RF Multipolar Characterization of the Latest LHC Deflecting Cavities

Deflecting cavity geometries considered for the Large Hadron Collider (LHC) crab scheme lack axial symmetry resulting in non-zero higher-order components of the deflecting field. A formalism to express the higher-order multipoles was developed and applied on previous cavity designs to characterize their influence on the beam stability. In this paper, the radio frequency (RF) multipoles are numerically estimated for the latest cavity geometries and compared to the older versions. A sensitivity study is carried out to understand the numerical errors levels and define mechanical tolerances.