Physics of Plasmas: All Topics

Dynamic and spectroscopic characteristics of atmospheric gliding arc in gas-liquid two-phase flow

X. Tu, L. Yu, J. H. Yan, K. F. Cen, and B. G. Cheron
In this study, an atmospheric alternating-current gliding arc device in gas-liquid two-phase flow has been developed for the purpose of waste water degradation. The dynamic behavior of the gas-liquid gliding arc is investigated through the oscillations of electrical signals, while the spatial evolut ... [Phys. Plasmas 16, 113506 (2009)] published Fri Nov 20, 2009.

Ion flow measurements and plasma current analysis in the Irvine Field Reversed Configuration

W. S. Harris, E. Trask, T. Roche, E. P. Garate, W. W. Heidbrink et al.
Measurements of the Doppler shift of impurity lines indicate that there is an ion flow of ~7 km/s in the Irvine Field Reversed Configuration. A charge-exchange neutral particle analyzer shows the peak energy is below the 20 eV minimum detectable energy threshold, which is in agreement with the spec ... [Phys. Plasmas 16, 112509 (2009)] published Fri Nov 20, 2009.

Estimates of confinement time and energy gain for plasma liner driven magnetoinertial fusion using an analytic self-similar converging shock model

J. T. Cassibry, R. J. Cortez, S. C. Hsu, and F. D. Witherspoon
Plasma liner driven magnetoinertial fusion (PLMIF) is a fusion energy concept that utilizes an imploding plasma liner to shock heat and compress a magnetized target plasma to fusion conditions. The fusion burn fraction is linearly proportional to the confinement (or dwell) time of the liner-target s ... [Phys. Plasmas 16, 112707 (2009)] published Fri Nov 20, 2009.

Laser induced fluorescence of the ferroelectric plasma source assisted hollow anode discharge

V. Vekselman, J. Gleizer, S. Yatom, D. Yarmolich, V. Tz. Gurovich et al.
Parameters of the plasma produced by a ferroelectric plasma source (FPS) assisted high-current (~1 kA), hollow anode (HA), low-pressure (10 Torr) Ar gas discharge were studied using a time- and space-resolved laser induced fluorescence (LIF) diagnostic technique. It was shown that the plasma filli ... [Phys. Plasmas 16, 113504 (2009)] published Fri Nov 20, 2009.

The effect of parallel electric field in shock waves on the acceleration of relativistic ions, electrons, and positrons

Seiichi Takahashi, Hiromasa Kawai, Yukiharu Ohsawa, Shunsuke Usami, Charles Chiu et al.
The effect of an electric field E parallel to the magnetic field B on particle acceleration in shock waves is studied. With test particle calculations, for which the electromagnetic fields of shock waves are obtained from one-dimensional, fully kinetic, electromagnetic, particle simulations, the mot ... [Phys. Plasmas 16, 112308 (2009)] published Fri Nov 20, 2009.

Electron-cyclotron wave scattering by edge density fluctuations in ITER

Christos Tsironis, Arthur G. Peeters, Heinz Isliker, Dafni Strintzi, Ioanna Chatziantonaki et al.
The effect of edge turbulence on the electron-cyclotron wave propagation in ITER is investigated with emphasis on wave scattering, beam broadening, and its influence on localized heating and current drive. A wave used for electron-cyclotron current drive (ECCD) must cross the edge of the plasma, whe ... [Phys. Plasmas 16, 112510 (2009)] published Fri Nov 20, 2009.

On the role of a nonscalar electron pressure in the collisionless magnetic reconnection

M. Hosseinpour and G. Vekstein
Collisionless tearing instability in a sheared force-free magnetic field is considered in the framework of electron magnetohydrodynamics. A rigorous analytical analysis demonstrates that the bulk inertia of electrons is the dominant reconnection mechanism in a sufficiently low-beta plasma, when the ... [Phys. Plasmas 16, 114505 (2009)] published Fri Nov 20, 2009.

Energy coupling to the plasma in repetitive nanosecond pulse discharges

Igor V. Adamovich, Munetake Nishihara, Inchul Choi, Mruthunjaya Uddi, and Walter R. Lempert
A new analytic quasi-one-dimensional model of energy coupling to nanosecond pulse discharge plasmas in plane-to-plane geometry has been developed. The use of a one-dimensional approach is based on images of repetitively pulsed nanosecond discharge plasmas in dry air demonstrating that the plasma rem ... [Phys. Plasmas 16, 113505 (2009)] published Fri Nov 20, 2009.

Nonlinear screening effect in an ultrarelativistic degenerate electron-positron gas

N. L. Tsintsadze, A. Rasheed, H. A. Shah, and G. Murtaza
Nonlinear screening process in an ultrarelativistic degenerate electron-positron gas has been investigated by deriving a generalized nonlinear Poisson equation for the electrostatic potential. In the simple one-dimensional case, the nonlinear Poisson equation leads to Debye-like (Coulomb-like) solut ... [Phys. Plasmas 16, 112307 (2009)] published Fri Nov 20, 2009.

Guiding of 35 TW laser pulses in ablative capillary discharge waveguides

C. McGuffey, M. Levin, T. Matsuoka, V. Chvykov, G. Kalintchenko et al.
An ablatively driven capillary discharge plasma waveguide has been used to demonstrate guiding of 30 fs, 35 TW laser pulses over distances up to 3 cm with incident intensity in excess of 4 x 10 W/cm. The plasma density range over which good guiding was observed was 13 x 10 cm. The quality of the l ... [Phys. Plasmas 16, 113105 (2009)] published Thu Nov 19, 2009.

Stochastic analysis of pitch angle scattering of charged particles by transverse magnetic waves

Don S. Lemons, Kaijun Liu, Dan Winske, and S. Peter Gary
This paper describes a theory of the velocity space scattering of charged particles in a static magnetic field composed of a uniform background field and a sum of transverse, circularly polarized, magnetic waves. When that sum has many terms the autocorrelation time required for particle orbits to b ... [Phys. Plasmas 16, 112306 (2009)] published Thu Nov 19, 2009.

Parametric analysis of a magnetized cylindrical plasma

Eduardo Ahedo
The relevant macroscopic model, the spatial structure, and the parametric regimes of a low-pressure plasma confined by a cylinder and an axial magnetic field is discussed for the small-Debye length limit, making use of asymptotic techniques. The plasma response is fully characterized by three-dimens ... [Phys. Plasmas 16, 113503 (2009)] published Thu Nov 19, 2009.

Dressed soliton in quantum dusty pair-ion plasma

Prasanta Chatterjee, Kaushik Roy, S. V. Muniandy, and C. S. Wong
Nonlinear propagation of a quantum ion-acoustic dressed soliton is studied in a dusty pair-ion plasma. The Kortewegde Vries (KdV) equation is derived using reductive perturbation technique. A higher order inhomogeneous differential equation is obtained for the higher order correction. The expression ... [Phys. Plasmas 16, 112106 (2009)] published Thu Nov 19, 2009.

Fitting the dielectric response of collisionless plasmas by continued fractions

August Wierling
An approximation scheme for the dielectric response of thermal collisionless plasmas at arbitrary degeneracy is presented. A T-fraction representation is obtained from the known expansions of the real part of the dielectric function for small and large arguments. The partial numerators and denominat ... [Phys. Plasmas 16, 112105 (2009)] published Wed Nov 18, 2009.

Dust charging effects on test charge potential in a multi-ion dusty plasma

S. Ali
The DebyeHuckel and oscillatory wake potentials caused by a test charge are studied in a multi-ion dusty plasma, whose constituents are the Boltzmann distributed electrons and light positive ions, the heavy mobile negative ions, and static but charge fluctuating dust particles. For this purpose, flu ... [Phys. Plasmas 16, 113706 (2009)] published Wed Nov 18, 2009.

Dust charge and ion drag forces in a high-voltage, capacitive radio frequency sheath

I. Denysenko, K. Ostrikov, and N. A. Azarenkov
The charge of an isolated dust grain and ion drag forces on the grain in a collisionless, high-voltage, capacitive rf sheath are studied theoretically. The studies are carried out assuming that the positive ions are monoenergetic, as well as in more realistic approximation, assuming that the time-av ... [Phys. Plasmas 16, 113707 (2009)] published Wed Nov 18, 2009.

Destabilizing effect of density gradient on the KelvinHelmholtz instability

L. F. Wang, C. Xue, W. H. Ye, and Y. J. Li
In this paper, we derive explicit analytic formulas for the linear growth rate and frequency of the KelvinHelmholtz instability in fluids with the density gradient. The analytic formulas are in excellent agreement with the results of two-dimensional numerical simulation. We found that the density gr ... [Phys. Plasmas 16, 112104 (2009)] published Wed Nov 18, 2009.

Effects of trapped electrons on electromagnetic fields in an oblique shock wave

Mieko Toida and Kenta Shikii
A magnetosonic shock wave propagating obliquely to an external magnetic field can trap electrons and accelerate them to ultrarelativistic energies. The effect of trapped electrons on electromagnetic fields in a shock wave is studied by theory and particle simulations. The expressions for field stren ... [Phys. Plasmas 16, 112305 (2009)] published Wed Nov 18, 2009.

Current driven instability in collisional dusty plasmas

B. P. Pandey, S. V. Vladimirov, and A. Samarian
The current driven electromagnetic instability in a collisional, magnetized, dusty medium is considered in the present work. It is shown that in the presence of the magnetic field aligned current, the low-frequency waves in the medium can become unstable if the ratio of the current to the ambient fi ... [Phys. Plasmas 16, 113708 (2009)] published Wed Nov 18, 2009.

Long-distance correlation and zonal flow structures induced by mean E x B shear flows in the biasing H-mode at TEXTOR

Y. Xu, S. Jachmich, R. R. Weynants, M. Van Schoor, M. Vergote et al.
Long-distance toroidal correlations of potential and density fluctuations have been investigated at the TEXTOR tokamak [H. Soltwisch et al., Plasma Phys. Controlled Fusion 26, 23 (1984)] in edge electrode-biasing experiments. During the biasing-induced H-mode, the dc E x B shear flow triggers a zona ... [Phys. Plasmas 16, 110704 (2009)] published Wed Nov 18, 2009.

Neutron yield study of direct-drive, low-adiabat cryogenic D implosions on OMEGA laser system

S. X. Hu, P. B. Radha, J. A. Marozas, R. Betti, T. J. B. Collins et al.
Neutron yields of direct-drive, low-adiabat (alpha[approximate]2 to 3) cryogenic D target implosions on the OMEGA laser system [T. R. Boehly et al., Opt. Commun. 133, 495 (1997)] have been systematically investigated using the two-dimensional (2D) radiation hydrodynamics code DRACO [P. B. Radha et a ... [Phys. Plasmas 16, 112706 (2009)] published Mon Nov 16, 2009.

Erratum: Electrostatic and thermal fluctuations are the source of magnetic fields in unmagnetized inhomogeneous plasmas [Phys. Plasmas 16, 082102 (2009)]

Hamid Saleem
Abstract not available. [Phys. Plasmas 16, 119901 (2009)] published Mon Nov 16, 2009.

Relaxation of spheromak configurations with open flux

Pablo Luis Garcia-Martinez and Ricardo Farengo
The relaxation of several kink unstable equilibria with open flux representative of spheromaks sustained by dc helicity injection is studied by means of three-dimensional, resistive magnetohydrodynamic simulations. No external driving is applied, but the initial conditions are chosen to reproduce th ... [Phys. Plasmas 16, 112508 (2009)] published Mon Nov 16, 2009.

Comparison between experiment and simulation for argon inductively coupled plasma

Fei Gao, Shu-Xia Zhao, Xiao-Song Li, and You-Nian Wang
In order to include the nonlocal characteristics of electrons and investigate the inductively coupled plasma (ICP) resources more completely, we have developed a hybrid Monte Carlo (MC)/fluid hybrid model and calculated the axial and radial distributions of electron density, electron temperature, pl ... [Phys. Plasmas 16, 113502 (2009)] published Mon Nov 16, 2009.

Current sheet bifurcation and collapse in electron magnetohydrodynamics

A. Zocco, L. Chacon, and Andrei N. Simakov
Inertial effects in nonlinear magnetic reconnection are studied within the context of two-dimensional electron magnetohydrodynamics with resistive and viscous dissipation. Families of nonlinear solutions for relevant current sheet parameters are predicted and confirmed numerically in all regimes of ... [Phys. Plasmas 16, 110703 (2009)] published Mon Nov 16, 2009.

Nonthermal effects on the KarpmanWashimi ponderomotive magnetization in Lorentzian plasmas

Hwa-Min Kim and Young-Dae Jung
The nonthermal effects on the KarpmanWashimi ponderomotive magnetization are investigated in Lorentzian plasmas. The induced magnetization due to the nonstationary ponderomotive interaction related to the time variation of the field intensity is obtained as a function of the Debye length and spectra ... [Phys. Plasmas 16, 114504 (2009)] published Fri Nov 13, 2009.

Arbitrary amplitude dust ion-acoustic shock waves in a dusty plasma with positive and negative ions

A. A. Mamun, P. K. Shukla, and B. Eliasson
Arbitrary amplitude dust ion-acoustic shock waves in a multi-ion dusty plasma (composed of electrons, light positive ions, heavy negative ions, and stationary massive dust grains) has been studied. For this purpose, the coupled Poisson and dust-charging equations, which accounts for the fluctuation ... [Phys. Plasmas 16, 114503 (2009)] published Fri Nov 13, 2009.

Wall shocks in high-energy-density shock tube experiments

F. W. Doss, H. F. Robey, R. P. Drake, and C. C. Kuranz
The radiative precursor of a sufficiently fast shock has been observed to drive the vaporization of shock tube material ahead of the shock. The resulting expansion drives a converging blast wave into the gas volume of the tube. The effects of this wall shock may be observed and correlated with prima ... [Phys. Plasmas 16, 112705 (2009)] published Fri Nov 13, 2009.

Dispersive characteristics and longitudinal resonance properties in a relativistic backward wave oscillator with the coaxial arbitrary-profile slow-wave structure

Xingjun Ge, Huihuang Zhong, Baoliang Qian, Jun Zhang, Yuwei Fan et al.
The method for calculating the dispersion relations of the slow-wave structures (SWSs) with arbitrary geometrical structures is studied in detail by using the Fourier series expansion. In addition, dispersive characteristics and longitudinal resonance properties of the SWSs with the cosinusoidal, tr ... [Phys. Plasmas 16, 113104 (2009)] published Thu Nov 12, 2009.

Hot electron generation forming a steep interface in superintense laser-matter interaction

R. Mishra, Y. Sentoku, and A. J. Kemp
Superintense laser light (>10 W/cm) is able to sweep the preplasma over short times and compress the preplasma density gradient typically generated by the prepulse of today's high-intensity, high energy laser systems. Hot electron generation at steep plasma density gradients has been studied in a p ... [Phys. Plasmas 16, 112704 (2009)] published Thu Nov 12, 2009.

Effect of high-voltage nanosecond pulses on complex plasmas

M. Y. Pustylnik, A. V. Ivlev, H. M. Thomas, G. E. Morfill, L. M. Vasilyak et al.
Influence of high-voltage (111 kV) pulses of nanosecond (20 ns) duration on microparticles levitating in a rf plasma is studied. It is shown that the pulses produce significant influence on the plasma, causing perturbations with the relaxation time of the order of 10 s. This time is sufficient for ... [Phys. Plasmas 16, 113705 (2009)] published Thu Nov 12, 2009.

Nonlinear stopping power for ions moving in magnetized two-component plasmas

Zhang-Hu Hu, Yuan-Hong Song, Gui-Qiu Wang, and You-Nian Wang
Energy losses of test particles in magnetized two-component plasmas are investigated by means of particle-in-cell (PIC) simulations, taking into account the dynamic polarization effects of both the plasma ions and electrons. The influences of the magnetic field, the angle between the test particle v ... [Phys. Plasmas 16, 112304 (2009)] published Thu Nov 12, 2009.

Electron gyroscale fluctuation measurements in National Spherical Torus Experiment H-mode plasmas

D. R. Smith, S. M. Kaye, W. Lee, E. Mazzucato, H. K. Park et al.
A collective scattering system has measured electron gyroscale fluctuations in National Spherical Torus Experiment [M. Ono et al., Nucl. Fusion 40, 557 (2000)] H-mode plasmas to investigate electron temperature gradient (ETG) turbulence. Observations and results pertaining to fluctuation measurement ... [Phys. Plasmas 16, 112507 (2009)] published Wed Nov 11, 2009.

Microwave absorption of magnetized hydrogen plasma in carbon nanotubes

Afshin Moradi
A simple model to describe the microwave absorption of magnetized hydrogen plasma embedded inside the carbon nanotubes (CNTs), which were grown by iron-catalyzed high-pressure disproportionation (HiPco), is proposed and analyzed. By using Maxwell equations in conjunction with a general expression of ... [Phys. Plasmas 16, 113501 (2009)] published Wed Nov 11, 2009.

Head-on collision of ion thermal waves in a magnetized pair-ion plasma containing charged dust impurities

E. F. El-Shamy
This article presents the first study of the head-on collision between two ion thermal waves in a two-fluid (i.e., a pair-ion) magnetized plasma consisting of positive and negative ions, as well as a fraction of stationary charged dust impurities, using the extended PoincareLighthillKuo method. The ... [Phys. Plasmas 16, 113704 (2009)] published Wed Nov 11, 2009.

Plasmons with orbital angular momentum

J. T. Mendonca, S. Ali, and B. Thide
Electron plasma waves carrying orbital angular momentum are investigated in an unmagnetized collisionless plasma composed of inertial electrons and static ions. For this purpose, the usual plasmon dispersion relation is employed to derive an approximate paraxial equation. The latter is analyzed with ... [Phys. Plasmas 16, 112103 (2009)] published Wed Nov 11, 2009.

Application of variational method for three-color three-photon transitions in hydrogen atom implanted in Debye plasmas

S. Paul and Y. K. Ho
Multiphoton processes, where transparency appears, have long fascinated physicists. Plasma screening effects are investigated on three-color three-photon bound-bound transitions in hydrogen atom embedded in Debye plasmas; where photons are linearly and circularly polarized, two left circular and one ... [Phys. Plasmas 16, 113301 (2009)] published Wed Nov 11, 2009.

Experimental observation of carbon dioxide reduction in exhaust gas from hydrocarbon fuel burning

Han S. Uhm and Chul H. Kim
A high-negative voltage at the cathode initiates a dark discharge, resulting in a reduction of the carbon dioxide concentration in exhaust gas from the burning of hydrocarbon fuel. An experiment indicated that nearly 44% of the carbon dioxide in exhaust gas disappears after a high-voltage applicatio ... [Phys. Plasmas 16, 114502 (2009)] published Wed Nov 11, 2009.

Fast reconnection in high-Lundquist-number plasmas due to the plasmoid Instability

A. Bhattacharjee, Yi-Min Huang, H. Yang, and B. Rogers
Thin current sheets in systems of large size that exceed a critical value of the Lundquist number are unstable to a super-Alfvenic tearing instability, referred to hereafter as the plasmoid instability. The scaling of the growth rate of the most rapidly growing plasmoid instability with respect to t ... [Phys. Plasmas 16, 112102 (2009)] published Wed Nov 11, 2009.

Hollow current profile scenarios for advanced tokamak reactor operations

P.-A. Gourdain and J.-N. Leboeuf
Advanced tokamak scenarios are a possible approach to boosting reactor performances. Such schemes usually trigger current holes, a particular magnetohydrodynamics equilibrium where no current or pressure gradients exist in the core of the plasma. While such equilibria have large bootstrap fractions, ... [Phys. Plasmas 16, 112506 (2009)] published Tue Nov 10, 2009.

Size scaling effects on the particle density fluctuations in confined plasmas

Federico Vazquez and Ferenc Markus
In this paper, memory and nonlocal effects on fluctuating mass diffusion are addressed in the context of fusion plasmas. Nonlocal effects are included by considering a diffusivity coefficient depending on the size of the container in the transverse direction to the applied magnetic field. It is obta ... [Phys. Plasmas 16, 112303 (2009)] published Tue Nov 10, 2009.

Energy gain of free electron in pulsed electromagnetic plane wave with constant external magnetic fields

Justin Angus and Sergei Krasheninnikov
The interactions of a relativistic free electron with a pulsed electromagnetic (EM) plane wave in the presence of constant magnetic fields are studied using the well-known constants of motion. The goal is to determine the energy gained by the electron after the wave has passed. For a constant magnet ... [Phys. Plasmas 16, 113103 (2009)] published Tue Nov 10, 2009.

Geometry dependence of stellarator turbulence

H. E. Mynick, P. Xanthopoulos, and A. H. Boozer
Using the nonlinear gyrokinetic code package GENE/GIST [F. Jenko, W. Dorland, M. Kotschenreuther, and B. N. Rogers, Phys. Plasmas 7, 1904 (2000); P. Xanthopoulos, W. A. Cooper, F. Jenko, Yu. Turkin, A. Runov, and J. Geiger, ibid. 16, 082303 (2009)], we study the turbulent transport in a broad family ... [Phys. Plasmas 16, 110702 (2009)] published Tue Nov 10, 2009.

Obliquely propagating cnoidal waves in a magnetized dusty plasma with variable dust charge

L. L. Yadav and V. K. Sayal
We have studied obliquely propagating dust-acoustic nonlinear periodic waves, namely, dust-acoustic cnoidal waves, in a magnetized dusty plasma consisting of electrons, ions, and dust grains with variable dust charge. Using reductive perturbation method and appropriate boundary conditions for nonlin ... [Phys. Plasmas 16, 113703 (2009)] published Thu Nov 5, 2009.

Transport of energy by ultraintense laser-generated electrons in nail-wire targets

T. Ma, M. H. Key, R. J. Mason, K. U. Akli, R. L. Daskalova et al.
Nail-wire targets (20 [mu]m diameter copper wires with 80 [mu]m hemispherical head) were used to investigate energy transport by relativistic fast electrons generated in intense laser-plasma interactions. The targets were irradiated using the 300 J, 1 ps, and 2 x 10 Wcm Vulcan laser at the Ruther ... [Phys. Plasmas 16, 112702 (2009)] published Wed Nov 4, 2009.

Dust negative ion acoustic shock waves in a dusty multi-ion plasma with positive dust charging current

S. S. Duha
Recent analysis of Mamun et al. [ Phys. Lett. A 373, 2355 (2009)], who considered electrons, light positive ions, heavy negative ions, and extremely massive (few micron size) charge fluctuating dust, has been extended by positive dust charging current, i.e., considering the charging currents for po ... [Phys. Plasmas 16, 113701 (2009)] published Wed Nov 4, 2009.

Technique for analysis of interparticle interaction in nonideal dissipative systems with isotropic pair potentials

O. S. Vaulina and E. A. Lisin
A new technique for determining interaction forces between the particles in nonideal dissipative systems with isotropic pair potentials is presented. This technique is based on solving of the inverse problem describing movement of dust particles by a system of Langevin equations. Numerical simulatio ... [Phys. Plasmas 16, 113702 (2009)] published Wed Nov 4, 2009.

Linearized model collision operators for multiple ion species plasmas and gyrokinetic entropy balance equations

H. Sugama, T.-H. Watanabe, and M. Nunami
Linearized model collision operators for multiple ion species plasmas are presented that conserve particles, momentum, and energy and satisfy adjointness relations and Boltzmann's H-theorem even for collisions between different particle species with unequal temperatures. The model collision operator ... [Phys. Plasmas 16, 112503 (2009)] published Wed Nov 4, 2009.

Enhancement of backward Raman scattering by electron-ion collisions

Z. J. Liu, Shao-ping Zhu, L. H. Cao, C. Y. Zheng, X. T. He et al.
The propagation of light waves in an underdense plasma is studied using one-dimensional VlasovMaxwell numerical simulation. It is found that the backward stimulated Raman scattering will be enhanced by electron-ion collisions. With appropriate electron-ion collision rate the Langmuir waves, driven v ... [Phys. Plasmas 16, 112703 (2009)] published Wed Nov 4, 2009.

Coupled nonlinear drift and ion acoustic waves in dense dissipative electron-positron-ion magnetoplasmas

W. Masood, S. Karim, H. A. Shah, and M. Siddiq
Linear and nonlinear propagation characteristics of drift ion acoustic waves are investigated in an inhomogeneous electron-positron-ion (e-p-i) quantum magnetoplasma with neutrals in the background using the well known quantum hydrodynamic model. In this regard, Kortewegde VriesBurgers (KdVB) and Ka ... [Phys. Plasmas 16, 112302 (2009)] published Wed Nov 4, 2009.

Validity of closed periodic magnetic focusing for sheet electron beams

Ding Zhao
Theoretical analyses and numerical calculations have demonstrated that a closed periodic cusped magnetic (PCM) field can effectively confine a sheet electron beam in two transverse directions (i.e., in the wide and narrow dimensions, simultaneously) for stable long distance transport in which the si ... [Phys. Plasmas 16, 113102 (2009)] published Tue Nov 3, 2009.

Steady state self-induced current in tokamak

Yu. V. Gott and E. I. Yurchenko
A model, which may make it possible to self-consistently calculate the self-driven current in tokamaks taking into account asymmetry and bootstrap currents, is presented. It is shown that the described self-driven current can provide steady-state tokamak operation without the seed current produced w ... [Phys. Plasmas 16, 112502 (2009)] published Tue Nov 3, 2009.

Counter-facing plasma focus system as a repetitive and/or long-pulse high energy density plasma source

Yutaka Aoyama, Mitsuo Nakajima, and Kazuhiko Horioka
A plasma focus system composed of a pair of counter-facing coaxial plasma guns is proposed as a long-pulse and/or repetitive high energy density plasma source. A proof-of-concept experiment demonstrated that with an assist of breakdown and outer electrode connections, current sheets evolved into a c ... [Phys. Plasmas 16, 110701 (2009)] published Tue Nov 3, 2009.

A closure scheme for modeling rf modifications to the fluid equations

C. C. Hegna and J. D. Callen
A procedure to include the effects of externally applied rf sources in a comprehensive fluid model is outlined. The fluid equations are derived from moments of a kinetic equation that includes the effects of an rf source. In general, this source produces additional terms in each of the fluid equatio ... [Phys. Plasmas 16, 112501 (2009)] published Mon Nov 2, 2009.

Onset and saturation of backward stimulated Raman scattering of laser in trapping regime in three spatial dimensions

L. Yin, B. J. Albright, H. A. Rose, K. J. Bowers, B. Bergen et al.
A suite of three-dimensional (3D) VPIC [K. J. Bowers et al., Phys. Plasmas 15, 055703 (2008)] particle-in-cell simulations of backward stimulated Raman scattering (SRS) in inertial confinement fusion hohlraum plasma has been performed on the heterogeneous multicore supercomputer, Roadrunner, present ... [Phys. Plasmas 16, 113101 (2009)] published Mon Nov 2, 2009.

Anomalous transport of energetic particles in ITER relevant scenarios

M. Albergante, J. P. Graves, A. Fasoli, F. Jenko, and T. Dannert
The anomalous transport of energetic ions in the presence of turbulent fields is investigated. Nonlinear simulations of a steady-state ITER [R. Aymar et al., Nucl. Fusion 41, 1301 (2001)] scenario have been carried out using the gyrokinetic turbulence code GENE [F. Jenko et al., Phys. Plasmas 7, 190 ... [Phys. Plasmas 16, 112301 (2009)] published Mon Nov 2, 2009.

Spherical RayleighTaylor growth of three-dimensional broadband perturbations on OMEGA

V. A. Smalyuk, S. X. Hu, J. D. Hager, J. A. Delettrez, D. D. Meyerhofer et al.
Spherical RayleighTaylor (RT) growth experiments of three-dimensional (3D) broadband nonuniformities were conducted in the acceleration phase of spherical implosions on OMEGA [T. R. Boehly et al., Opt. Commun. 133, 495 (1997)]. The targets consisted of 20- and 24-[mu]m-thick plastic spherical shells ... [Phys. Plasmas 16, 112701 (2009)] published Mon Nov 2, 2009.

Langmuir wave linear evolution in inhomogeneous nonstationary anisotropic plasma

I. Y. Dodin, V. I. Geyko, and N. J. Fisch
A hydrodynamic equation describing the linear evolution of a nondissipative Langmuir wave in inhomogeneous nonstationary anisotropic plasma without magnetic field is derived in the geometrical optics approximation. The continuity equation for the wave action density, anticipated from general princip ... [Phys. Plasmas 16, 112101 (2009)] published Mon Nov 2, 2009.

Electrostatic drift modes in quantum dusty plasmas with Jeans terms

Haijun Ren, Zhengwei Wu, Jintao Cao, and Paul K. Chu
Electrostatic drift waves (EDWs) are investigated in nonuniform quantum magnetized dusty plasmas by taking into account dust gravitational effects with the help of the quantum hydrodynamic model. Ions and electrons are viewed as low-temperature Fermi gases, whereas quantum effects are neglected for ... [Phys. Plasmas 16, 103705 (2009)] published Fri Oct 30, 2009.

Extension of the electron dissipation region in collisionless Hall magnetohydrodynamics reconnection

Brian P. Sullivan, A. Bhattacharjee, and Yi-Min Huang
This paper presents SweetParker type scaling arguments in the context of hyper-resistive Hall magnetohydrodynamics. Numerical experiments suggest that both cusplike and modestly more extended geometries are realizable. However, the length of the electron dissipation region, which is taken as a param ... [Phys. Plasmas 16, 102111 (2009)] published Fri Oct 30, 2009.

Characteristics of a velvet cathode under high repetition rate pulse operation

Tao Xun, Jian-De Zhang, Han-Wu Yang, Zi-Cheng Zhang, and Yu-Wei Fan
As commonly used material for cold cathodes, velvet works well in single shot and low repetition rate (rep-rate) high-power microwave (HPM) sources. In order to determine the feasibility of velvet cathodes under high rep-rate operation, a series of experiments are carried out on a high-power diode, ... [Phys. Plasmas 16, 103106 (2009)] published Fri Oct 30, 2009.

Stabilization of the potential multi-steady-state absolute instabilities in a gyrotron traveling-wave amplifier

Chao-Hai Du and Pu-Kun Liu
The problem of spurious oscillations induced by absolute instabilities is the most challenging one that hinders the development of the millimeter-wave gyrotron traveling-wave amplifiers (gyro-TWTs). A spurious oscillation exists as a high order axial mode (HOAM) in the interaction circuit. This pape ... [Phys. Plasmas 16, 103107 (2009)] published Fri Oct 30, 2009.

Quantum effects on the dispersion of ion acoustic waves

A. Mushtaq and D. B. Melrose
The longitudinal response function for an isotropic, nonrelativistic, thermal plasma with the quantum recoil included exactly is used to generalize the dispersion relation for ion acoustic waves and the absorption coefficient for Landau damping to include the quantum recoil. The results are compared ... [Phys. Plasmas 16, 102110 (2009)] published Fri Oct 30, 2009.

Resonant excitation of shear Alfven perturbations by trapped energetic ions in a tokamak

I. G. Abel, B. N. Breizman, S. E. Sharapov, and JET-EFDA Contributors
A new analytic expression is derived for the resonant drive of high n Alfvenic modes by particles accelerated to high energy by ion cyclotron resonance heating. This derivation includes finite orbit effects, and the formalism is completely nonperturbative. The high-n limit is used to calculate the c ... [Phys. Plasmas 16, 102506 (2009)] published Fri Oct 30, 2009.

Random walk of electrons in a gas in the presence of polarized electromagnetic waves: Genesis of a wave induced discharge

Sudeep Bhattacharjee and Samit Paul
The average number of collisions N of seed electrons with neutral gas atoms during random walk in escaping from a given volume, in the presence of polarized electromagnetic waves, is found to vary as N=B(Lambda/lambda)/[1+C(Lambda/lambda)], indicating a modification to the conventional field free sq ... [Phys. Plasmas 16, 104502 (2009)] published Fri Oct 30, 2009.

Efficient generation of quasimonoenergetic ions by Coulomb explosions of optimized nanostructured clusters

M. Murakami and K. Mima
Coulomb explosion of spherical ion clusters is studied, which are composed of homogeneous two-species (light and heavy) ions. A simple analytical model is developed to describe the explosion performance in terms of two dimensionless parameters, the charge-over-mass ratio, and the charge density rati ... [Phys. Plasmas 16, 103108 (2009)] published Fri Oct 30, 2009.

Magnetic multipole induced zero-rotation frequency bounce-resonant loss in a PenningMalmberg trap used for antihydrogen trapping

G. B. Andresen, W. Bertsche, C. C. Bray, E. Butler, C. L. Cesar et al. ALPHA Collaboration
In many antihydrogen trapping schemes, antiprotons held in a short-well PenningMalmberg trap are released into a longer well. This process necessarily causes the bounce-averaged rotation frequency [overline Omega ] of the antiprotons around the trap axis to pass through zero. In the presence of a t ... [Phys. Plasmas 16, 100702 (2009)] published Fri Oct 30, 2009.

Magnetothermal instability of plasmas in a horizontal magnetic field

Haijun Ren, Zhengwei Wu, Jintao Cao, and Paul K. Chu
The linear buoyancy instability in a magnetized plasma, generally referred to as magnetothermal instability (MTI), is investigated by considering anisotropic heat conduction. The external magnetic field is assumed to be horizontal and background heat flux is not taken into account. The general dispe ... [Phys. Plasmas 16, 102109 (2009)] published Thu Oct 29, 2009.

On the effect of rear-surface dielectric coatings on laser-driven proton acceleration

S. Betti, C. A. Cecchetti, E. Forster, A. Gamucci, A. Giulietti et al.
Laser-driven ion acceleration has been experimentally investigated by irradiating, with tightly focused femtosecond laser pulses at 5 x 10 W/cm, thin metal foils, which have been back-coated with a [mu]m thick dielectric layer. The observation we report shows the production of MeV proton bunches wi ... [Phys. Plasmas 16, 100701 (2009)] published Thu Oct 29, 2009.

Kinetic Alfven waves turbulence in the Earth's magnetosphere

Sachin Kumar and R. P. Sharma
The numerical simulations of the model equation governing the nonlinear dynamics of kinetic Alfven waves in the intermediate-beta plasmas are performed. When the nonlinearity arises due to the ponderomotive force driven density perturbations of kinetic Alfven waves, the model equation turns out to b ... [Phys. Plasmas 16, 102904 (2009)] published Wed Oct 28, 2009.

Effect of energetic electrons on near-wall sheath voltage in the cathode region of a cold cathode direct current discharge

J. Blessington, S. F. Adams, V. I. Demidov, and J. M. Williamson
It is experimentally demonstrated that energetic electrons originating from the cathode or produced in volumetric processes in the cathode region of a cold cathode direct current discharge can create a large potential drop in the near-wall sheath. This voltage drop may be much greater than kT/e (whe ... [Phys. Plasmas 16, 104501 (2009)] published Wed Oct 28, 2009.

Unified theory of resistive and inertial ballooning modes in three-dimensional configurations

T. Rafiq, C. C. Hegna, J. D. Callen, and A. H. Kritz
Analytic results for the stability of resistive ballooning modes (RBMs) and electron inertial ballooning modes are obtained using a two-scale analysis. This work generalizes previous calculations used for axisymmetric salpha geometry [R. H. Hastie, J. J. Ramos, and F. Porcelli, Phys. Plasmas 10, 440 ... [Phys. Plasmas 16, 102505 (2009)] published Wed Oct 28, 2009.

Oscillations of the collisionless sheath at grazing incidence of the magnetic field

M. Shoucri, H. Gerhauser, and K. H. Finken
An Eulerian Vlasov code is used to study the physics of a collisionless sheath with grazing angles of incidence of the magnetic field. The electrons are treated with a parallel-B kinetic equation. In the case where the ion gyroradius is large compared to the Debye length, the electrons, frozen by th ... [Phys. Plasmas 16, 103506 (2009)] published Wed Oct 28, 2009.

Evolution of Alfvenic wave envelopes in spin-1/2 quantum Hall-magnetohydrodynamic plasmas

A. P. Misra, N. K. Ghosh, and P. K. Shukla
The one-dimensional oblique propagation of large amplitude magnetohydrodynamic (MHD) waves in a high-beta quantum Hall-MHD plasma is studied with electron spin-1/2 effects. The plasma beta becomes high by the condition for the nonrelativistic fluid model to be valid and the condition for the collect ... [Phys. Plasmas 16, 102309 (2009)] published Wed Oct 28, 2009.

Parameters of a collisional radio-frequency sheath and dust characteristics resulting from the microparticle levitation

V. V. Yaroshenko, T. Antonova, H. M. Thomas, and G. E. Morfill
The screening length, the time-average electric field, and the particle charge as well as the local vertical gradients of these quantities are determined experimentally within a sheath of a capacitively coupled rf, 13.56 MHz, discharge at enhanced argon gas pressures of 30, 55, and 100 Pa. The param ... [Phys. Plasmas 16, 103505 (2009)] published Tue Oct 27, 2009.

Magnetic field and electromagnetic wave properties of carbon monoxide with high-pressure disproportionation single-walled carbon nanotubes

S. B. Tooski
A double-fluid theory is used to find the electromagnetic wave absorption of carbon monoxide with iron-catalyzed high-pressure disproportionation (HiPco)-grown single-walled carbon nanotubes (SWNTs). The electromagnetic wave absorption of carbon monoxide with HiPco SWNTs is obtained and is studied n ... [Phys. Plasmas 16, 103302 (2009)] published Tue Oct 27, 2009.

Runaway electron transport via tokamak microturbulence

T. Hauff and F. Jenko
The mechanisms found for the magnetic transport of fast ions in the work of Hauff et al. [Phys. Rev. Lett. 102, 075004 (2009)] are extended to the diffusion of runaway electrons. Due to their smaller mass and larger energy, they behave strongly relativistically, for which reason the scaling laws def ... [Phys. Plasmas 16, 102308 (2009)] published Tue Oct 27, 2009.