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This paper presents a novel viewpoint on nonlinear dust-acoustic waves (DAWs) in an unmagnetized collisionless plasma containing regularized κ distributed electrons and ions (ei) and negative dust grain. The nonlinear oscillatory system based on hybridization of the Van der Pol–Mathieu equation (VdPME) is derived by a new technique. By bifurcation analysis of the planar dynamical system (DS), the effects of parameters with the assistance of phase planes and time series of VdPME are studied. After analyzing the equation to identify the resonance region, a fourth-order Runge–Kutta method is used to solve it numerically. We explained the behavior of DA periodic, stable limit cycle, and chaotic limit cycle wave solutions with different parameters. These types of numerical solutions are illustrated in two-dimensional and three-dimensional graphics by changing the rate at which charged dust grain is produced α, as well as waste β and comparing the results with those of earlier research. A novel bifurcation analysis of VdPE and VdPME is obtained with the effects of the cut-off factor δ of regularized κ-distribution (RKD) distributed ei, the superthermality of ei particles κe,i, the ratio of ion to electron temperature σ, and the ratio of dust to electron density ρ illustrated.  It is noticed that the DAW shows promotion in width and amplitude as the frequency γ increases and it becomes rarefaction as the cut-off parameter δ increases. On the contrary, it becomes compressive under the impact of superthermality κe and κi. The obtained conclusions may help explain and comprehend a variety of applications in experimental plasma containing highly energy regularized κ dispersed ei, as well as in the interstellar medium. [ABSTRACT FROM AUTHOR]

In this paper, the role of dust grain's gravitational force on the nonlinear dust‐acoustic oscillations in non‐Maxwellian dusty plasma is analyzed. It is shown that increasing the number of non‐thermal ions causes the diminution of the electrostatic potential's amplitude and a reduction in the number of oscillations introduced by the gravitational force. We have also found that reducing the size of the dust grain induces qualitatively the same effects as an increase in the number of non‐thermal ions and when the gravitational force is considered, the electric charge exhibits oscillatory profile and becomes less negative far away from the origin. This result may be interesting in the study of astrophysical plasmas where the electromagnetic force is smaller than the gravitational one such as in the Halley Comet. [ABSTRACT FROM AUTHOR]

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]

This paper investigates the influence of compressibility on the internal wave modes and the density gradient-driven Rayleigh–Taylor (R–T) instability in magnetized strongly coupled dusty plasmas. The dusty magnetohydrodynamic model is formulated for compressible fluids, accounting for the effects of weakly coupled electrons/ions and strongly coupled dust particles under the influence of the gravitational field. The effect of the magnetic field on the dust dynamics has been incorporated through the magnetic force on the electrons and ions in quasineutral dusty plasmas. A dispersion relation of the R–T instability has been derived which has been modified because of the compressibility effect, dust acoustic wave speed and viscoelastic coefficients. The shear Alfvén and compressional viscoelastic wave modes become coupled in the dispersion characteristics. The modified R–T instability criterion is derived in terms of the Alfvén speed, viscoelastic effects and dust grain parameters. The graphical illustrations show that the growth rate of R–T instability has been suppressed due to compressibility, viscoelastic coefficients and dust acoustic speed. The results are useful to discuss the development of R–T instability in magnetized astrophysical dusty plasmas. [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]

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]

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 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]

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]

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]

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]

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 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]

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]

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]

Intermediate-luminosity red transients (ILRTs) are a class of observed transient posited to arise from the production of an electron-capture supernova from a super-asymptotic giant branch star within a dusty cocoon. In this paper, we present a systematic analysis of narrow Na  i D absorption as a means of probing the circumstellar environment of these events. We find a wide diversity of evolution in ILRTs in terms of line strength, time-scale, and shape. We present a simple toy model designed to predict this evolution as arising from ejecta from a central supernova passing through a circumstellar environment wherein Na  ii is recombining to Na  i over time. We find that while our toy model can qualitatively explain the evolution of a number of ILRTs, the majority of our sample undergoes evolution more complex than predicted. The success of using the Na  i D doublet as a diagnostic tool for studying circumstellar material will rely on the availability of regular high-resolution spectral observations of multiple ILRTs, and more detailed spectral modelling will be required to produce models capable of explaining the diverse range of behaviours exhibited by ILRTs. In addition, the strength of the Na  i D absorption feature has been used as a means of estimating the extinction of sources, and we suggest that the variability visible in ILRTs would prevent such methods from being used for this class of transient, and any others showing evidence of variability. [ABSTRACT FROM AUTHOR]

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]

In this paper, the effect of iron oxide nanoparticles dust (Fe2O3 NPs) on the parameters of DC electric discharge plasma under vacuum in argon gas was studied with the presence of a mirror magnetron behind the electrodes (cathode and anode) at constant pressure and with different amounts of Fe2O3 nanoparticles. Calculations presented a reduction of the plasma emission intensity with the NPs content. Both the plasma density (calculated by Stark's broadening method) and the mean electron temperature (calculated using Boltzmann's equation) decreased with increasing the Fe2O3 nanoparticles dust content, which indicates clearly the effect of dust density on restricting the movement of charge carriers, which in turn reduces inelastic plasma collisions. [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, 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]

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]

This paper presents fully-kinetic numerical investigations of the charging of spherical and irregular dust grains in the OML sheath regime and a stationary experimental plasma environment utilizing the Dusty Parallel Immersed-Finite-Element Particle-in-Cell (PIFE-PIC-D) framework. The simulations account for surface charging of the dust grains immersed in an stationary plasma environment. PIFE-PIC-D explicitly resolves the geometrical and material properties (permittivity) of each individual dust grain. The charge collection over time of each dust grain is investigated with varying size, irregularity, number of grains, spacing between dust grains, and permittivity. The charging behavior of a dust cluster is estimated by calculating its electron Debye length edge-to-edge separation to offer valuable insights into a dust cluster's general charge dynamics. Lastly, unlike prior studies that focused solely on either fully conducting spheres or perfectly dielectric spheres, this work explores a more comprehensive range of permittivities for irregular dust grain aggregates. • Dielectric spherical and irregular dust grain (varying permittivity) charging. • Fully-kinetic numerical simulations resolving the charging process. • Confirming the net charge ratio, Q_d/e, on the order of approximately 10̂4, for the corresponding experimental plasma environment, and investigating the charging behavior with respect to Debye length spacing among dust grains. [ABSTRACT FROM AUTHOR]

Motivated by observations of localized electrostatic wavepackets by the Voyager 1 and 2 and Cassini missions in Saturn's magnetosphere, we have investigated the evolution of modulated electrostatic wavepackets in a dusty plasma environment. The well-known dust-ion acoustic (DIA) mode was selected to explore the dynamics of multidimensional structures, by means of a Davey–Stewartson (DS) model, by taking into account the presence of a highly energetic (suprathermal, kappa-distributed) electron population in combination with heavy (immobile) dust in the background. The modulational (in)stability profile of DIA wavepackets for both negative as well as positive dust charge is investigated. A set of explicit criteria for modulational instability (MI) to occur is obtained. Wavepacket modulation properties in 3D dusty plasmas are shown to differ from e.g. Maxwellian plasmas in 1D. Stronger negative dust concentration results in a narrower instability window in the K (perturbation wavenumber) domain and to a suppressed growth rate. In the opposite manner, the instability growth rate increases for higher positive dust concentration and the instability window gets larger. In a nutshell, negative dust seems to suppress instability while positive dust appears to favour the amplitude modulation instability mechanism. Finally, stronger deviation from the Maxwell–Boltzmann equilibrium, i.e. smaller κ e values, lead(s) to stronger instability growth in a wider wavenumber window – hence suprathermal electrons favour MI regardless of the dust charge sign (i.e. for either positive or negative dust). The wavepacket modulation properties in 2D dusty plasmas thus differ from e.g. Maxwellian plasmas in 1D, both quantitatively and qualitatively, as indicated by a generalized dispersion relation explicitly derived in this paper (for the amplitude perturbation). Our results can be compared against existing experimental data in space, especially in Saturn's magnetosphere. [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]

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]

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]

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]

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]

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]

Kelvin–Helmholtz (KH) instability plays a significant role in transport and mixing in various media such as hydrodynamic fluids, plasmas, geophysical flows and astrophysical situations. In this paper, we numerically explore this instability for a two-dimensional strongly coupled dusty plasma medium with rotational shear flows. We study this medium using a generalized hydrodynamic fluid model which treats it as a viscoelastic fluid. We consider the specific cases of rotating vorticity with abrupt radial profiles of rotation. In particular, single-circulation and multi-circulation vorticity shell profiles have been chosen. We observe the KH vortices at each circular interface between two relative rotating flows along with a pair of ingoing and outgoing wavefronts of transverse shear waves. Our studies show that due to the interplay between KH vortices and shear waves in the strongly coupled medium, the mixing and transport behaviour are much better than those of standard inviscid hydrodynamic fluids. In the interest of substantiating the mixing and transport behaviour, the generalized hydrodynamic fluid model is extended to include Lagrangian tracer particles. The numerical dispersion of these tracer particles in a flow provides an estimate of the diffusion in such a medium. We present the preliminary observations of tracer distribution (cluster formation) and diffusion (mean square displacement) across the medium. [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]

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]

In this paper, a numerical examination of propagating nonlinear dissipative dust-acoustic breathers and rogue waves (RWs) in electron depleted dusty plasmas having two superthermal ions of different temperature has been made. An important ingredient in this study is the inclusion of the dissipative effect due to the viscosity of the dust grains in the evolution wave equation. Accordingly, a damped/modified nonlinear Schrödinger equation (DNLSE), i.e. the standard nonlinear Schrödinger equation (NLSE) in addition to the damping term, is obtained using a reductive perturbation (the derivative expansion) method. Without taking into account the effect of dust viscosity, the standard NLSE is also examined, and the effect of relevant physical parameters on the breathers and rogue waves is examined. Moreover, the impact of dust kinetic viscosity on both breather structures and RWs is investigated by solving DNLSE numerically with the Dirichlet boundary conditions. This model may be useful to understand the excitation of dust-acoustic waves in the Earth's magnetotail. [ABSTRACT FROM AUTHOR]

In this paper, we give a detailed description of a novel plasma chamber—the Zyflex chamber—that has been specifically designed for complex/dusty plasma research under reduced gravitational influence as realized during parabolic flight or aboard the International Space Station. The cylindrical, radio-frequency driven discharge device includes a variety of innovations that, for example, allow us to flexibly adjust plasma parameters and its volume via enhanced plasma generation control and a movable, multi-segmented electrode system. The new complex/dusty plasma research tool also supports, due to its overall increased size compared to former space based complex plasma experiments such as PKE-Nefedov or PK-3 Plus, much larger particle systems. Additionally, it can be operated at much lower neutral gas pressures, thus reducing the damping of particle motion considerably. Beyond the technical description and particle-in-cell simulation based characterization of the plasma vessel, we show sample results from experiments performed with this device in the laboratory as well as during parabolic flights, both of which clearly demonstrate the new quality of complex/dusty plasma research that becomes accessible with this new plasma device. [ABSTRACT FROM AUTHOR]

Present paper studies the contribution of both the quantum effect and the dust size distribution effect on the shock wave characters. It is concluded that the quantum effect of dust particles is negligible, while the quantum effects of both electrons and ions on the shock wave of a quantum dusty plasma cannot be neglected in certain cases. It is found that the speed and the amplitude of the shock wave, considering the dust size distribution, are larger than that of the quantum dusty plasma with the average dust size of a monosized dust plasma. Furthermore, the speed and the amplitude of the shock wave increase, while the width of the shock wave decreases as the ratios of the maximum dust size to the minimum one increases. The quantum effects may affect both the amplitude and width of the shock wave, while it has no effect on the shock wave speed. The width of the shock wave increases, while its amplitude decreases as H e and H i increase. [ABSTRACT FROM AUTHOR]

Plasma is an ionized gas that responses collectively to any external (or internal) perturbation. Introducing micron-sized solid dust particles into plasma makes it more interesting. The dust particles acquire large negative charges on their surface in low-temperature laboratory plasma and exhibit collective behavior similar to the ambient plasma medium. Some remarkable features of the charged dust grain medium (dusty plasma) allow us to use it as a model system to understand a number of physics phenomena at a microscopic level. In this perspective paper, the author highlights the role of dusty plasma experiments as a learning tool for undergraduate and post-graduate physics students at higher academic institutions. Students could have great opportunities to understand basic physical phenomena as well as learn about many advanced data analysis tools and techniques by performing dusty plasma (plasma) experiments. A few simple experiments in a single dusty plasma device that connect the basic physics phenomena are discussed. [ABSTRACT FROM AUTHOR]

The creation of a spatially extended stable DC complex plasma crystal is a big experimental challenge and a topical area of research in the field of dusty plasmas. In this paper we describe a newly built and commissioned dusty plasma experimental (DPEx-II) device at the Institute for Plasma Research. The device can support the formation of large sized Coulomb crystals in a DC glow discharge plasma. The plasma in this L-shaped table-top glass chamber is produced between a circular anode and a long tray shaped cathode. It is characterized with the help of various electrostatic probes over a range of discharge conditions. The dust particles are introduced by a dust dispenser to form a strongly coupled Coulomb crystal in the cathode sheath region. The unique asymmetric electrode configuration minimizes the heating of dust particles and facilitates the formation of crystalline structures with a maximum achievable dimension of 40 cm × 15 cm using this device. A larger crystal has numerous advantages over smaller ones, such as higher structural homogeneity, fewer defects, lower statistical errors due to finite size effects etc. A host of diagnostics tools are provided to characterize the Coulomb crystal. Results of a few initial experiments aimed at demonstrating the technical capabilities of the device and its potential for future dusty plasma research, are reported. [ABSTRACT FROM AUTHOR]

Dust particles generated from the thermal protection layer greatly influence the propagation of electromagnetic (EM) waves in the plasma sheath. This paper presents the first calculation of the effects of these dust particles on microstrip antenna radiation. On the basis of an integrated model of the ablation plasma sheath and C-band microstrip antenna, the ray tracing method is used to obtain the disturbed electric field in a traditional plasma and a dusty plasma (with different dust parameters). The results show that the dust particles cause greater attenuation of incident waves, and different dust parameters have different effects on the penetrating electric field. This study reveals that the ablation of the thermal protection layer changes the electromagnetic properties of the plasma sheath, and the generated dust particles should not be ignored in the electromagnetic computation. [ABSTRACT FROM AUTHOR]

This paper presents recent progress on the development of the new multi-purpose particle modeling and simulation tool VizGrain. A unique aspect of VizGrain is that it allows computational modeling of particle dynamics in a variety of systems, including rarefied gas dynamics, macroscopic particle dynamics (e.g., dust particles, droplets, etc), particle-in-cell modeling, and hybrid continuum-particle modeling within a single integrated framework. VizGrain allows working with atomic sized particles and particles with finite macroscopic sizes. The former approach is used to model rarefied gas dynamics and conventional non-equilibrium plasmas, while the finite sized macro-particles are considered for the modeling of dusty plasmas, aerosols, droplets etc. In this latter case, the electrical charge up of particles in a plasma environment is considered. The model features a comprehensive variety of drag forces that can act on both atomic and macro-particles. A detailed description of the physical models implemented within VizGrain is presented, to provide insights into the approach that can be taken in other particle-based codes in the community. These models are scrupulously validated against the benchmark problems proposed in the research literature for a variety of applications from the plasma reactors used in semiconductor industry to high-speed rarefied gas dynamics problems. [ABSTRACT FROM AUTHOR]

In this paper, we investigate dust acoustic solitary waves in dusty inhomogeneous plasma with a weak density gradient. For this, Lie analysis is utilized and solitary waves are obtained with the aid of the newly extended direct algebraic method. The solutions so obtained carry a variety of some new families including dark-bright, dark, dark-singular, and singular solutions of types 1 and 2. The sufficient conditions for the existence of these structures are given. Meantime, the effect of parameters like dust charge, cold ion density, and number density on the soliton structures are investigated in detail, which shows that dust charge affects the amplitude but density does not put any impact on soliton's profile. A graphical approach is practiced to discuss the physical impact of the problem. Finally, by using a multiplier approach, conserved quantities are reported. [ABSTRACT FROM AUTHOR]

In this paper, the formation of the electron energy distribution function (EEDF) in the argon dusty plasma of the positive column of glow discharge at low pressure is investigated. A model for calculating EEDF in the local approximation is adapted to find the nonlocal EEDF via the Holstein–Tsendin model. The results show that, contrary to the prevalent opinion in the literature, the presence of dust has little effect on the EEDF up to the limiting values of the density of dust particles that can be injected into the plasma for the considered conditions. It is also shown that, when obtaining the nonlocal EEDF, the spatial profiles of the axial (heating) and radial (ambipolar) fields should be chosen from a self-consistent solution. Additionally, the differences between the local and nonlocal EEDFs increase in the peripheral regions of the discharge due to a sharp decrease of fast electrons in the nonlocal case. Significant changes in the form of the nonlocal EEDF along the radius also lead to noticeable changes in other characteristics of the electrons in this area, especially for those with a large energy threshold (e.g. due to excitation, ionization). [ABSTRACT FROM AUTHOR]

In the presence of the substrate, various structural and dynamical properties of two-dimensional dusty plasma (2DDP) were investigated using Langevin dynamical simulations. This paper reviews a series of results of the structural and dynamical properties of 2DDP modified by one-dimensional periodic substrates (1DPSs) as follows. First, when the depth of the 1DPS increases gradually, it is found that the static structural order of 2DDP along each potential well of the 1DPS increases first and then decreases gradually. When the width of the 1DPS increases gradually, the particle arrangement in each potential well of the 1DPS changes from one straight row gradually to two rows, including the stable zigzag structure. Second, when there are two rows in each potential well of the 1DPS, the phonon spectra are split into two branches, corresponding to the breathing and sloshing modes, respectively. In addition, due to the pure repulsion between dust particles, from the obtained phonon spectra, the sloshing wave propagates backward at small wave numbers. Third, the calculated mean square displacement shown that, at the intermediate timescale between the initial ballistic and final diffusive motions, the particle motion tends to be more subdiffusive while the depth of the 1DPS increases. While the width of the 1DPS increases gradually, the long-time diffusive motion first increases, then decreases, and finally increases again, exhibiting the oscillation-like diffusion, due to the stable zigzag structure. Finally, when an external direct-current driving force is applied on all particles of 2DDP, three different depinning phases are discovered, which are the pinned, disordered plastic flow, and moving ordered states, respectively, as the driving force increases from zero. In addition, the continuous/discontinuous property of the phase transition between these different depinning states is investigated, showing that the transition property is modulated by the depth of the applied 1DPS. [ABSTRACT FROM AUTHOR]

Both the linear and the nonlinear magnetosonic wave in a multi-component dusty plasma are studied in the present paper. The dependence of the dispersion relation of the linear waves on the dust size distribution are given. It seems that the larger the difference between the maximum and the minimum radius of the dust grains, the lower the wave frequency for all cases of the dust size distribution. Furthermore, it is noted that the width, the amplitude and the propagation velocity of the KdV solitary wave depend on the dust size distribution, especially it depend on whether the number density of the larger sized dust grain is larger or smaller than that of the smaller sized dust grain. For the power law dust size distribution, the width and the propagation velocity of the KdV solitary wave between the maximum and the minimum radius of the dust grains is larger than that of mono-sized dusty plasma. [ABSTRACT FROM AUTHOR]

The Bitter Electromagnet Testing Apparatus (BETA) is a 1-Tesla (T) technical prototype of the 10 T Adjustable Long Pulsed High-Field Apparatus. BETA’s final design specifications are highlighted in this paper which include electromagnetic, thermal, and stress analyses. We discuss here the design and fabrication of BETA’s core, vessel, cooling, and electrical subsystems. The electrical system of BETA is composed of a scalable solid-state DC breaker circuit. Experimental results display the stable operation of BETA at 1 T. These results are compared to both analytical design and finite element calculations. Experimental results validate analytical magnet designing methods developed at the Dusty Plasma Laboratory. The theoretical steady state maxima and the limits of BETA’s design are explored in this paper. [ABSTRACT FROM AUTHOR]

Purpose The purpose of this paper is to provide an analysis of dust acoustic (solitary) waves including viscosity. Specifically, the authors consider a dusty unmagnetized plasma system consisting of negatively charged dust and Boltzmann electrons and ions.Design/methodology/approach In this paper, a Petrov–Galerkin weak form with upwinding is adopted. Nonlinearity of ion and electron number density in terms of an electrostatic potential is included. A fully implicit time integration is used (backward Euler method), which requires the first derivative of the weak form. A three-field formulation is proposed, with the dust number density, the electrostatic potential and the dust velocity being the unknown fields.Findings In this study, two numerical examples are introduced and results show great promise for the proposed formulation as a predictive tool in viscous dusty plasmas. Presence of solitary waves was demonstrated. Dusty plasma vortices are predicted in 2D and 3D, as mentioned in the specialized literature.Research limitations/implications We observed some dependence on step size, which is due to the simple time-stepping scheme. This can be solved with a higher order integration scheme, which implies an added cost to the solution.Practical implications Dusty plasmas are found in astrophysics (Saturn rings) and electronics industry at several scales and have high impact as a contaminant.Originality/value To the authors’ knowledge, this is the first paper with a simulation of dusty plasma including vortices. [ABSTRACT FROM AUTHOR]