PARAMETRIC EFFECTS OF RADIATION ON A PLASMA,
Abstract
The parametric excitation of the modes of an infinite plasma by intense incident radiation is tudied on the basis of the Vlasov equation. It is found that the modes can be driven into unstable oscillations for incident frequencies in the three regions omega-nuss = approx. omega-pe, omega-pe + omega-i and 2 omega-pe where omega-pe is the electron plasma frequency, and omega-i is the ion acoustic frequency. In the limit of weak intensities, the features of the two resonances, omega-null = approx. omego-pe + omega-i and 2 omega-pe are found to be in substantial agreement with the results of DuBois and Goldman. For larger intensities it is found that the resonance omega-null = approx. omega-pe + omega-i is restricted to frequencies, omega-null, which are not more than 4 omega-pi above this value, and have a maximum growth rate of .05 omega-pe. The resonance near omega-null = approx. omega-pe is found to be dominated by collisional damping if (gamma/omega-pe) > 0.0001, and limited to a range of frequencies omega-null of only omega-pi/100. The present results, for large intensities, only partially agree with the results obtained by Silin, who only studied one of the present resonances. These results indicate that the usual harmonic approximation for the plasma is not justified in the study of optical mixing. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1966
- Accession Number
- AD0634274
Entities
People
- E. Atlee Jackson
Organizations
- University of Illinois Urbana–Champaign