Ion acoustic waves and double-layers in electronegative expanding plasmas

Ion acoustic waves and double-layers in electronegative expanding plasmas

Waves in expanding electronegative plasmas containing double layers

Expanding electronegative EN plasmas have been previously observed, experimentally, to generate wave activity. Using a particle-in-cell PIC code we have investigated these waves in expanding EN plasmas containing a double layer DL between an upstream source region and an expanded downstream region. Oxygen reaction rates were used but modified to correspond more closely to experimental condition...

Propagating double layers in electronegative plasmas

Double layers have been observed to propagate from the source region to the diffusion chamber of a helicon-type reactor filled up with a low-pressure mixture of Ar/SF6 N. Plihon et al., J. Appl. Phys. 98, 023306 2005 . In the present paper the most significant and new experimental results are reported. A fully self-consistent hybrid model in which the electron energy distribution function, the ...

Modulational instability of dust ion acoustic waves in astrophysical dusty plasmas with non thermal electrons

  Propagation of dust ion acoustic waves in plasmas composed of nonthermal distributed electrons and stationary dust particles is investigated. Nonlinear Schrdinger equation is derived to describe small amplitude waves, using the reduction perturbation technique. Modulation instability of dust ion acoustic waves is analysed for this system. Parametric investigation indicates that growth rate of...

Experimental investigation of double layers in expanding plasmas

Double layers DLs have been observed in a plasma reactor composed of a source chamber attached to a larger expanding chamber. Positive ion beams generated across the DL were characterized in the low plasma potential region using retarding field energy analyzers. In electropositive gases, DLs were formed at very low pressures between 0.1 and 1 mTorr with the plasma expansion forced by a strongly...