Abstract: A radio frequency coupler includes a waveguide having an outer conductor and an inner conductor in a coaxial tube shape. The waveguide extends linearly from a power supply side, is bent in an L shape at a bend section, and extends linearly toward an acceleration cavity. A refrigerant passage part passes through the outer conductor and the inner conductor at the bend section from the outside of the waveguide toward the acceleration cavity and is connected to the interior of the inner conductor. The refrigerant passage part has a passage tube through which refrigerant passes between the inner part of the tip on the acceleration cavity side of the inner conductor, and the outer part of the waveguide, and the portion of the passage tube that is exposed to a radio frequency transmission space formed between the outer conductor and the inner conductor being formed of an insulator.

Abstract: A radio frequency coupler includes a waveguide having an outer conductor and an inner conductor in a coaxial tube shape. The waveguide extends linearly from a power supply side, is bent in an L shape at a bend section, and extends linearly toward an acceleration cavity. A refrigerant passage part passes through the outer conductor and the inner conductor at the bend section from the outside of the waveguide toward the acceleration cavity and is connected to the interior of the inner conductor. The refrigerant passage part has a passage tube through which refrigerant passes between the inner part of the tip on the acceleration cavity side of the inner conductor, and the outer part of the waveguide, and the portion of the passage tube that is exposed to a radio frequency transmission space formed between the outer conductor and the inner conductor being formed of an insulator.

Abstract: A drift tube manufacturing method and a drift tube which can reduce cost while securing an adequate level of particle beam focusing performance. The method includes: a magnet housing stage of housing a predetermined number of permanent magnets in a housing, which has a through-hole at a center part and an annular magnet housing space on an outer circumferential side of the through-hole; a welding stage of setting a lid for covering the opening part on the opening part; and welding the lid and the housing by laser beam welding. At least a surface of the housing and a surface of the lid are formed of copper.

Abstract: The present invention provides a drift tube manufacturing method and a drift tube which can reduce cost while securing an adequate level of particle beam focusing performance. The method includes: a magnet housing stage of housing a predetermined number of permanent magnets in a housing, which has a through-hole at a center part and an annular magnet housing space on an outer circumferential side of the through-hole, from an opening part of the magnet housing space into the magnet housing space; a welding stage of setting a lid for covering the opening part on the opening part, and welding the lid and the housing by laser beam welding. At least a surface of the housing and a surface of the lid are formed of copper.