Indirectly cooled secondary-particle production target at J-PARC Hadron Experimental Facility

The Hadron Experimental Facility at the Japan Proton Accelerator Research Complex is used for various nuclear and elementary particle physics experiments that use secondary particle beams. The secondary-particle production target is a key element for the generation of particles such as kaons and pions. To increase beam power, a new target was developed and installed. The target, which is made of gold and indirectly cooled with water, was designed so that the maximum stresses do not exceed the allowable stresses determined based on the pressure vessel standard. 95 kW is considered to be the maximum power of the primary proton beam for a 5.2-s beam duration. The new target was stably operated up to a power of 65 kW. In addition, beam position estimation based on multipoint temperature measurements of the target was demonstrated.