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  • Open Access

Sextupole reduction via chaos suppression at the National Synchrotron Light Source II

Yongjun Li*, Minghao Song, Yoshiteru Hidaka, Victor Smaluk, and Timur Shaftan

  • *Contact author: yli@bnl.gov
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Phys. Rev. Accel. Beams 29, 034001 – Published 6 March, 2026

DOI: https://doi.org/10.1103/1z4n-m4gl

Abstract

We revisit the nonlinear lattice design approach for the National Synchrotron Light Source II (NSLS-II) storage ring. By suppressing chaos, we identify alternative sextupole configurations to the original design, which relied on the conventional strategy of simultaneously minimizing resonance driving terms (RDTs) and amplitude-dependent detuning (ADD). These alternatives achieve comparable performance while requiring fewer sextupoles. A detailed comparison of two representative solutions is presented and supported by experimental validation. Our results show that the dynamic aperture correlates more strongly with global chaos than with individual RDTs, and that the importance of minimizing ADD may have been overstated in earlier design strategies.

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Phys. Rev. Accel. Beams 29, 034001– Published 6 March, 2026
  • Received 17 September 2025
  • Accepted 11 February 2026
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