Low voltage electron beam bunching and deflection

In a Malm­berg'Pen­ning trap like EL­TRAP an elec­tron beam can be stored or prop­a­gat­ed in a space charge dom­i­nat­ed con­di­tion, due to the low ac­cel­er­a­tion volt­age used; in par­tic­u­lar we can test the lon­gi­tu­di­nal ex­pan­sion of the elec­tron bunch with sev­er­al di­ag­nos­tics, in­clud­ing Thom­son scat­ter­ing. Pulsed elec­tron beams pro­duced by an ex­ter­nal pho­to­cath­ode source in the 1'10 keV en­er­gy range and with 4 ns length have been mea­sured also by two elec­tro­stat­ic di­ag­nos­tic sys­tems. A prop­er soft­ware is need­ed to com­pen­sate for the ca­pac­i­tance of the pick­up elec­trodes. Rf can be ap­plied to the sec­tored elec­trode to pro­duce a plas­ma source or to ex­cite or to de­tect ro­ta­tion­al modes; in par­tic­u­lar the use of a new 8 sec­tor elec­trode will allow up to m=3 modes.