Ion Beam-Plasma Interaction
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Shown in the movie are color plots of the normalized electron density (normalized on the background plasma density) obtained in particle-in-cell simulations. The beam density is half of background density. The beam pulse dimensions are the beam radius is equal to 1.5 of the skin depth and half length is 7.5 of the skin depth. The beam density profile is flattop with smooth edges at 20% of the beam size. |
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The same as previous movie but shows color plots of the normalized total current in y direction. Current is normalized on the background plasma density times electron charge and speed of light. |
Movies 1 and 2 show the excitation of plasma waves during beam exit from the plasma. In contrast to the steady-state propagation, where the plasma waves establish a stationary stripe-like pattern after the beam exits the plasma, the plasma waves form a nonstationary periodic pattern, resembling butterfly-wing motion.
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The same as the first movie but for a more intense ion beam. The beam density is five times of the background density; the beam pulse dimensions are the beam radius is 1.5 of the skin depth and half length is 30 of the skin depth. Movie 3 shows the development of hose-like structures and electron holes during the beam entry, which are absent in movies 1 and 2. |