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Ho, A. Y.

Publications and source records attributed to Ho, A. Y..

Temporal evolution of HF-enhanced plasma lines

A theoretical investigation is conducted of the temporal evolution of HF-enhanced plasma lines (HFPLs). An extended theoretical model is presented which was originally intended to explain the intensity overshoot of the high frequency enhanced plasma line (HFPL). The extension takes into consideration the fact that nonresistant heating of plasma electrons by the parametrically excited Langmuir waves can yield an apparent increment in electron temperature. It is pointed out that the HFPLs refer to the radar echoes at frequencies near the sum and difference of the radar frequency and the HF heater wave frequency. It is suggested that backscatter of radar signals from plasma waves having a wavenumber of 18/m cause the enhanced spectral lines.

Kuo, S. P.↗

A theoretical model for the temporal evolution of HF-enhanced plasma lines

The HF-enhanced plasma lines (HFPLs) observed in the Arecibo heating experiments refer to the radar returns at frequencies near the sum and difference of the radar frequency and the HF-heatear frequency. Those enhanced spectral lines are caused by backscatter of radar signals from parametrically excited plasma waves having a wavenumber of 18 n. A nonlinear theory was developed to describe the temporal evolution of those specified plasma waves and their originating altitude interval of HFPLs observed at Arecibo, Puerto Rico are explained. The theoretical resultsagree well with the observation (Djuth and Sulzer, 1989).

Kuo, S. P.↗