The vacuum chambers for the VUV SASE FEL at the TESLA Test Facility (TTF FEL) at DESY

Abstract

A vacuum chamber for the VUV SASE FEL undulators at the TESLA Test Facility (TTF) was designed, a prototype was built and tested, and seven complete chambers were manufactured. The chambers use the aluminum extrusion technology developed for the insertion device vacuum chambers of the Advanced Photon Source. Each chamber is 4.5 m long with a beam aperture of 9.5 mm and an external thickness of 11.5 mm. Three of the chambers include ports for integral beam position monitors (10 horizontal and vertical pairs) inserted into the chambers, and all of the chambers include grooves for mounting correction coils. Bimetallic flanges (stainless steel to aluminum) are welded to the ends of the chamber for connection to the beamline. Special processing was performed to meet. The stringent vacuum and particle-free requirements of the TTF.