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Title: Minimization of betatron oscillations of electron beam injected into a time-varying lattice via extremum seeking

Abstract

Here, we report on a beam-based experiment performed at the SPEAR3 storage ring of the Stanford Synchrotron Radiation Lightsource at the SLAC National Accelerator Laboratory, in which a model-independent extremum-seeking optimization algorithm was utilized to minimize betatron oscillations in the presence of a time-varying kicker magnetic field, by automatically tuning the pulsewidth, voltage, and delay of two other kicker magnets, and the current of two skew quadrupole magnets, simultaneously, in order to optimize injection kick matching. Adaptive tuning was performed on eight parameters simultaneously. The scheme was able to continuously maintain the match of a five-magnet lattice while the field strength of a kicker magnet was continuously varied at a rate much higher (±6% sinusoidal voltage change over 1.5 h) than typically experienced in operation. Lastly, the ability to quickly tune or compensate for time variation of coupled components, as demonstrated here, is very important for the more general, more difficult problem of global accelerator tuning to quickly switch between various experimental setups.

Authors:
ORCiD logo [1];  [2];  [2]
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  2. SLAC National Accelerator Lab., Menlo Park, CA (United States)
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1364553
Report Number(s):
LA-UR-17-20710
Journal ID: ISSN 1063-6536
Grant/Contract Number:
AC52-06NA25396; AC02-76SF00515; FWP-2013-SLAC-100164
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
IEEE Transactions on Control Systems Technology
Additional Journal Information:
Journal Volume: 26; Journal Issue: 1; Journal ID: ISSN 1063-6536
Publisher:
IEEE
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; Accelerator Design, Technology, and Operations; Mathematics; Accelerator magnets; adaptive control; electron beams; particle accelerators; particle beam handling; particle beam optics; particle beams

Citation Formats

Scheinker, Alexander, Huang, Xiaobiao, and Wu, Juhao. Minimization of betatron oscillations of electron beam injected into a time-varying lattice via extremum seeking. United States: N. p., 2017. Web. doi:10.1109/TCST.2017.2664728.
Scheinker, Alexander, Huang, Xiaobiao, & Wu, Juhao. Minimization of betatron oscillations of electron beam injected into a time-varying lattice via extremum seeking. United States. doi:10.1109/TCST.2017.2664728.
Scheinker, Alexander, Huang, Xiaobiao, and Wu, Juhao. Mon . "Minimization of betatron oscillations of electron beam injected into a time-varying lattice via extremum seeking". United States. doi:10.1109/TCST.2017.2664728. https://www.osti.gov/servlets/purl/1364553.
@article{osti_1364553,
title = {Minimization of betatron oscillations of electron beam injected into a time-varying lattice via extremum seeking},
author = {Scheinker, Alexander and Huang, Xiaobiao and Wu, Juhao},
abstractNote = {Here, we report on a beam-based experiment performed at the SPEAR3 storage ring of the Stanford Synchrotron Radiation Lightsource at the SLAC National Accelerator Laboratory, in which a model-independent extremum-seeking optimization algorithm was utilized to minimize betatron oscillations in the presence of a time-varying kicker magnetic field, by automatically tuning the pulsewidth, voltage, and delay of two other kicker magnets, and the current of two skew quadrupole magnets, simultaneously, in order to optimize injection kick matching. Adaptive tuning was performed on eight parameters simultaneously. The scheme was able to continuously maintain the match of a five-magnet lattice while the field strength of a kicker magnet was continuously varied at a rate much higher (±6% sinusoidal voltage change over 1.5 h) than typically experienced in operation. Lastly, the ability to quickly tune or compensate for time variation of coupled components, as demonstrated here, is very important for the more general, more difficult problem of global accelerator tuning to quickly switch between various experimental setups.},
doi = {10.1109/TCST.2017.2664728},
journal = {IEEE Transactions on Control Systems Technology},
number = 1,
volume = 26,
place = {United States},
year = {Mon Feb 20 00:00:00 EST 2017},
month = {Mon Feb 20 00:00:00 EST 2017}
}

Journal Article:
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