Mechanical design and testing of a magnetically coupled motion system for LHC wire scanners

Linear wire scanners are essential instruments for beam profile measurements in the Large Hadron Collider (LHC) at CERN. The current scanners installed in the machine have shown reliability and performance limitations in recent years. This work presents the development and validation of a bespoke motion system for the next-generation LHC wire scanners. The design replaces vacuum bellows with a planar magnetically coupled linear drive, coupled to a custom ceramic in-vacuum linear guide capable of high-velocity operation in ultra-high vacuum. A dedicated test rig has demonstrated the system’s positional accuracy, rigidity, and long-term durability, with over 80 000 cycles completed without degradation. This motion technology will be integrated into the first prototype scanner for impedance verification during the 2025 year end technical stop (YETS) and offers potential for wider application in demanding vacuum environments.