Development of STF beam dump

STF (Superconducting RF Test Facility) in KEK has an electron accelerator for testing of superconducting acceleration cavity. The final specification of the STF beamline accelerates electron beam with an average current of 42 μA to energy of 900 MeV. This time, we developed an aluminum alloy beam dump that can receive the STF final specification electron beam (beam power 37.8 kW) without special beam operations such as beam raster or expanding the beam size. The STF beam dump has been put into operation in March 2019. It has been confirmed that the STF beam dump operates with no problems under the current beam conditions (beam energy 280 MeV, average current 280 nA). In this report, we report on the thermal design of this STF beam dump, radiation shield design, and an overview of the operating situation. (author)