IPAC2014 - List of Authors (Li, K.S.B.)

Paper	Title	Page
TUPRO018	Prospects for the LHC Optics Measurements and Corrections at Higher Energy	1046
	R. Tomás, T. Bach, J.M. Coello de Portugal, V. Kain, M. Kuhn, A. Langner, Y.I. Levinsen, K.S.B. Li, E.H. Maclean, N. Magnin, V. Maier, M. McAteer, T. Persson, P.K. Skowroński, R. Westenberger CERN, Geneva, Switzerland E.H. Maclean JAI, Oxford, United Kingdom S.M. White BNL, Upton, Long Island, New York, USA
	LHC will resume operation in 2015 at 6.5 TeV. The higher energy allows for smaller IP beta functions, further enhancing the optics errors in the triplet quadrupoles. Moreover the uncertainty in the calibration of some quadrupoles will slightly increase due to saturation effects. The complete magnetic cycle of the LHC will take longer due to the higher energy and extended squeeze sequence. All these issues require more precise and more efficient optics measurements and corrections to guarantee the same optics quality level as in 2012 when a 7% peak beta-beating was achieved. This paper summarizes the on-going efforts for achieving faster and more accurate optics measurements and corrections.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRO018
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPRI086	Feedback System Design Techniques for Control of Intra-bunch Instabilities at the SPS	1769
	C.H. Rivetta, J.M. Cesaratto, J.E. Dusatko, J.D. Fox, O. Turgut SLAC, Menlo Park, California, USA W. Höfle, G. Kotzian, K.S.B. Li CERN, Geneva, Switzerland
	Funding: Work supported by the U.S. Department of Energy under contract # DE-AC02-76SF00515 and the US LHC Accelerator Research Program (LARP). The feedback control of intra-bunch instabilities driven by electron-clouds or strong head-tail coupling requires bandwidth sufficient to sense the vertical position and apply multiple corrections within a nanosecond-scale bunch. These requirements impose challenges and limits in the design and implementation of the feedback system. This paper presents model-based design techniques for feedback systems to address the stabilization of the transverse bunch dynamics. These techniques include in the design the effect of noise and signals perturbing the bunch motion. Different controllers are compared based on stability margins and equivalent noise gain between input-output of the processing channel. The controller design uses as example the bunch dynamics defined by the SPS ring including the Q20 optics.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRI086
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Prospects for the LHC Optics Measurements and Corrections at Higher Energy

1046

R. Tomás, T. Bach, J.M. Coello de Portugal, V. Kain, M. Kuhn, A. Langner, Y.I. Levinsen, K.S.B. Li, E.H. Maclean, N. Magnin, V. Maier, M. McAteer, T. Persson, P.K. Skowroński, R. Westenberger
CERN, Geneva, Switzerland
E.H. Maclean
JAI, Oxford, United Kingdom
S.M. White
BNL, Upton, Long Island, New York, USA

LHC will resume operation in 2015 at 6.5 TeV. The higher energy allows for smaller IP beta functions, further enhancing the optics errors in the triplet quadrupoles. Moreover the uncertainty in the calibration of some quadrupoles will slightly increase due to saturation effects. The complete magnetic cycle of the LHC will take longer due to the higher energy and extended squeeze sequence. All these issues require more precise and more efficient optics measurements and corrections to guarantee the same optics quality level as in 2012 when a 7% peak beta-beating was achieved. This paper summarizes the on-going efforts for achieving faster and more accurate optics measurements and corrections.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRO018

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPRI086

Feedback System Design Techniques for Control of Intra-bunch Instabilities at the SPS

1769

C.H. Rivetta, J.M. Cesaratto, J.E. Dusatko, J.D. Fox, O. Turgut
SLAC, Menlo Park, California, USA
W. Höfle, G. Kotzian, K.S.B. Li
CERN, Geneva, Switzerland

Funding: Work supported by the U.S. Department of Energy under contract # DE-AC02-76SF00515 and the US LHC Accelerator Research Program (LARP).
The feedback control of intra-bunch instabilities driven by electron-clouds or strong head-tail coupling requires bandwidth sufficient to sense the vertical position and apply multiple corrections within a nanosecond-scale bunch. These requirements impose challenges and limits in the design and implementation of the feedback system. This paper presents model-based design techniques for feedback systems to address the stabilization of the transverse bunch dynamics. These techniques include in the design the effect of noise and signals perturbing the bunch motion. Different controllers are compared based on stability margins and equivalent noise gain between input-output of the processing channel. The controller design uses as example the bunch dynamics defined by the SPS ring including the Q20 optics.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRI086

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)