POP: Nonlinear Phenomena, Turbulence, Transport http://scitation.aip.org/ POP: Nonlinear Phenomena, Turbulence, Transport Nonplanar electron acoustic shock waves in a plasma with electrons featuring Tsallis distribution http://link.aip.org/link/?PHP/19/022304/1&agg=rss Biswajit Sahu and Mouloud Tribeche<br/> The properties of cylindrical and spherical electron acoustic shock waves (EASWs) in an unmagnetized plasma consisting of cold electrons, immobile ions, and hot electrons featuring Tsallis statistics are investigated by employing the reductive perturbation technique. A Korteweg-de Vries Burgers (KdV ... [Phys. Plasmas 19, 022304 (2012)] published Thu Feb 9, 2012. Nonlinear entropy transfer via zonal flows in gyrokinetic plasma turbulence http://link.aip.org/link/?PHP/19/022303/1&agg=rss M. Nakata, T.-H. Watanabe, and H. Sugama<br/> Nonlinear entropy transfer processes in toroidal ion temperature gradient (ITG) and electron temperature gradient (ETG) driven turbulence are investigated based on the gyrokinetic entropy balance relations for zonal and non-zonal modes, which are coupled through the entropy transfer function regarde ... [Phys. Plasmas 19, 022303 (2012)] published Mon Feb 6, 2012. Simulation studies of positron acceleration in a shock wave in a nonuniform external magnetic field http://link.aip.org/link/?PHP/19/022302/1&agg=rss Takashi Iwata, Seiichi Takahashi, and Yukiharu Ohsawa<br/> Positron acceleration in a shock wave in an electron-positron-ion plasma is studied with one-dimensional, fully kinetic, electromagnetic particle simulations, with particular attention paid to the effect of inhomogeneity of external magnetic field B. First, acceleration to gamma ~ 10, where gamma is ... [Phys. Plasmas 19, 022302 (2012)] published Fri Feb 3, 2012. Experimental investigation of geodesic acoustic mode spatial structure, intermittency, and interaction with turbulence in the DIII-D tokamak http://link.aip.org/link/?PHP/19/022301/1&agg=rss J. C. Hillesheim, W. A. Peebles, T. A. Carter, L. Schmitz, and T. L. Rhodes<br/> Geodesic acoustic modes (GAMs) and zonal flows are nonlinearly driven, axisymmetric (m=0andn=0) E x B flows, which are thought to play an important role in establishing the saturated level of turbulence in tokamaks. Results are presented showing the GAM's observed spatial scales, temporal scales, an ... [Phys. Plasmas 19, 022301 (2012)] published Wed Feb 1, 2012. The quench rule, Dimits shift, and eigenmode localization by small-scale zonal flows http://link.aip.org/link/?PHP/19/012315/1&agg=rss Sumire Kobayashi and Barrett N. Rogers<br/> We perform gyrokinetic simulations in a simple Z-pinch geometry to study the physics of small scale, entropy-mode-driven zonal flows. The entropy-modes create radial E x B streamers, which become unstable to the Kelvin-Helmholz (KH) instability at the point of nonlinear saturation. Sufficiently clos ... [Phys. Plasmas 19, 012315 (2012)] published Fri Jan 27, 2012. Turbulent transport of toroidal angular momentum in fusion plasmas http://link.aip.org/link/?PHP/19/012314/1&agg=rss I. Holod, Z. Lin, and Y. Xiao<br/> Global nonlinear gyrokinetic simulations of ion temperature gradient (ITG) and collisionless trapped electron mode (CTEM) turbulence find significant spinning up of a plasma in the directions opposite for CTEM and ITG turbulence. The outward momentum convection by the particle flux could be strong e ... [Phys. Plasmas 19, 012314 (2012)] published Thu Jan 26, 2012. Electron heat conduction under non-Maxwellian distribution in hohlraum simulation http://link.aip.org/link/?PHP/19/012313/1&agg=rss Wen Yi Huo<!--orlang--> (&#x970D;&#x6587;&#x4E49;)<!--orlang-->, Ke Lan<!--orlang--> (&#x84DD;&#x53EF;)<!--orlang-->, Pei Jun Gu<!--orlang--> (&#x53E4;&#x57F9;&#x4FCA;)<!--orlang-->, Heng Yong<!--orlang--> (&#x52C7;&#x73E9;)<!--orlang-->, and Qing Hong Zeng<!--orlang--> (&#x66FE;&#x6E05;&#x7EA2;)<!--orlang--><br/> An electron transport model based on the non-Maxwellian distribution f[proportional]e (NM model), caused by the inverse bremsstrahlung heating, is used in 1-D plane target and 2-D hohlraum simulations. In the NM model, the electron heat flux depends not only on the gradient of electron temperature T ... [Phys. Plasmas 19, 012313 (2012)] published Thu Jan 26, 2012. Beta dependence of electron heating in decaying whistler turbulence: Particle-in-cell simulations http://link.aip.org/link/?PHP/19/012312/1&agg=rss S. Saito and S. Peter Gary<br/> Two-dimensional particle-in-cell simulations have been carried out to study electron beta dependence of decaying whistler turbulence and electron heating in a homogeneous, collisionless magnetized plasma. Initially, applied whistler fluctuations at relatively long wavelengths cascade their energy in ... [Phys. Plasmas 19, 012312 (2012)] published Thu Jan 26, 2012. Dynamic procedure for filtered gyrokinetic simulations http://link.aip.org/link/?PHP/19/012311/1&agg=rss P. Morel, A. Banon Navarro, M. Albrecht-Marc, D. Carati, F. Merz et al.<br/> Large eddy simulations (LES) of gyrokinetic plasma turbulence are investigated as interesting candidates to decrease the computational cost. A dynamic procedure is implemented in the gene code, allowing for dynamic optimization of the free parameters of the LES models (setting the amplitudes of diss ... [Phys. Plasmas 19, 012311 (2012)] published Mon Jan 23, 2012. Modeling of asymmetric pulsed phenomena in dielectric-barrier atmospheric-pressure glow discharges http://link.aip.org/link/?PHP/19/012308/1&agg=rss Yan Ha, Huijuan Wang, and Xiaofei Wang<br/> Asymmetric current pulses in dielectric-barrier atmospheric-pressure glow discharges are investigated by a self-consistent, one-dimensional fluid model. It is found that the glow mode and Townsend mode can coexist in the asymmetric discharge even though the gas gap is rather large. The reason for th ... [Phys. Plasmas 19, 012308 (2012)] published Fri Jan 20, 2012. Electrostatic shock dynamics in superthermal plasmas http://link.aip.org/link/?PHP/19/012310/1&agg=rss S. Sultana, G. Sarri, and I. Kourakis<br/> The propagation of ion acoustic shocks in nonthermal plasmas is investigated, both analytically and numerically. An unmagnetized collisionless electron-ion plasma is considered, featuring a superthermal (non-Maxwellian) electron distribution, which is modeled by a kappa-(kappa) distribution function ... [Phys. Plasmas 19, 012310 (2012)] published Fri Jan 20, 2012. Turbulence driven particle transport in Texas Helimak http://link.aip.org/link/?PHP/19/012307/1&agg=rss D. L. Toufen, Z. O. Guimaraes-Filho, I. L. Caldas, F. A. Marcus, and K. W. Gentle<br/> We analyze the turbulence driven particle transport in Texas Helimak [K. W. Gentle and H. He, Plasma Sci. Technol. 10, 284 (2008)], a toroidal plasma device with a one-dimensional equilibrium with magnetic curvature and shear. Alterations on the radial electric field, through an external voltage bia ... [Phys. Plasmas 19, 012307 (2012)] published Fri Jan 20, 2012. Pitch angle scattering of relativistic electrons from stationary magnetic waves: Continuous Markov process and quasilinear theory http://link.aip.org/link/?PHP/19/012306/1&agg=rss Don S. Lemons<br/> We develop a Markov process theory of charged particle scattering from stationary, transverse, magnetic waves. We examine approximations that lead to quasilinear theory, in particular the resonant diffusion approximation. We find that, when appropriate, the resonant diffusion approximation simplifie ... [Phys. Plasmas 19, 012306 (2012)] published Fri Jan 20, 2012. Spatial redistribution of turbulent and mean kinetic energy http://link.aip.org/link/?PHP/19/012309/1&agg=rss P. Manz, M. Xu, N. Fedorczak, S. C. Thakur, and G. R. Tynan<br/> The turbulent spatial redistribution of turbulent and mean kinetic energy and its exchange is investigated in the framework of an K-epsilon model in a magnetized plasma column. The kinetic energy is transferred from the turbulence into the zonal flow around the shear layer. The Reynolds stress profi ... [Phys. Plasmas 19, 012309 (2012)] published Fri Jan 20, 2012. Comparison of entropy production rates in two different types of self-organized flows: Benard convection and zonal flow http://link.aip.org/link/?PHP/19/012305/1&agg=rss Y. Kawazura and Z. Yoshida<br/> Two different types of self-organizing and sustaining ordered motion in fluids or plasmasone is a Benard convection (or streamer) and the other is a zonal flowhave been compared by introducing a thermodynamic phenomenological model and evaluating the corresponding entropy production rates (EP). Thes ... [Phys. Plasmas 19, 012305 (2012)] published Wed Jan 18, 2012. Asymptotic equilibrium between Langmuir turbulence and suprathermal electrons in three dimensions http://link.aip.org/link/?PHP/19/012304/1&agg=rss Peter H. Yoon<br/> The suprathermal electron distributions with non-Maxwellian tail are commonly detected in space environment as well as in the laboratory. In a previous article [P. H. Yoon, Phys. Plasmas 18, 122303 (2011)], a self-consistent theory of asymptotically steady-state electron distribution function and La ... [Phys. Plasmas 19, 012304 (2012)] published Tue Jan 17, 2012. Interpretation of the I-Regime and transport associated with relevant heavy particle modes http://link.aip.org/link/?PHP/19/012302/1&agg=rss B. Coppi and T. Zhou<br/> The excitation of a novel kind of heavy particle [B. Coppi et al., Phys. Rev. Lett. 17, 377 (1966); B. Coppi and T. Zhou, MIT(LNS) Report HEP 09/04, 2009, Cambridge, MA [Phys. Lett. A 375, 2916 (2011)]] mode at the edge of the plasma column is considered as the signature of the I-confinement Regime ... [Phys. Plasmas 19, 012302 (2012)] published Wed Jan 11, 2012. Strong Langmuir turbulence in Kappa distributed plasmas http://link.aip.org/link/?PHP/19/012303/1&agg=rss San-Qiu Liu and Hui Chen<br/> Superthermal electrons are often observed in space and astrophysics and can be appropriate modeled by the family of Kappa distribution functions. Taking the nonlinear wave-wave, wave-particle interactions and the effect of superthermal electrons into account, the strong Langmuir turbulence is invest ... [Phys. Plasmas 19, 012303 (2012)] published Wed Jan 11, 2012. Symmetry breaking effects of density gradient on parallel momentum transport: A new rho effect http://link.aip.org/link/?PHP/19/012301/1&agg=rss Rameswar Singh, R. Singh, P. Kaw, O. D. Gurcan, P. H. Diamond et al.<br/> Symmetry breaking effects of density gradient on parallel momentum transport is studied via quasilinear theory. It is shown that finite rho([equivalent]rho/L), where rho is ion sound radius and L is density scale length, leads to symmetry breaking of the ion temperature gradient (ITG) eigenfunction. ... [Phys. Plasmas 19, 012301 (2012)] published Fri Jan 6, 2012. Electrostatic solitary structures in presence of non-thermal electrons and a warm electron beam on the auroral field lines http://link.aip.org/link/?PHP/18/122306/1&agg=rss S. V. Singh, G. S. Lakhina, R. Bharuthram, and S. R. Pillay<br/> Electrostatic solitary waves (ESWs) have been observed by satellites in the auroral region of the Earth's magnetosphere. These ESWs are found to be having both positive and negative electrostatic potentials. Using the Sagdeeev psuedo-potential technique, arbitrary amplitude electron-acoustic solitar ... [Phys. Plasmas 18, 122306 (2011)] published Thu Dec 29, 2011. On relaxation and transport in gyrokinetic drift wave turbulence with zonal flow http://link.aip.org/link/?PHP/18/122305/1&agg=rss Y. Kosuga and P. H. Diamond<br/> We present a theory for relaxation and transport in phase space for gyrokinetic drift wave turbulence with zonal flow. The interaction between phase space eddys and zonal flows is considered in two different limits, namely for K>>1 and K ~= 1 where K is the Kubo number. For K>>1, the growth of an is ... [Phys. Plasmas 18, 122305 (2011)] published Tue Dec 20, 2011.