Simultaneous linear optics and coupling correction for storage rings with turn-by-turn beam position monitor data

TL;DR

This paper introduces a novel method that uses turn-by-turn BPM data and ICA to simultaneously correct linear optics errors and coupling in storage rings, demonstrated on NSLS-II.

Contribution

The paper presents a new approach combining ICA and lattice fitting for concurrent correction of optics and coupling errors using TbT BPM data.

Findings

Successfully applied to NSLS-II storage ring

Accurately isolates betatron modes from BPM data

Improves storage ring lattice correction

Abstract

We propose a method to simultaneously correct linear optics errors and linear coupling for storage rings using turn-by-turn (TbT) beam position monitor (BPM) data. The independent component analysis (ICA) method is used to isolate the betatron normal modes from the measured TbT BPM data. The betatron amplitudes and phase advances of the projections of the normal modes on the horizontal and vertical planes are then extracted, which, combined with dispersion measurement, are used to fit the lattice model. The fitting results are used for lattice correction. The method has been successfully demonstrated on the NSLS-II storage ring.