Fabrication and measurement of an X-band linear accelerator tube

Considering the challenges in fabrication and electromagnetic characterization of linear accelerator tube, first four major effective parameters in cavity fabrication, including cavity material, dimension agreement, surface roughness and concentricity of cavities have been studied. Then, considering appropriate electromagnetic properties, fabrication results of cavities, techniques for their resonant frequency and quality factor measurement are presented. Then, plunger test is done by designing special fixtures for double checking the resonant frequency of each cavity. Finally, the bead-pull test is accomplished after brazing the cavities together, to check the RF field profile and tuning.