High luminosity interaction region design for collisions inside high field detector solenoid

TL;DR

This paper discusses the design and testing of a high luminosity interaction region for a collider, focusing on beam focusing, compensation mechanisms, and the challenges posed by a solenoidal field in a large detector environment.

Contribution

It introduces a novel interaction region design that effectively manages beam focusing and compensation in the presence of a strong solenoidal field, improving luminosity performance.

Findings

Successful implementation of a new compensation mechanism for beam-beam resonances.

Remarkable improvement in peak and integrated luminosity with the new design.

Effective handling of beam optics perturbations caused by the solenoidal field.

Abstract

An innovatory interaction region has been recently conceived and realized on the Frascati DA{\Phi}NE lepton collider. The concept of tight focusing and small crossing angle adopted to achieve high luminosity in multibunch collisions has evolved towards enhanced beam focusing at the interaction point with large horizontal crossing angle, thanks to a new compensation mechanism for the beam-beam resonances. The novel configuration has been tested with a small detector without solenoidal field yielding a remarkable improvement in terms of peak as well as integrated luminosity. The high luminosity interaction region has now been modified to host a large detector with a strong solenoidal field which significantly perturbs the beam optics introducing new design challenges in terms of interaction region optics design, beam transverse coupling control and beam stay clear requirements. Interaction region design criteria as well as the luminosity results relevant to the structure test are presented and discussed.