抄録
Stationary one-dimensional propagation of Langmuir waves trapped in a local density cavity in a plasma is investigated for the case in which the frequency spectrum of the Langmuir waves is broad as compared with the ion acoustic frequency, but in which their wavenumbers are comparable to the inverse scale length of the density cavity. Analytical solutions for the density cavity, which traps many Langmuir wave modes and which is self-consistent with the ponderomotive potential coming from these eigenmodes, are obtained. The Langmuir wave envelopes exhibit oscillations at the beat frequencies of the different eigenmodes. These solutions are valid when the intensity of the trapped Langmuir waves normalized by the electron thermal energy is much greater than the electron-to-ion mass ratio.
