Experimental demonstration of electron beam bunching in the Arletron

We present an experimental demonstration of electron beam bunching in the new kind of compact buncher for high repetition rate high power microwaves: the Arletron. By using the code MAGIC, we have found a design in which two coupled pillbox cavities strongly bunch an annular electron beam. High repetition rate operation is possible for two reasons. First, no grids intercept the beam during its propagation and, secondly, the guiding magnetic field is low enough to be produced by a permanent magnet focusing system. Detailed comparison between MAGIC predictions and experimental results are given.