Design of high average power linear electron accelerator sections

An approach to a design which has a constant gradient at a lower current than the operating current is presented. This approach means that the heat can be concentrated at the input (high ν_g) end of the machine, where thermal detuning is of little consequence. Much higher conversion efficiency is obtained. In the design of these structures, changing shunt impedance has been taken into account with a model which discretely integrates the energy flow equations. A design which is constant gradient at 0.1 A has been decided upon for the Boeing High Average Power Linac