Achromatic Telescopic Squeezing for Dynamic Aperture Optimization in the Electron Storage Ring of the EIC

TL;DR

This paper explores the Achromatic Telescopic Squeezing scheme to enhance dynamic aperture and momentum acceptance in the EIC's Electron Storage Ring, showing potential for sextupole reduction and improved nonlinear effects.

Contribution

It demonstrates that ATS optics can reduce sextupole strengths and improve momentum aperture, offering a novel approach for storage ring optimization.

Findings

ATS reduces sextupole requirements by a factor of two.

ATS improves momentum acceptance by approximately 0.1%.

ATS induces emittance growth due to increased beta-functions.

Abstract

We investigate the application of the Achromatic Telescopic Squeezing (ATS) scheme to the Electron Storage Ring (ESR) of the Electron-Ion Collider (EIC) as a method to improve dynamic aperture and momentum acceptance. A comparative study is performed between conventional sextupole correction schemes and ATS-based optics using both a simplified test lattice and the full ESR lattice. We show that ATS optics can reduce the required sextupole strengths and mitigate higher-order nonlinear effects, leading to improved momentum aperture. With the ATS principle one could reduce the number of sextupoles in an arcs by a factor of two while maintaining similar momentum aperture. We additionally show a scheme utilizing all sextupoles which provides an advantage in momentum aperture. While the resulting ATS optics provides a measurable increase in momentum acceptance ($\sim$0.1\% under the test conditions), it also induces emittance growth due to increased $\beta$-functions in the arcs. This trade-off limits its applicability for the ESR but suggests potential advantages for storage rings where moderate emittance growth is acceptable.