Fabrication methods of the superconducting injector cavities for the Stanford University free electron laser

Efforts to upgrade the linac driver for the Stanford University free electron laser are described. The first stage involves the construction of a 4.0-MeV, 1-mA harmonic injector system. Fabrication methods for the fundamental 1300-MHz structures are described. Similar methods are being employed in fabrication of the third harmonic structure. The structure design and the fabrication methods combine features of the original work at Stanford University and more recent work in Europe.