Multipactor in 4 rod crab cavities

Multipactor is a limiting factor in many SRF cavities due to the additional heat load and power absorption. In this paper we study multipactor in 4 rod crab cavities, which have deflecting rather than accelerating fields. The particles are tracked in CST Particle Studio for three different secondary emission yields (SEY) to differentiate between hard and soft multipacting barriers. It is shown that multipacting barriers exist at a transverse voltage of 2 MV for high SEY materials but that these trajectories do not appear with lower SEY materials suggesting that they will process away.