasmas in nuclear fusion devices. Both fundamental and application aspects are covered. [ABSTRACT FROM AUTHOR]

The exosphere of Mercury, which has much in common with the exosphere of the Moon, can also contain suspended dust particles, which, under the action of intense solar radiation, acquire positive charges and form one of the components of the dusty plasma system. In addition to dust particles, there are photoelectrons above the planet surface, formed as a result of interaction of solar radiation with the planet surface, as well as with suspended dust particles. Mercury, unlike the Moon, has its own magnetosphere, which affects the parameters of dusty plasma system. The dusty plasma parameters near the Mercury surface can vary depending on the distance from the planet to the Sun, which considerably changes when the planet moves along the elongated orbit, and also depending on the localization of the region under consideration on the planet surface. Thus, near the magnetic poles, the solar wind can reach the planet surface, which must be taken into account when determining the plasma parameters. Far from the magnetic poles, the effect of the solar wind can be neglected. In the dusty plasma near the surface of Mercury, one can expect the development of linear and nonlinear wave processes. In this paper, nonlinear waves are considered, namely, dust acoustic solitons and nonlinear periodic waves. The profiles of potentials of high-amplitude solitons and nonlinear periodic waves are obtained, as well as the soliton amplitudes as functions of the altitude above the planet surface and soliton velocity. [ABSTRACT FROM AUTHOR]

When the hypersonic vehicle is flying, the plasma in the area near the stagnation point of the front end of the vehicle can be approximately seen as the fully ionized dusty plasma. Due to the existence of dust particles, dusty plasma affects the communication quality of the hypersonic vehicle. In this paper, the general Boltzmann equation applicable to dusty plasmas containing electrons and the Fokker–Planck–Landau collision model are combined to derive a general formula for the electron distribution function of fully ionized dusty plasmas. Considering the contribution of the collision effect and charging effect to the dispersion relationship of fully ionized dusty plasma, the dielectric constant of fully ionized dusty plasma under an external magnetic field is solved. The Wentzel–Kramers–Brillouin method is used to calculate the attenuation coefficient (α) of the THz wave in fully ionized dusty plasma, and the influence of the external magnetic field strength and other dusty plasma parameters on the attenuation characteristics of the THz circularly polarized wave is analyzed. The research results show that the α of the THz left-hand circularly polarized wave decreases with the increase in the external magnetic field strength, while the α of the THz right-hand circularly polarized wave increases. In addition, increasing the dust particle radius, dust particle density, and electron density in a certain frequency range can increase the α of the THz circularly polarized waves. These research results provide theoretical guidance for the exploration of the interaction mechanism between the THz waves and fully ionized dusty plasma. [ABSTRACT FROM AUTHOR]

In this paper, a (2+1)-dimensional Kadomtsev–Petviashvili (KP) equation is studied from the governing equations of dusty plasma by means of multiscale analysis and reduced perturbation method. We utilize the generalized exponential rational function method to give various forms of analytical solutions with free parameters of the corresponding equation by using Mathematica software calculation. Then, appropriate parameter values are selected to draw the three-dimensional (3D) diagram and contour diagram of the analytic solutions. We also give the influence of these physical parameters on wave amplitude, waves profile, and stability of waves. The results show the generalized method is a reliable mathematical method to solve similar nonlinear equations in mathematical physics and these solutions can enrich the physical behavior of the equation in dusty plasma. [ABSTRACT FROM AUTHOR]

In this paper, the cylindrical shock wave propagation in a perfectly conducting rotating mixture of micro size dust particles and van der Waal gas with magnetic field either axial or azimuthal and monochromatic radiation is investigated. The effect of thermal radiation is included in the energy equation of the governing system. In our study, it is assumed that the flux of radiation moves in the mixture of particles and real gas with invariable intensity and the shock wave is moving appositive to the direction of radiation heat flux and the energy is engrossed behind the cylindrical shock only. In the present model, dusty gas is assumed to be a mixture of micro size dust particles and van der Waal gas in which solid particles are continuously distributed and the equilibrium flow conditions are assumed to hold in the entire flow-field region. The effects of the particles' density to the initial gas density ratio, the real gas effect, rotational parameter, the concentration of mass of the micro size dust particles in the conducting mixture, Alfven-Mach number and the adiabatic exponent on shock and on the physical variables such as velocity, density etc. are discussed. It is found that due to the rotating medium consideration or by an increase in small particles density to the initial gas density ratio, the shock wave strength increases. Also, it is significant to memorize that the strength of the shock wave decreases by an increase in the strength of initial magnetic field or gas non-ideal parameter or the adiabatic index. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to extend the recent work of Paul and Bandyopadhyay [Astrophys. Space Sci. 361, 172 (2016)] on the existence of different dust ion acoustic solitary structures in an unmagnetized collisionless dusty plasma consisting of negatively charged static dust grains, adiabatic warm ions, nonthermal electrons, and isothermal positrons in a more generalized form by considering nonthermal positrons instead of isothermal positrons. The present system supports both positive and negative potential double layers, coexistence of solitary waves of both polarities, and positive potential supersolitons. The qualitative and quantitative changes in existence domains of different solitary structures, which occur in the presence of nonthermal positrons, have been presented in comparison with the results of Paul and Bandyopadhyay [Astrophys. Space Sci. 361, 172 (2016)]. The formation of supersoliton structures and their limitations has been analyzed with the help of phase portraits of the dynamical system corresponding to the dust ion acoustic solitary structures. Phase portrait analysis clearly indicates a smooth transition between solitons and supersolitons. [ABSTRACT FROM AUTHOR]

This paper presents the results of experimental and numerical investigation of the influence of dust nanoparticles on glow discharge plasma properties. A special apparatus was developed to provide a steady input of dust nanoparticles into ac glow discharge plasma. The plasma was created in a large-volume coaxial gridded hollow cathode. A novel simulation approach of dusty plasma was developed specifically for the experimental conditions. An extended fluid approach with drift-diffusion approximation for the electron and ion fluxes was modified to account for charged dust nanoparticles’ contribution to net charge and for ion and electron loss on the surface of particles. Uniform distribution of dust particles in plasma and instantaneous charging process were assumed during simulations. Experimental measurements were carried out using Langmuir probe. Simulations and probe measurements were carried out before and after input of dust particles into plasma. Under the conditions studied both methods showed a decrease by a factor of 5 in electron density caused by input of dust nanoparticles. [ABSTRACT FROM AUTHOR]

Dusty plasma diffusion was applied to model the plasma response to perturbations in dust density, which yields small‐scale irregularities in electron density that are responsible for Polar Mesosphere Summer Echos. Previous diffusion models treated aerosols either as fixed‐charge dust or as multiple‐charge‐state dust using chemical rate equations. The growth of aerosol particles was previously considered in the study of layered structures in mesospheric clouds, but it has not been incorporated into dust diffusion. In this paper, a multicomponent diffusion of a dusty plasma, consisting of electrons, ions, and charged aerosols, is developed, accounting for the growth of the aerosols. It is shown that, for typical parameters in polar mesopause region, the evolution of the density structures of the dusty plasma undergoes an initial charging process (approximately 100 s), then an ambipolar diffusion process on ion time scale (approximately hundreds of seconds), and the aerosol diffusion on dust time scale (>104 s). Furthermore, the growth of the aerosols retards the dust diffusion and causes the transition from anticorrelation to correlation between the electron and ion density perturbations (contrary to only anticorrelation or correlation as in the case without considering the growth). The growth also bends the density profiles from upward shifting to downward sedimentation. In addition, larger initial grain radius and the width of the initial perturbation result in slower diffusion. The diffusion is much faster at 88 km than at 82 km. Key Points: Multicomponent diffusion model including the growth of dust grains was established and numerically studiedDust growth retards the diffusion and causes the transition from anticorrelation to correlation between electron and ion densitiesDust growth bends density profiles from upward shifting to downward sedimentation on a time scale of a few thousand seconds [ABSTRACT FROM AUTHOR]

In this paper, the problem of large amplitude dust acoustic (DA) solitons has been addressed in a charge varying dusty plasma with ions following a Cairns‐Gurevich distribution. Based on the orbit motion limited approach, the correct Cairns‐Gurevich ion charging current is presented for the first time. The expression relating the variable dust charge to the plasma potential is given in terms of the Lambert function and we take advantage of this transcendental function to, carefully, analyse DA solitons in a charge varying dusty plasma with trapped nonthermal ions. Our results show that the spatial patterns of the variable charge solitary wave are significantly changed due to the presence of ion population modelled by the Cairns‐Gurevich distribution. An addition of a small concentration of trapped nonthermal ions makes the solitary structure less spiky, grows the net negative charge residing on the dust grain surface, and contributes to the electron depletion. Finally, our investigation is extended to highlight the effect of the grain dust charge variation. We have shown that under certain conditions, the impact of dust charge fluctuation may furnish an alternate physical mechanism rasing anomalous dissipation, which becomes more strong and may predominate over the dispersion as the nonthermal character of ions following the Cairns‐Gurevich distribution increases. [ABSTRACT FROM AUTHOR]