Development of a Cs-ceeded Rf-driven H ion source for the J-PARC

Koizumi, Isao; Ueno, Akira  ; Okoshi, Kiyonori ; Ikegami, Kiyoshi*; Takagi, Akira*; Yamazaki, Saishun; Oguri, Hidetomo  

In order to satisfy the J-PARC (Japan Proton Accelerator Research Complex) 2nd stage requirements the J-PARC rf-driven H ion source is under development. The source plasma is produced by an about 50 W CW 30 MHz-rf and an about 40 kW pulsed 2 MHz-rf. The Cs is installed into the plasma chamber by opening the Cs-valve between the plasma chamber and the Cs oven, which is heated to 200240 C. The H ion beam current is maximized by optimizing the Cs quantity depending upon the Cs-valve opening time, the PE temperature depending upon the flow rate of the air through the PE cooling plate, the AMFC by the AMFC coil current, and so on. The experimental results using the plasma chamber made of copper, which satisfied the above requirements, were reported last year. The experimental results using the plasma chamber made of stainless steel are presented in this paper. The observed several interesting differences between the two plasma chambers are also presented.