Analysis of the slot heating of the coupled cavity linac cavity

CCL cavities are figures of revolution about the beam axis. An automated tuning program sets up the geometry for a symmetric accelerating cavity and runs SUPERFISH repetitively, varying the geometry to tune each cavity to the desired frequency for the electromagnetic fields. SUPERFISH solves Maxwell´s equations in 2-D. A large portion of the RF power (60-80%) applied to accelerate protons is a waste heat deposited on the inside of the copper cavity. This waste heat is removed most efficiently with water circulating through cooling passages. The waste heat needs to be removed in order to minimize thermal deformations and with it control the resonance of the cavities. A slot between the main cavity and coupled cavity receives additional heating that is not captured in the 2-D analysis. This heating causes deformation of the region and with it frequency shift. This paper covers the estimation of the slot heating and three-dimensional thermal and structural analysis of the CCL cavity