Speaker
Description
At the KEK ATF, beam diagnostics and control technologies are being developed to achieve a 37 nm vertical beam size and to demonstrate the final-focus scheme for the ILC. Precise positioning of sextupole magnets is essential for correcting beam optics in the Final Focus (FF) beamline and achieving the target beam size. Particle-tracking simulations have shown that the sextupole magnet movers require a positioning repeatability better than approximately 1 μm. However, the aging mover system exhibited degraded repeatability, particularly for displacements exceeding 100 μm. To improve performance, the control system was upgraded with encoder feedback and calibrated control parameters. As a result, the positioning repeatability was significantly improved. We present the upgraded magnet mover system and its position-control performance.