DEVELOPMENT OF 5-CELL BETA=0.9 650 MHz CAVITIES FOR PROJECT X*

Several 5-cell 650 MHz elliptical cavities have been fabricated for the PIP-II Project [1]. Two versions of the cavities have been designed to accelerate protons of relative group velocity of β=0.9 and β=0.92 in the high energy region of the linac. In this paper, we report the development status of these cavities, summarize the results of the quality control measurements performed on five initial prototypes, and outline the VTS test results.