13 citations · 49 across the 9 of their papers we have counts for
10 papers
Online regularization of Poincaré map of storage rings with Shannon entropy
Yongjun Li, Kelly Anderson, Derong Xu +7
Shannon entropy, as a chaos indicator, is used for online Poincaré map regularization and dynamic aperture optimization in the National Synchrotron Light Source-II (NSLS-II) ring.…
Dedicated beam position monitor pair for model-independent lattice characterization at NSLS-II
Yongjun Li, Kiman Ha, Danny Padrazo +10
This paper reports recent lattice characterization results obtained at the National Synchrotron Light Source II (NSLS-II) storage ring, conducted without reliance on a lattice mode…
Approximate Entropy Analysis for Nonlinear Beam Dynamics
Yongjun Li
In this paper, we apply approximate entropy (ApEn) analysis to the nonlinear beam dynamics in circular accelerators. Due to the presence of strong nonlinear magnets, chaos of beam…
Nonlinear optics from hybrid dispersive orbits
Yongjun Li, Derong Xu, Victor Smaluk +1
In this paper we present an expansion of the technique of characterizing nonlinear optics from off-energy orbits (NOECO) to cover harmonic sextupoles in storage rings. The existing…
Designing linear lattices for round beam in electron storage rings using the solution by linear matrices analysis
Yongjun Li, Robert Rainer
For some synchrotron light source beamline applications, a round beam is preferable to a flat one. A conventional method of obtaining round beam in an electron storage ring is to s…
Data-driven Chaos Indicator for Nonlinear Dynamics and Applications on Storage Ring Lattice Design
Yongjun Li, Jinyu Wan, Allen Liu +2
A data-driven chaos indicator concept is introduced to characterize the degree of chaos for nonlinear dynamical systems. The indicator is represented by the prediction accuracy of…
Design of double- and multi-bend achromat lattices with large dynamic aperture and approximate invariants
Yongjun Li, Kilean Hwang, Chad Mitchell +3
A numerical method to design nonlinear double- and multi-bend achromat (DBA and MBA) lattices with approximate invariants of motion is investigated. The search for such nonlinear l…
Fast dynamic aperture optimization with reversal integration
Yongjun Li, Yue Hao, Kilean Hwang +3
A fast method for dynamic aperture (DA) optimization of storage rings has been developed through the use of reversal integration. While chaotic dynamical systems have exact time-re…
Bayesian Approach for Linear Optics Correction
Yongjun Li, Robert Rainer, Weixing Cheng
With a Bayesian approach, the linear optics correction algorithm for storage rings is revisited. Starting from the Bayes' theorem, a complete linear optics model is simplified as "…
Analysis of beam position monitor requirements with Bayesian Gaussian regression
Yongjun Li, Yue Hao, Weixing Cheng +1
With a Bayesian Gaussian regression approach, a systematic method for analyzing a storage ring's beam position monitor (BPM) system requirements has been developed. The ultimate pe…