Optimization methodology for the global 10 Hz orbit feedback in RHIC

Journal Article · Tue May 08 00:00:00 EDT 2018 · Nuclear Instruments and Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment

DOI:https://doi.org/10.1016/j.nima.2018.05.001· OSTI ID:1438429

Liu, Chuyu ^[1]; Hulsart, R. ^[1]; Mernick, K. ^[1]; Michnoff, R. ^[1]; Minty, M. ^[1]

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1. Brookhaven National Lab. (BNL), Upton, NY (United States)

To combat beam oscillations induced by triplet vibrations at the Relativistic Heavy Ion Collider (RHIC), a global orbit feedback system was developed and applied at injection and top energy in 2011, and during beam acceleration in 2012. Singular Value Decomposition (SVD) was employed to determine the strengths and currents of the applied corrections. The feedback algorithm was optimized for different magnetic configurations (lattices) at fixed beam energies and during beam acceleration. While the orbit feedback performed well since its inception, corrector current transients and feedback-induced beam oscillations were observed during the polarized proton program in 2015. In this paper, we present the feedback algorithm, the optimization of the algorithm for various lattices and the solution adopted to mitigate the observed current transients during beam acceleration.

• Research Organization: Brookhaven National Laboratory (BNL), Upton, NY (United States)
• Sponsoring Organization: USDOE; USDOE Office of Science (SC), Nuclear Physics (NP) (SC-26)
• Grant/Contract Number: AC02-98CH10886; SC0012704
• OSTI ID: 1438429
• Alternate ID(s): OSTI ID: 1582952; OSTI ID: 23064842
• Report Number(s): BNL--204652-2018-JAAM
• Journal Information: Nuclear Instruments and Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment, Journal Name: Nuclear Instruments and Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment Journal Issue: C Vol. 898; ISSN 0168-9002
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
Eigenvalue
Orbit correction
Orbit feedback
Singular value decomposition (SVD)
Tikhonov regularization
Triplet vibration