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arXiv · 2609.07854

Design and optimization of the NSLS-II lattice with complex bend replacement

Minghao Song·Yoshiteru Hidaka·Bernard Kosciuk·Patrick N'Gotta·Sushil Sharma·Timur Shaftan·Guimei Wang
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Abstract

The demand for brighter photon beams has driven the development of diffraction-limited storage rings with ultralow electron beam emittance. A complex bend (CB) lattice was recently proposed as an approach for the future NSLS-II upgrade. As a step toward this upgrade, NSLS-II plans to replace two existing electromagnetic dipoles with permanent-magnet CBs, providing the first experimental demonstration of the CB concept in a storage ring. This paper presents the linear optics design, nonlinear optimization, and machine error evaluation of the modified NSLS-II lattice. The optimized lattice provides sufficient dynamic and momentum apertures for off-axis injection and routine operation and can be corrected with the existing NSLS-II correction scheme. Scraper measurements near the planned CB installation location validate the beam aperture requirements used in the CB design.

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Minghao Song, Yoshiteru Hidaka, Bernard Kosciuk, Patrick N'Gotta, Sushil Sharma, Timur Shaftan, Guimei Wang. 2026-09-07. Design and optimization of the NSLS-II lattice with complex bend replacement. https://arxiv.org/abs/2609.07854

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