Symmetric achromatic low-beta collider interaction region design concept

TL;DR

This paper introduces a symmetry-based achromatic low-beta interaction region design for colliders, using symmetric chromaticity compensation blocks to improve chromatic correction and beam stability.

Contribution

It presents a novel symmetric chromaticity compensation concept that reduces second-order aberrations and enhances collider interaction region performance.

Findings

Achieves simultaneous first-order chromaticity and beam smear compensation.

Reduces second-order aberrations compared to conventional methods.

Improves momentum acceptance and dynamic aperture in collider design.

Abstract

We present a new symmetry-based concept for an achromatic low-beta collider interaction region design. A specially-designed symmetric Chromaticity Compensation Block (CCB) induces an angle spread in the passing beam such that it cancels the chromatic kick of the final focusing quadrupoles. Two such CCBs placed symmetrically around an interaction point allow simultaneous compensation of the 1st-order chromaticities and chromatic beam smear at the IP without inducing significant 2nd-order aberrations to the particle trajectory. We first develop an analytic description of this approach and explicitly formulate 2nd-order aberration compensation conditions at the interaction point. The concept is next applied to develop an interaction region design for the ion collider ring of an electron-ion collider. We numerically evaluate performance of the design in terms of momentum acceptance and dynamic aperture. The advantages of the new concept are illustrated by comparing it to the conventional distributed-sextupole chromaticity compensation scheme.