High-Power Test on a Cloverleaf Cavity

A one-cell plus two half-cell cloverleaf cavity similar to those suitable for a proton linear accelerator has been operated up to four times the design power to investigate sparking and heat distribution problems. This cavity was fabricated of oxygen-free high-conductivity copper forgings using techniques suitable for mass production. The power source used was a 100-kw, 800-Mc power amplifier running at 6% duty factor. No sustained sparking has been observed even at the highest power levels. Data taken on cavity clean up, equilibrating times, x-ray yield and resonant frequency versus power input are given. Details of the cavity fabrication, waveguide matching, and the waveguide vacuum window are discussed.