Externally driven, vertically polarized transverse dust-lattice waves were observed in a one-dimensional strongly coupled dust chain levitated in the plasma-sheath boundary of a dc argon plasma at low gas pressure around 5 mtorr. Real and imaginary parts of the complex wave number were measured in the experiments. The experimental result clearly shows that the observed transverse dust-lattice w...

We describe the results from recent experiments1 on the plasma beat wave accelerator (PBWA) scheme at UCLA. A relativistic electron plasma wave (which is the accelerating structure) is resonantly excited in a plasma by the beating of two co-propagating electromagnetic waves (obtained from a CO2 laser operating simultaneously on two wavelengths). A 2 MeV, 200 mA (peak-current) electron beam, rou...

In his 1968 paper [2], R.L. Guernsey derived the dispersion relation for surface waves on a semi infinite plasma confined by a perfect reflecting wall. The aim of the current project is to extend these results to the case of a fully degenerate electron gas described by the unit step function (a limiting case of the FermiDirac distribution). By only considering the effects of the distribution fu...

We investigate the interaction of a plane, linearly polarized, Alfvénic pulse with a one-dimensional, perpendicular to the magnetic field, plasma density inhomogeneity in the strongly nonlinear regime. Our numerical study of the full MHD equations shows that: (i) Plasma density inhomogeneity substantially enhances (by about a factor of 2) the generation of longitudinal compressive waves. (ii) A...

Measurements are presented of radiated wave electric fields which result from the creation of a dense, laser-produced plasma within a large, uniform background magnetoplasma. The radiated field patterns are consistent for waves propagating along the quasielectrostatic branch of the whistler wave dispersion curve calculated from the background plasma parameters. The energy source of these waves ...

It is known that electron thermal motion in the anomalous-skin-effect regime of rf plasma discharges leads to enhancement of rf power absorption by plasma due to the resonant electron-wave interaction, which is a main mechanism of plasma heating in a typical inductively coupled plasma discharge. In this Letter we show, however, that the rf power absorption may be strongly reduced (compared to t...

We identify critical problems in Plasma Heating and Current Drive plasma-wave interaction physics and antennae concepts/technology for large fusion devices, including tokamaks, stellarators, mirror traps and constructing ITER for all major methods like ECRF, ICRF, NBI and LHH. Analysis is based on experiments in large machines and modelling with 3D ICRF and ECRF recently developed full wave PST...

Electron dephasing is a major gain-inhibiting effect in plasma-based accelerators. A novel method is proposed to overcome dephasing, in which the modulation of a modest [~O(10 kG)], axial, uniform magnetic field in the acceleration channel leads to densification of the plasma through magnetic compression, enabling direct, time-resolved control of the plasma wave properties. The methodology is b...

Absolute instability in a plasma-filled backward wave oscillator with sinusoidally corrugated slow wave structure driven by an intense relativistic electron beam has been analyzed numerically. The maximum spatial growth rate of the plasma-filled waveguide is found to be larger than that of an optimally designed vacuum structure. The excitation of a finite length structure is investigated. Altho...