M. Castellano, M. Ferrario, F. Tazzioli, (Frascati), L. Catani, (INFN, Rome2), L. Giannessi, (ENEA, Frascati), I. Boscolo, S. Cialdi, M. Valentini, (Milan U. & INFN, Milan)
Ferroelectric PLZT ceramics are tested as photo emitters at INFN Frascati Laboratories. In order to understand the physical processes involved in the emission and to characterize them as photocathodes for use in linac injectors, it is important to measure the temporal shape of the emitted current. As the duration of the exciting laser pulse is 25 ps , the required resolution is of the order of few ps. An apparatus has been set up for the purpose, consisting of a 30 kV electron gun, a microwave transverse deflecting cavity which translates the temporal distribution of the electron bunch into a spatial one, a fluorescent screen on which the deflected beam traces a sector of a circle and various focusing and charge measuring items.The image on the screen is detected via a CCD camera and a frame grabber.We describe the performance of the apparatus and some preliminary temporal distribution measurements.
Comments or Questions to
linac2000@slac.stanford.edu