Current status of slow extraction from J-PARC Main Ring

Abstract

Abstract A 30 GeV proton beam accelerated in the J-PARC Main Ring (MR) is slowly extracted by the third integer resonant extraction and delivered to the hadron experimental facility. A dynamic bump scheme under achromatic condition drastically reduces beam hit rate on the septa devices, and we have attained 51 kW SX operation at 5.2 s cycle with high slow extraction efficiency of 99.5%. A spill duty factor indicating a uniformity of the time structure of the extracted beam is typically 50%. The current SX performance and future plans for improvements will be presented.