Current activities for research and development on accelerator-driven system in JAEA

Sugawara, Takanori  ; Nishihara, Kenji  ; Takei, Hayanori   ; Iwamoto, Hiroki   ; Oizumi, Akito   ; Sasa, Toshinobu   ; Tsujimoto, Kazufumi 

The JAEA has investigated an accelerator-driven system (ADS) to transmute minor actinides which will be partitioned from the high level waste. There are various inherent issues for the research and development on the ADS. This study introduces the current two activities to get a feasible and reliable ADS concept. For the feasibility, the beam window design is one of the most important issues. To mitigate the design condition of the beam window, namely to reduce the proton beam current, the subcritical core concepts with subcriticality adjustment mechanism were investigated. As the result, the proton beam current reduced from 20mA to 10mA by the installation of the control rods. For the reliability, the two accelerators concept was proposed and the beam trip frequency was estimated by the J-PARC LINAC data and Monte-Carlo method. Through these investigations, it was confirmed that the two accelerators concept was useful to realize reliable accelerator operation for the ADS.