High Power Electron Beam Dump at DALS

Abstract

The electron beam dump for Dalian Advanced Light Source (DALS) is designed to absorb 15 kW of electron beam power at beam energy up to 120 MeV. The DALS accelerator produces an electron beam with very small beam size of up to 100 μA average current. The resulting beam power, up to 15 kW at 120 MeV, and the very high beam power density, pose challenging problems for beam dump design. High power dump with water cooled has been developed for DALS. In the dump, most of the beam power is finally absorbed in water and taken out from the dump. The core of the high power electron beam dump is designed to be constructed from an aluminum alloy using a cylindrical geometry with fins arranged around to promote the heat transfer. The cooling water is forced by a cooling pump, to cool the core of the dump through the cooling channels. The beam is stopped in the dump involving a high production of neutron and gamma radiation and activation of its surface. A shield has been designed to attenuate both the radiation produced during accelerator operation and the residual radiation. Design details for the dump, including radiation shielding calculations, thermal analysis are presented.