3-WAVE INTERACTIONS INVOLVING ONE WHISTLER

Three-wave interactions in which one of the waves is a whistler and the other two are higher frequency waves are examined. The suggestion that radio emissions near the fundamental plasma frequency might arise in the solar corona from the coalescence of a whistler wave with a Langmuir wave is shown to be unacceptable because the resonance condition for the three-wave interaction cannot be satisfied. Modifications aimed at overcoming this objection are explored. Explicit expressions which describe the three-wave interactions are derived, and these are used to treat the scattering of transverse waves (and also of Langmuir waves) by whistlers. It is suggested that such scattering may be important in regions of the solar corona where energetic electrons are trapped.