Nonlinear features of electron beam-driven instabilities in a magnetized plasma

Summary form only given. Using a fully 3-dimensional parallel particle-in-cell (PPIC) code, we have studied the excitation and nonlinear evolution of plasma waves driven by an electron beam in a magnetized plasma. The transverse dimensions of the beam is varied. The early stage of the beam-driven instability shows excitation of high frequency waves near the plasma frequency. These waves quickly evolve into electron holes, which are vortexes in the phase space. This leads to nearly complete plateauing of the electron beam. At later times, a broad spectrum of waves is excited ranging from the lower hybrid to the electron plasma frequency. In time domain the waves appear as an amplitude modulated signal. An analysis of such results and the fully 3-dimensional structures of the waves will be discussed.