Thresholds of parametric instabilities near the lower-hybrid frequency
Resonant decay instabilities of a pump wave with frequency $omega$$sub 0$ near the lower-hybrid frequency theta/subl//subh/ are analyzed with respect to the wavenumber k of the decay waves and the ratio $omega$$sub 0$$/$$omega$/subl// subh/ to determine the decay process with the minimum threshold. It was found that the lowest thresholds are for decay into an electron plasma (lower-hybrid) wave plus either a backward ion-cyclotron wave, an ion Bernstein wave, or a low- frequency sound wave. For $omega$$sub 0$< (2$omega$/subl//subh/)$sup 1$$/$$sup 2$, it was found that these decay processes can occur and have faster growth than ion quasi-modes provided the drift velocity (cE$sub 0$/B$sub 0$) is much less than the sound speed. In many cases of interest, electromagnetic corrections to the lower-hybrid wave rule out decay into all but short wavelength (krho/subi/ >1) waves. The experimental results are consistent with the linear theory of parametric instabilities in a homogeneous plasma. (AIP)
- Research Organization:
- Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08540
- Sponsoring Organization:
- USDOE
- NSA Number:
- NSA-33-025649
- OSTI ID:
- 4023128
- Journal Information:
- Phys. Fluids, v. 19, no. 3, pp. 406-411, Other Information: Orig. Receipt Date: 30-JUN-76
- Country of Publication:
- United States
- Language:
- English
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