HOM Couplers and RF Antennas for HL-LHC Crab Cavities: Developments for Manufacturing

Superconducting RF crab cavities are being manufactured as part of the High-Luminosity LHC project at CERN. Amongst its related ancillaries, radiofrequency HOM (High Order Modes) couplers and field antennas are essential for reaching nominal performance during operation with high energy beams, as they monitor and control the electromagnetic fields in the cavities. Several concepts of such equipment have been engineered and manufactured, for both design validation and RF performance assessment. The following paper highlights manufacturing process definition, its challenges and the assembly strategies focusing on the ongoing RFD prototypes for the SPS beam tests. Specific tooling development and test campaigns are also described.