PEPX-type lattice design and optimization for the High Energy Photon Source

TL;DR

This paper discusses the design and optimization of a PEPX-type lattice for the High Energy Photon Source, aiming to achieve diffraction-limited performance in a storage ring-based light source.

Contribution

It presents the evolution and optimization of a PEPX-type lattice specifically tailored for the High Energy Photon Source, including linear and nonlinear design considerations.

Findings

Feasibility of achieving sufficient ring acceptance for off-axis injection.

Successful design and continuous improvement of the PEPX-type lattice.

Discussion of key issues in linear optics and nonlinear optimization.

Abstract

A new generation of storage ring-based light source, called diffraction-limited storage ring (DLSR), with the emittance approaching the diffraction limit for multi-keV photons by using the multi-bend achromat lattice, has attracted worldwide and extensive studies of several laboratories, and been seriously considered as a goal of upgrading the existing facilities in the imminent future. Among various DLSR proposals, the PEPX design based on the third-order achromat concept and with the special design of a high-beta injection straight section demonstrated that, it is feasible to achieve sufficient ring acceptance for off-axis injection in a DLSR. For the High Energy Photon Source planned to be built in Beijing, PEPX-type lattice has been designed and continuously improved. In this paper, we report the evolution of the PEPX-type design, and discuss the main issues relevant to the linear optics design and nonlinear optimization.