Reflection and Transmission of Space-Charge Waves at Bunched Beam Ends

We report the experimental observation of the reflection and transmission of space-charge waves at the ends of bunched beams. The space-charge waves are produced in the form of localized perturbations on an initially rectangular electron beam which propagates in a periodic solenoid focusing channel. When the waves reach the beam ends, both reflection and transmission are observed from the experiment. The speed of the reflected and transmitted waves has been measured. A theoretical model is presented to offer an interpretation of the observed phenomena. The analysis shows that reflection does not occur if zᵣλ/π, where zᵣ is the edge length and λ is the perturbation wavelength.