Latest in physics.plasm-ph

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Particle-In-Cell simulations of the proton firehose instability influenced by the electron temperature anisotropy in solar wind conditionsJul 19 2019The expansion of the solar wind plasma generates anisotropic particle distributions, so that the temperature in the direction parallel to the interplanetary magnetic field becomes higher than the temperature in the perpendicular direction. This configuration ... More
Impact of main ion pressure anisotropy on stellarator impurity transportJul 19 2019Main ions influence impurity dynamics through a variety of mechanisms; in particular, via impurity-ion collisions. To lowest order in an expansion in the main ion mass over the impurity mass, the impurity-ion collision operator only depends on the component ... More
Cross-field chaotic transport of electrons by $\vec E \times \vec B$ electron drift instability in Hall thrustersJul 19 2019One special interest for the industrial development of Hall thruster is characterizing the anomalous cross-field electron transport observed after the channel exit. Since the ionization efficiency is more than 90%, the neutral atom density in that domain ... More
Physics of relativistic collisionless shocks: II Dynamics of the background plasmaJul 18 2019In this second paper of a series, we discuss the dynamics of a plasma entering the precursor of an unmagnetized, relativistic collisionless pair shock. We discuss how this background plasma is decelerated and heated through its interaction with a microturbulence ... More
Formation of quasi-periodic slow magnetoacoustic wave trains by the heating/cooling misbalanceJul 18 2019Slow magnetoacoustic waves are omnipresent in both natural and laboratory plasma systems. The wave-induced misbalance between plasma cooling and heating processes causes the amplification or attenuation, and also dispersion, of slow magnetoacoustic waves. ... More
Magnetic reconnection with null and X-pointsJul 18 2019Null and X-points of magnetic fields are places at which magnetic field lines with fundamentally different topologies approach each other arbitrary closely before separating by a distance set by the overall size of the configurtion. Even in a collision-free ... More
New ion energy-mass spectrometer ULTIMAN (UlTImate Mass ANalyzer) for space plasmasJul 18 2019Measurements of Ion velocity distributions are one of basic goals of space plasma studies. There is variety of ion and electron spectrometers (e.g. Wuest et al, 2007, Young et al., 2007, Zurbuchen and Gershman, 2016, Vaisberg et al, 2016). The most frequently ... More
Dust-acoustic rogue waves in an electron depleted plasmaJul 18 2019A rigorous theoretical investigation is made to study the characteristics of dust-acoustic (DA) waves (DAWs) in an electron depleted unmagnetized opposite polarity dusty plasma system that contains super-thermal ($\kappa$-distributed) ions, mobile positively ... More
Physics of relativistic collisionless shocks: The scattering center frameJul 17 2019In this first paper of a series dedicated to the microphysics of unmagnetized, relativistic collisionless pair shocks, we discuss the physics of the Weibel-type transverse current filamentation instability (CFI) that develops in the shock precursor, through ... More
Plasma-MDS -- A metadata schema for applied plasma science and plasma medicineJul 17 2019A metadata schema, named Plasma-MDS, is introduced to support research data management in applied plasma science and plasma medicine. Plasma-MDS is suitable to facilitate the publication of research data following FAIR principles in domain-specific repositories ... More
The physics of Weibel-mediated relativistic collisionless shocksJul 17 2019We develop a comprehensive theoretical model of relativistic collisionless pair shocks mediated by the current filamentation instability. We notably characterize the noninertial frame in which this instability is of a mostly magnetic nature, and describe ... More
Large-Scale Parallel Electric Fields and Return Currents in a Global Simulation ModelJul 17 2019A new computational model, kglobal, is being developed to explore energetic electron production via magnetic reconnection in macroscale systems. The model is based on the discovery that the production of energetic electrons during reconnection is controlled ... More
A filtered Boris algorithm for charged-particle dynamics in a strong magnetic fieldJul 17 2019A modification of the standard Boris algorithm, called filtered Boris algorithm, is proposed for the numerical integration of the equations of motion of charged particles in a strong non-uniform magnetic field in the asymptotic scaling known as maximal ... More
General relativistic resistive magnetohydrodynamics with robust primitive variable recovery for accretion disk simulationsJul 16 2019Recent advances in black hole astrophysics, particularly the first visual evidence of a supermassive black hole at the center of the galaxy M87 by the Event Horizon Telescope (EHT), and the detection of an orbiting "hot spot" nearby the event horizon ... More
In-situ observation of Hall Magnetohydrodynamic Cascade in Space PlasmaJul 16 2019We present estimates of the turbulent energy cascade rate, derived from a Hall-MHD third-order law. We compute the contribution from the Hall term and the MHD term to the energy flux. We use MMS data accumulated in the magnetosheath and the solar wind, ... More
Depinning dynamics of two-dimensional dusty plasmas on a one-dimensional periodic substrateJul 15 2019We investigate the depinning dynamics of two-dimensional dusty plasmas (2DDP) driven over one-dimensional periodic substrates (1DPS) using Langevin dynamical simulations. We find that, for a specific range of substrate strengths, as the external driving ... More
Optimal Control of a Hot PlasmaJul 15 2019The time evolution of a collisionless plasma is modeled by the relativistic Vlasov-Maxwell system which couples the Vlasov equation (the transport equation) with the Maxwell equations of electrodynamics. We consider the case that the plasma is located ... More
Electron dynamics in counter-propagating laser wavesJul 12 2019The electron dynamics in counter-propagating laser waves is investigated by employing a novel approach, where the new Hamiltonian is time-independent when the perturbative laser wave is absent. The physical picture of stochastic electron dynamics is clearly ... More
Analysis of azimuthal magnetorotational instability and Tayler instability of rotating MHD flows via an extended Hain-Lust equationJul 11 2019Short-wavelength local analysis and numerical global analysis are made of the azimuthal magnetorotational instability of rotating flows of an electrically conducting fluid, subject to an arbitrary but axisymmetric azimuthal magnetic field, to three-dimensional ... More
A novel, compact and portable 2-LTD-Brick x-pinch radiation source: its development and radiation performanceJul 11 2019Almost all well-known x-pinch x-ray radiation machines are large, based on a conventional Marx generator, and lack portability. The literature suggests that a current rate of rise of 1 kA/ns or more is required for "good" x-pinch radiation performance, ... More
Optical conductivity in graphene: hydrodynamic regimeJul 11 2019Experimental investigation of hydrodynamics in electron fluids is a highly topical research area that emerged during the last few years. A recent measurement of the optical conductivity in graphene [P. Gallagher et.al, Science 364, 158 (2019)] offers ... More
A new compact, portable 2-LTD-brick x-pinch driver at the Idaho Accelerator Center: design, fabrication, testing and x-ray performanceJul 11 2019We propose to construct a compact and portable x-pinch driver with x-ray radiation performance, comparable to standard x-pinch drivers. Such a new x-pinch driver was recently designed, fabricated and tested at the Idaho Accelerator Center. The generator ... More
Theory of Edge Localized Mode Suppression by Static Resonant Magnetic Perturbations in the DIII-D TokamakJul 09 2019Recent research (Hu, et al. 2019) has shed considerable light on the poorly understood physical mechanism that underlies the suppression of edge localized modes (ELMs) by externally applied resonant magnetic perturbations (RMPs) in H-mode tokamak plasmas. ... More
An application of survival analysis to disruption prediction via Random ForestsJul 09 2019One of the most pressing challenges facing the fusion community is adequately mitigating or, even better, avoiding disruptions of tokamak plasmas. However, before this can be done, disruptions must first be predicted with sufficient warning time to actuate ... More
Seed and vacuum pair production in strong laser fieldJul 08 2019Researches on the electron-positron pair production in the presence of the intense laser field are reviewed, motivated by the theoretical importance of the nonperturbative QED problem and the worldwide development of the strong laser facilities. According ... More
Seed and vacuum pair production in strong laser fieldJul 08 2019Jul 11 2019Researches on the electron-positron pair production in the presence of the intense laser field are reviewed, motivated by the theoretical importance of the nonperturbative QED problem and the worldwide development of the strong laser facilities. According ... More
Evidence of non collisional femtosecond laser electron heating in dielectric materialsJul 08 2019Electron dynamics in the bulk of large band gap dielectric crystals induced by intense femtosecond laser pulses at 800 nm is studied. With laser intensities under the ablation threshold (a few 10 TW/cm\textsuperscript{2}), electrons with unexpected energies ... More
The Turbulent DynamoJul 08 2019The generation of magnetic field in an electrically conducting fluid generally involves the complicated nonlinear interaction of flow turbulence, rotation and field. This dynamo process is of great importance in geophysics, planetary science and astrophysics, ... More
Laser-driven generation of collimated quasi-monoenergetic proton beam using double-layer target with interface modulationsJul 08 2019Usage of double-layer targets consisting of heavy and light material with modulated interface between them provides a way for laser-driven generation of collimated ion beams. With extensive 2D3V PIC simulations we show that this configuration may result ... More
Instabilities and Turbulence in Low-$β$ Guide Field Reconnection Exhausts with Kinetic Riemann SimulationsJul 06 2019We have used a 2D reconnection simulation, 2D and 3D Riemann simulations, as well as a kinetic dispersion relation solver to explore the role of instabilities and turbulence in low-$\beta$, guide field reconnection exhausts. The 2D reconnection and Riemann ... More
The effect of hyperfine splitting on Stark broadening for three blue-green Cu I lines in laser-induced plasmaJul 05 2019Stark effect is observed in many natural and artificial plasmas and is of great importance for diagnostic purposes. Since this effect alters profiles of spectral lines, it should be taken into account when assessing chemical composition of radiation sources, ... More
High-Energy Radiation and Pair Production by Coulomb Processes in Particle-In-Cell SimulationsJul 05 2019We present a Monte Carlo implementation of the Bremsstrahlung, Bethe-Heitler and Coulomb Trident processes into the particle-in-cell (PIC) simulation framework. In order to address photon and electron-positron pair production in a wide range of physical ... More
Inference of $α$-particle density profiles from ITER collective Thomson scatteringJul 05 2019The primary purpose of the collective Thomson scattering (CTS) diagnostic at ITER is to measure the properties of fast-ion populations, in particular those of fusion-born $\alpha$-particles. Based on the present design of the diagnostic, we compute and ... More
Modelling the electron cyclotron emission below the fundamental resonance in ITERJul 05 2019The electron cyclotron emission (ECE) in fusion devices is non-trivial to model in detail at frequencies well below the fundamental resonance where the plasma is optically thin. However, doing so is important for evaluating the background for microwave ... More
Radiation induced acceleration of ionsJul 04 2019In a transparent target exposed to a strong laser pulse radiation friction can have a substantial impact on electron dynamics. In particular, by modifying quiver electron motion, it can strongly enhance the longitudinal charge separation field, thus stimulating ... More
Accurate single-shot measurement technique for the spectral distribution of GeV electron beams from a laser wakefield acceleratorJul 04 2019We present a technique, based on a dipole magnet spectrometer containing multiple scintillation screens, to accurately characterize the spectral distribution of a GeV electron beam generated by laser wakefield acceleration (LWFA). An optimization algorithm ... More
Current channel evolution in ideal Z pinch for general velocity profilesJul 03 2019Recent diagnostic advances in gas-puff Z pinches at the Weizmann Institute for the first time allow the reconstruction of the current flow as a function of time and radius. These experiments show an unexpected radially-outward motion of the current channel, ... More
Ion dominated mechanism for coupling laser energy to plasmaJul 03 2019The well-known schemes (e.g. Brunel, resonance, JxB heating etc.,) of laser energy absorption in plasma are mediated through the lighter electron species. In this work a fundamentally new mechanism of laser energy absorption directly through the heavier ... More
Three-Dimensional X-line Spreading in Asymmetric Magnetic ReconnectionJul 03 2019The spreading of the X-line out of the reconnection plane under a strong guide field is investigated using large-scale three-dimensional (3D) particle-in-cell (PIC) simulations in asymmetric magnetic reconnection. A simulation with a thick, ion-scale ... More
Properties of magnetohydrodynamic modes in compressively driven plasma turbulenceJul 03 2019We study properties of magnetohydrodynamic (MHD) eigenmodes by decomposing the data of MHD simulations into linear MHD modes - namely the Alfven, slow magnetosonic, and fast magnetosonic modes. We drive turbulence with a mixture of solenoidal and compressive ... More
RF current condensation in magnetic islands and associated hysteresis phenomenaJul 02 2019The nonlinear RF current condensation effect suggests that magnetic islands might be well controlled with broader deposition profiles than previously thought possible. To assess this possibility, a simplified energy deposition model in a symmetrised 1D ... More
Maximum-Entropy States for Magnetized Ion TransportJul 02 2019For a plasma with fixed total energy, number of particles, and momentum, the distribution function that maximizes entropy is a Boltzmann distribution. If, in addition, the rearrangement of charge is constrained, as happens on ion-ion collisional timescales ... More
Stellarators with permanent magnetsJul 02 2019It is shown that the magnetic-field coils of a stellarator can, at least in principle, be substantially simplified by the use of permanent magnets. Such magnets cannot create toroidal magnetic flux but they can be used to shape the plasma and thus to ... More
Comment on "Ion velocity analysis of rotating structures in a magnetic linear plasma device" [Phys. Plasmas 25, 061203 (2018)]Jul 02 2019In a recent paper (Phys. Plasmas 25, 061203, 2018), the authors have presented the analysis of the electric ion drift velocity experienced by heavy ions created in a plasma submitted to a low magnetic field. Unfortunately, they have used the classical ... More
Relativistic near-single-cycle optics at 1 kHzJul 02 2019We present a laser source delivering waveform-controlled 1.5-cycle pulses that can be focused to relativistic intensity at 1 kHz repetition rate. These pulses are generated by nonlinear compression of high-temporal-contrast sub-25\,fs pulses from a kHz ... More
A compact electron injector for the EIC based on plasma wakefields driven by the RHIC-EIC proton beamJul 02 2019Initial simulations investigating using the RHIC-EIC proton beam as the drive beam in a plasma wakefield acceleration experiment are presented. The proton beam enters the plasma and undergoes self-modulation, forming a series of microbunches. These microbunches ... More
Electron bunch generation from a plasma photocathodeJul 01 2019Plasma waves generated in the wake of intense, relativistic laser or particle beams can accelerate electron bunches to giga-electronvolt (GeV) energies in centimetre-scale distances. This allows the realization of compact accelerators having emerging ... More
Nonlinear theory of magnetohydrodynamic flows of stratified rotating plasma in two-layer shallow water approximation. Rossby waves and their three-wave interactionsJul 01 2019This article deals with rotating magnetohydrodynamic flows of a thin stratified layer of astrophysical plasma in a gravitational field with a free-surface in a vertical external magnetic field. Magnetohydrodynamic equations are obtained in the two-layer ... More
Mapping electromagnetic fields structure in plasma using a spin polarized electron beamJul 01 2019We propose a scheme to mapping electromagnetic fields structure in plasma by using a spin polarized relativistic electron beam. Especially by using Particle-in-Cell (PIC) and electron spin tracing simulations, we have successfully reconstructed a plasma ... More
Multi-photon regime of non-linear Breit-Wheeler and Compton processes in short linearly and circularly polarized laser pulsesJul 01 2019Non-linear Breit-Wheeler $e^+e^-$ pair production and its crossing channel - the non-linear Compton process - in the multi-photon regime are analyzed for linearly and circularly polarized short laser pulses. We show that (i) the azimuthal angular distributions ... More
First Results from an Event Synchronized -- High Repetition Thomson Scattering System at Wendelstein 7-XJun 30 2019The Wendelstein 7-X (W7-X) Thomson scattering (TS) diagnostic was upgraded to transiently achieve kilohertz sampling rates combined with adjustable measuring times. The existing Nd:YAG lasers are employed to repetitively emit "bursts", i.e. multiple laser ... More
Liquid-Fed Pulsed Plasma Thruster for Propelling NanosatellitesJun 29 2019This paper presents a novel micropropulsion system for nanosatellite applications - a liquid fed pulsed-plasma thruster (LF-PPT) comprised of a Lorentz-force pulsed plasma accelerator (PPA) and a low-energy surface flashover (LESF) igniter. A 3 {\mu}F ... More
Amplification of coupled nonlinear oscillations of charged particle beam in crossed magnetic fieldsJun 28 2019A non-relativistic, charged-particle beam is placed into a crossed magnetic field. For such a system, the nonlinear electrostatic oscillations generation in the different degrees of the beam freedom may be triggered by the energy/momentum exchange between ... More
Simulating the nonlinear interaction of relativistic electrons and tokamak plasma instabilities: Implementation and validation of a fluid modelJun 28 2019For the simulation of disruptions in tokamak fusion plasmas, a fluid model describing the evolution of relativistic runaway electrons and their interaction with the background plasma is presented. The overall aim of the model is to self-consistently describe ... More
On the applicability of $κ$-distributionsJun 28 2019The standard (non-relativistic) $\kappa$-distribution is widely used to fit data and to describe macroscopic thermodynamical behavior, e.g.\ the pressure (temperature) as the second moment of the distribution function. By contrast to a Maxwellian distribution, ... More
Simultaneous polarization transformation and amplification of multi-petawatt laser pulses in magnetized plasmasJun 28 2019With increasing laser peak power, the generation and manipulation of high-power laser pulses becomes a growing challenge for conventional solid-state optics due to their limited damage threshold. As a result, plasma-based optical components which can ... More
Non-stochastic electron acceleration in multipicosecond laser-solid interaction at relativistic intensityJun 27 2019We study energetic electron generation in the characteristic long underdense ion shelf and opaque plasma wall preplasma profile created by multipicosecond, relativistic intensity laser pulses incident on solid density targets. In 1D particle-in-cell simulations, ... More
Development Considerations for High-Repetition-Rate HEDP ExperimentsJun 27 2019This paper discusses experimental techniques and considerations associated with the transition to high repetition-rate experiments in High Energy Density Physics (HEDP). We particularly highlight approaches to experimentation that become practical only ... More
-8/3 spectrum in kinetic Alfvén wave turbulence: implications for the solar windJun 27 2019The nature of solar wind turbulence at large scale is rather well understood in the theoretical framework of magnetohydrodynamics. The situation is quite different at sub-proton scales where the magnetic energy spectrum measured by different spacecrafts ... More
Experimental and synthetic measurements of polarized synchrotron emission from runaway electrons in Alcator C-ModJun 26 2019This paper presents the first experimental analysis of polarized synchrotron emission from relativistic runaway electrons (REs) in a tokamak plasma. Importantly, we show that the polarization information of synchrotron radiation can be used to diagnose ... More
Symmetries of Reduced MagnetohydrodynamicsJun 26 2019Lie-symmetry methods are used to determine the symmetry group of reduced magnetohydrodynamics. This group allows for arbitrary, continuous transformations of the fields themselves, along with space-time transformations. The derivation reveals, in addition ... More
Direct-drive measurements of laser-imprint-induced shock velocity nonuniformitiesJun 25 2019Perturbations in the velocity profile of a laser-ablation-driven shock wave seeded by speckle in the spatial beam intensity (i.e., laser imprint) have been measured. Direct measurements of these velocity perturbations were recorded using a two-dimensional ... More
X-Dispersionless Maxwell solver for plasma-based particle accelerationJun 25 2019Abstract A semi-implicit finite difference time domain (FDTD) numerical Maxwell solver is presented for full electromagnetic Particle-in-Cell (PIC) codes for the simulations of plasma-based acceleration. The solver projects the volumetric Yee lattice ... More
Modulation instability of obliquely propagating ion acoustic waves in a collisionless magnetized plasma consisting of nonthermal and isothermal electronsJun 25 2019We have studied the modulation instability of obliquely propagating ion acoustic waves in a collisionless magnetized warm plasma consisting of warm adiabatic ions and two different species of electrons at different temperatures. We have derived a nonlinear ... More
Work function tuning of graphene oxide by using cesium applied to low work function tethersJun 25 2019Low Work Function Tethers (LWT) is long conductors with a segment coated with a material that has loosely-bounded electrons. Unlike a standard bare tether equipped with an active electron emitter, LWTs close the electrical circuit (cathodic contact) with ... More
The effect of RF-DC plasma N2-H2 in the selective hardening process for micro-patterned AISI420Jun 25 2019The high density of RF-DC plasma N2-H2 was used to make precise micro-texturing onto AISI420 has complex textured geometry. The original 2D micro-patterns were drawn onto substrate surface by maskless patterning using by of nano-carbon ink. These micro-patterned ... More
Experimental and Numerical Investigation of Corona Discharge Induced Flow on a Flat PlateJun 24 2019Electrohydrodynamic (EHD) flow induced by planar corona discharge in the wall boundary layer region is investigated experimentally and via a multiphysics computational model. The EHD phenomena has many potential engineering applications, its optimization ... More
Instability-enhanced transport in low temperature magnetized plasmaJun 24 2019It is shown that the transport in low temperature, collisional, bounded plasma is enhanced by instabilities at high magnetic field. While the magnetic field confines the electrons in a stable plasma, the instability completely destroys the confinement ... More
Superthermal electron generation by two-stage acceleration of backward and forward stimulated Raman scattering in high electron density regionJun 24 2019The mechanism of two-stage electron acceleration by backward stimulated Raman scattering (BSRS) and forward stimulated Raman scattering (FSRS) is demonstrated through relativistic Vlasov-Maxwell simulation. The theoretical model is given to judge the ... More
Effect of thermal ions on fluid nonlinear frequency shift of ion acoustic waves in multi-ion species plasmasJun 24 2019A model of the fluid nonlinear frequency shift of ion acoustic waves (IAWs) in multi-ion species plasmas is presented, which considers the effect of ion temperature. Because the thermal ion exists in plasmas in inertial confinement fusion (ICF) and also ... More
Burst behavior due to quasimode excited by stimulated Brillouin scattering in high-intensity laser-plasma interactionJun 24 2019The strong-coupling mode, called quasimode, will be excited by stimulated Brillouin scattering (SBS) in high-intensity laser-plasma interaction. And SBS of quasimode will compete with SBS of fast mode (or slow mode) in multi-ion species plasmas, thus ... More
HiPIMS magnetized plasma afterglow diagnosticJun 24 2019Deposition of thin films that are resistant to aggressive environment conditions, using the High-power impulse magnetron sputtering (HIPIMS) technique, represents a technological challenge. To establish the optimal operating conditions it is desirable ... More
HiPIMS magnetized plasma afterglow diagnosticJun 24 2019Jun 25 2019Deposition of thin films that are resistant to aggressive environment conditions, using the High-power impulse magnetron sputtering (HIPIMS) technique, represents a technological challenge. To establish the optimal operating conditions it is desirable ... More
Quantum backreaction in laser-driven plasmaJun 23 2019We present a new approach for investigating quantum effects in laser-driven plasma. Unlike the modelling strategies underpinning particle-in-cell codes that include the effects of quantum electrodynamics, our new field theory incorporates multi-particle ... More
Laser-plasma accelerated protons: energy increase in gas-mixtures using high mass number atomic speciesJun 22 2019The idea of using a gas-mixture comprising atoms with high mass number in order to increase proton energies in laser induced plasma acceleration at under critical density is investigated by means of 2D PIC (Particle-In-Cell) simulations. Comparing and ... More
On the Relaxed States in the Mixture of Degenerate and Non-Degenerate Hot Plasmas of Astrophysical ObjectsJun 22 2019It is shown that a small contamination of a relativistically hot electron component can induce a new scale (for structure formation) to a system consisting of an ion-degenerate electron plasma. Mathematically expression of this additional scale length ... More
High power fast pulsed magnetron dischargesJun 22 2019In order to improve the quality of thin film deposition by magnetron discharges, particularly by an effective ionization of the sputtered vapor, we developed an ionized physical vapor deposition method based on pre-ionized pulsed magnetron discharges ... More
Electron parallel closures for various ion charge numbersJun 21 2019Electron parallel closures for the ion charge number $Z=1$ [J.-Y. Ji and E. D. Held, Phys. Plasmas \textbf{21}, 122116 (2014)] are extended for $1\le Z\le10$. Parameters are computed for various $Z$ with the same form of the $Z=1$ kernels adopted. The ... More
Ion parallel closuresJun 21 2019Ion parallel closures are obtained for arbitrary atomic weights and charge numbers. For arbitrary collisionality, the heat flow and viscosity are expressed as kernel-weighted integrals of the temperature and flow-velocity gradients. Simple, fitted kernel ... More
Electron parallel closures for arbitrary collisionalityJun 21 2019Electron parallel closures for heat flow, viscosity, and friction force are expressed as kernel-weighted integrals of thermodynamic drives, the temperature gradient, relative electron-ion flow velocity, and flow-velocity gradient. Simple, fitted kernel ... More
Quantum radiation reaction in aligned crystals beyond the local constant field approximationJun 21 2019We report on experimental spectra of photons radiated by 50 GeV positrons crossing silicon single crystals of thicknesses 1.1 mm, 2.0 mm, 4.2 mm, and 6.2 mm at sufficiently small angles to the (110) planes that their motion effectively is governed by ... More
One-fluid equations of general relativistic two-fluid plasma with the Landau-Lifshitz radiation reaction force in curved spaceJun 21 2019Incorporating the radiation reaction force into two-fluid plasma in curved space, we get a set of one-fluid general relativistic magnetohydrodynamics (GRMHD) equations with the Landau-Lifshitz radiation reaction force. We analyze the importance of the ... More
Influence of atomic kinetics on inverse Bremsstrahlung heating and non-local thermal transportJun 20 2019This paper describes a computational model that self-consistently combines physics of kinetic electrons and atomic processes in a single framework. The formulation consists of a kinetic Vlasov- Boltzmann-Fokker-Planck equation for free electrons and a ... More
Influence of atomic kinetics on inverse Bremsstrahlung heating and non-local thermal transportJun 20 2019Jul 08 2019This paper describes a computational model that self-consistently combines physics of kinetic electrons and atomic processes in a single framework. The formulation consists of a kinetic Vlasov- Boltzmann-Fokker-Planck equation for free electrons and a ... More
Spatio temporal linear stability of viscoelastic free shear flows: dilute regimeJun 20 2019We report the temporal and spatio-temporal stability analyses of anti-symmetric, free shear, viscoelastic flows obeying the Oldroyd-B constitutive equation in the limit of low to moderate Reynolds number and Weissenberg number. The resulting fourth order ... More
Multi-physics simulations of lightning strike on elastoplastic substratesJun 20 2019This work is concerned with the numerical simulation of elastoplastic, electromagnetic and thermal response of aerospace materials due to their interaction with a plasma arc under lightning strike conditions. Current approaches treat the interaction between ... More
Radial Current and Rotation Profile Tailoring in Highly Ionized Linear Plasma DevicesJun 19 2019In a rotating magnetized plasma cylinder with shear, cross-field current can arise from inertial mechanisms and from the cross-field viscosity. Considering these mechanisms, it is possible to calculate the irreducible radial current draw in a cylindrical ... More
A General Metriplectic Framework with Application to Dissipative Extended MagnetohydrodynamicsJun 19 2019General equations for conservative yet dissipative (entropy producing) extended magnetohydrodynamics are derived from two-fluid theory. Keeping all terms generates unusual cross-effects, such as thermophoresis and a current viscosity that mixes with the ... More
Optical properties of magnetized transient low-pressure plasmaJun 19 2019A plasma under the influence of an external magnetic field changes the optical properties due to the Zeeman splitting of the energy levels. This splitting degenerates an initial single spectral line into a system of spectral lines with different transition ... More
Single-particle velocity distributions of collisionless, steady-state plasmas must follow SuperstatisticsJun 19 2019The correct modelling of velocity distribution functions for particles in steady-state plasmas is a central element in the study of nuclear fusion and also in the description of space plasmas. In this work, a statistical mechanical formalism for the description ... More
Stability of a force-free Hall equilibrium and release of magnetic energyJun 19 2019Conservation of magnetic helicity by the Hall drift does not prevent Hall instability of helical fields. This conclusion follows from stability analysis of a force-free spatially-periodic Hall equilibrium. The growth rates of the instability scale as ... More
Self-focusing of multiple interacting Laguerre-Gauss beams in Kerr mediaJun 18 2019Using a variational approach, we obtain the self-focusing critical power for a single and for any number of interacting Laguerre-Gauss beams propagating in a Kerr nonlinear optical medium. As is known, the critical power for freely propagating higher-order ... More
Evolution of similarity lengths in anisotropic magnetohydrodynamic turbulenceJun 18 2019In an earlier paper (Wan et al. 2012), the authors showed that a similarity solution for anisotropic incompressible 3D magnetohydrodynamic (MHD) turbulence, in the presence of a uniform mean magnetic field $\vB_0$, exists if the ratio of parallel to perpendicular ... More
Validating the ASCOT modelling of NBI fast ions in Wendelstein 7-X stellaratorJun 18 2019The first fast ion experiments in Wendelstein 7-X were performed in 2018. They are one of the first steps in demonstrating the optimised fast ion confinement of the stellarator. The fast ions were produced with a neutral beam injection (NBI) system and ... More
Improved linearized model collision operator for the highly collisional regimeJun 18 2019The linearized model collision operator for multiple species plasmas given by H. Sugama, T.-H. Watanabe, and M. Nunami [Phys.\ Plasmas {\bf 16}, 112503 (2009)] is improved to be properly applicable up to the highly collisional regime. The improved linearized ... More
Boundary Conditions for Continuum Simulations of Wall-bounded Kinetic PlasmasJun 17 2019Continuum kinetic simulations of plasmas, where the distribution function of the species is directly discretized in phase-space, permits fully kinetic simulations without the statistical noise of particle-in-cell methods. Recent advances in numerical ... More
Accelerating field enhancement due to ion motion in plasma wakefield acceleratorsJun 17 2019Ion motion in plasma wakefield accelerators can cause temporal increase of the longitudinal electric field shortly before the wave breaks. The increase is caused by re-distribution of the wave energy in transverse direction and may be important for correct ... More
Curl-free magnetic fields for stellarator optimizationJun 17 2019This paper describes a new and efficient method of defining an annular region of a curl-free magnetic field with specific physics and coil properties that can be used in stellarator design. Three statements define the importance: (1) Codes can follow ... More
Curl-free magnetic fields for stellarator optimizationJun 17 2019Jun 25 2019This paper describes a new and efficient method of defining an annular region of a curl-free magnetic field with specific physics and coil properties that can be used in stellarator design. Three statements define the importance: (1) Codes can follow ... More
Fast Magnetic Reconnection: Secondary Tearing Instability and Role of the Hall TermJun 16 2019Magnetic reconnection provides the primary source for explosive energy release, plasma heating and particle acceleration in many astrophysical environments. The last years witnessed a revival of interest in the MHD tearing instability as a driver for ... More