Experimental Observation of Current Generation by Unidirectional Electron Plasma Waves

Experimental observation of the blob-generation mechanism from interchange waves in a plasma.

The mechanism for blob generation in a toroidal magnetized plasma is investigated using time-resolved measurements of two-dimensional structures of electron density, temperature, and plasma potential. The blobs are observed to form from a radially elongated structure that is sheared off by the E x B flow. The structure is generated by an interchange wave that increases in amplitude and extends ...

Experimental Observation of Electron Beam Focusing through Plasma Lenses

A comprehensive experimental study of focusing of relativistic electron beams with overdense and underdense plasma lenses is being conducted at the Beam Test Facility at LBNL [1]. Short (15ps rms) electron bunches, from the 50 MeV LBNL Advanced Light Source injector are transported through laser produced plasmas. The electron beam spot size and divergence at the plasma lens is adjusted using qu...

Generation of Electron Plasma Waves in the Upstream Solar Wind

Electron plasma waves with amplitudes as high as 10 mV/m have been measured in the electron foreshock region of the earth's bow shock. It is shown that a population of stable suprathermal electrons of the type observed can produce the measured level of enhanced fluctuations without becoming unstable. The steady state wave level is given by the balancing between emission and absorption. The appa...

Observation of steepening in electron plasma waves driven by stimulated Raman backscattering.

On Generation of Unidirectional Single Steep Waves in Tanks

Abstract. Very steep waves constitute an essentially nonlinear and complicated phenomenon. Inter-related experimental and theoretical efforts are thus required to gain a better understanding of their generation and propagation mechanisms. A nonlinear focusing process in which a single unidirectional steep wave emerges from an initially wide amplitudeand frequency-modulated wave group at a predi...