Speaker
Description
The Accelerator Test Facility (ATF) at KEK provides a unique environment for studying nanometer-scale beam generation, measurement, and stabilization technologies for future linear colliders such as the ILC. Its 1.28 GeV ATF2 beamline was constructed to reproduce the challenging final-focus conditions expected at a linear collider interaction point. The design goal is a vertical beam size of 37 nm at ATF2, corresponding to the 7 nm beam size required at the ILC after energy scaling. A minimum vertical beam size of 41 nm has already been demonstrated, together with fast beam position feedback operating at nanometer-level precision.
Precise beam diagnostics and synchronization are essential for further progress toward stable nanobeam operation. ATF2 is equipped with a high-resolution cavity beam position monitor (cBPM) system, which has demonstrated a position resolution of about 20 nm, and an interferometric laser-based beam size monitor (IPBSM) for measuring the focused beam at the interaction point. Recent work has concentrated on improving these systems and the timing infrastructure required for their reliable operation. This report will present the current status of ATF/ATF2 and discuss recent developments of the IPBSM, upgrades of the cBPM system, and improvements to the timing and synchronization system. The ongoing work and related experimental studies are being carried out as part of the ATF3 collaboration.