Measurements of the trapped particle sideband instability compared to the macroparticle model
نویسندگان
چکیده
The upper and lower sidebands are measured on a traveling wave tube where a cold electron beam is trapped by a large amplitude wave. The two strongly coupled sidebands form a normal mode that is characterized by the sideband growth rates, wave number shifts, amplitude ratio, and phase relationship. The measured values agree only qualitatively with the macroparticle model of Kruer, Dawson, and Sudan @Phys. Rev. Lett. 23, 838 ~1969!#. Also, the macroparticle model prediction for a nonlinear product wave does not agree with the experiment. Quantitative agreement is found between the experiment and computer simulations that follow the electron orbits, suggesting that the trapped particle model is too simple for quantitative predictions. © 2001 American Institute of Physics. @DOI: 10.1063/1.1379341#
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