Brazilian Journal of Physics
Print version ISSN 0103-9733
ALVES, M. Virgínia; DALLAQUA, R. S.; PRADO, F. Do and KARFIDOV, D. M.. Spectral contents of electron waves under strong Langmuir turbulence. Braz. J. Phys. [online]. 2003, vol.33, n.4, pp. 798-805. ISSN 0103-9733. http://dx.doi.org/10.1590/S0103-97332003000400033.
In this work we present experimental results of electron plasma waves excited in a beam plasma system. Based on our experimental results we determine the transition from the quasi-linear to non-linear regime. We present the space evolution of the electron beam distribution function for both regimes. The spectrum of the electron plasma wave in the non-linear regime shows a component with frequency larger than the plasma frequency besides the plasma frequency itself. We show that the higher frequency component is strongly affected by Landau damping, indicating a dissipation region. The measured experimental power spectrum of this wave shows a dependence on wave number k given by Wk µ k-7/2 as theoretically predicted.