E-Gun anode modulator R&D prototype for RHIC elens project

In order to increase the polarized proton luminosities, a new E-LENS system will be installed in RHIC tunnel. One of the key parts of this project is achieve a fast rise time for elens electron gun. The electron gun is driven by a fast high voltage rise time and high pulse repetition rate anode modulator. This paper will discuss some details of the modulator design concept and its simulation, problems during the test, modulator scheme modification and new modulator scheme prototype test results. Meanwhile, some test diagrams, prototype pictures and measured waveforms will be shown in the paper. The prototype test has reached the specification requirement of the modulator. The output high voltage is 10 kV, HV pulse rise and fall time is about 50nS (10%-90%) and the pulse repetition rate has reached 80 kHz.