Design and fabrication of 33GHz high-gradient accelerators sections

As part of a two-beam accelerator research program, ∼33 GHz accelerator sections have been designed and fabricated by both the machined-and-brazed technique and the electroforming technique. These procedures are summarized in this paper. Special requirements included a filling time of about 14 ns, ±1.25μm dimensional tolerances, input VSWR ≤ 1.10, radial vacuum pumping for each cell, and a capability for a 200-300 MV/m accelerating gradient. A 34-cavity, 2π/3 mode, quasi-constant gradient, vp = c, ∼10 cm-long, disc-loaded waveguide structure design was chosen with optimized sidewall input/output iris couplers