Orbit correction in a linear nonscaling fixed field alternating gradient accelerator

Abstract

In a linear nonscaling fixed field alternating gradient accelerator, the large natural chromaticity of the machine results in a betatron tune that varies by several integers over the momentum range. Orbit correction is complicated by the consequent variation of the phase advance between lattice elements. Here we investigate how the correction of multiple closed orbit harmonics allows correction of both the closed orbit distortion and the accelerated orbit distortion over the momentum range.