Pulse modulators for the VEPP-5 injection complex klystron power supply

In the complex VEPP-5 preinjector the klystrons are supplied by the modulators with a pulse power of 150 MW, a voltage of 47.5 kV, a primary current of 6.3 kA and a pulse duration of 3.5 ms. During the long time operation some disadvantages in the design have been revealed and proper improvements were made. The modulator design with the taking into account all the resent changes is described and test results are presented. At present, three modulators are supplying three klystrons 5045 (production of SLAC Lab., USA) and the forth modulator is tested with a dummy load in the nominal mode of operation

Tandem proton accelerator as injector for TRAPP

To inject protons to the TRAPP (synchrotron for therapy of cancer) a tandem accelerator has been constructed. Its parameters are: protons energy is 1.4 MeV, current is 3 mA, pulse duration is 2 μs, frequency is up to 1 Hz. Negative hydrogen ions are extracted through the slit from a magnetron discharge on the heated surface of the LaB6 cathode. The beam of negative ions with an initial energy of 25 kV accelerates up to the half energy in the first accelerating tube, than recharges into protons in gas nitrogen target in a tube at a potential of 700 kV. After that, the proton beam doubles its energy in the second accelerating tube. Operating and control of the tandem are by means of computer