IPAC2018 - List of Authors (Dilly, J.)

Paper	Title	Page
MOPMF048	Aperture Measurements with AC Dipole at the Large Hadron Collider	212
	N. Fuster-Martínez, R. Bruce, J. Dilly, E.H. Maclean, T. Persson, S. Redaelli, R. Tomás CERN, Geneva, Switzerland L.J. Nevay Royal Holloway, University of London, Surrey, United Kingdom
	Global aperture measurements are crucial for a safe operation and to push the performance of the LHC, in particular, the knowledge of aperture at top energy allows pushing the optics to reduce the colliding beam sizes. The standard method used in the LHC commissioning requires using several bunches for one measurement and makes bunches un-usable for other activities. This paper presents first global aperture measurements performed at injection with a new method using the AC dipole. This method consists in exciting large coherent oscillations of the beam without spoiling its emittance. A gentle control of the oscillation amplitude enables re-using the beams for several measurements. These measurements are compared with aperture measurements performed using the standard method and possible benefits, for example for optics measurements, at top energy with squeezed optics, are elaborated.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-MOPMF048
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THPAF045	Performance Optimisation of Turn-by-Turn Beam Position Monitor Data Harmonic Analysis	3064
	L. Malina, J.M. Coello de Portugal, J. Dilly, P.K. Skowroński, R. Tomás, M.S. Toplis CERN, Geneva, Switzerland J.M. Coello de Portugal UPC, Barcelona, Spain
	Nowadays, turn-by-turn beam position monitor data is increasingly utilized in many accelerators, as it allows for fast and simultaneous measurement of various optics parameters. The accurate harmonic analysis of turn-by-turn data costs beam time when needed online. Generally, the electronic noise is avoided by cleaning of the data based on singular value decomposition. In this paper, we exploit the cleaning procedure to compress the data for the harmonic analysis. This way the harmonic analysis is sped up by an order of magnitude. The impact on measurement accuracy is discussed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAF045
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Aperture Measurements with AC Dipole at the Large Hadron Collider

212

N. Fuster-Martínez, R. Bruce, J. Dilly, E.H. Maclean, T. Persson, S. Redaelli, R. Tomás
CERN, Geneva, Switzerland
L.J. Nevay
Royal Holloway, University of London, Surrey, United Kingdom

Global aperture measurements are crucial for a safe operation and to push the performance of the LHC, in particular, the knowledge of aperture at top energy allows pushing the optics to reduce the colliding beam sizes. The standard method used in the LHC commissioning requires using several bunches for one measurement and makes bunches un-usable for other activities. This paper presents first global aperture measurements performed at injection with a new method using the AC dipole. This method consists in exciting large coherent oscillations of the beam without spoiling its emittance. A gentle control of the oscillation amplitude enables re-using the beams for several measurements. These measurements are compared with aperture measurements performed using the standard method and possible benefits, for example for optics measurements, at top energy with squeezed optics, are elaborated.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-MOPMF048

Export •

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

THPAF045

Performance Optimisation of Turn-by-Turn Beam Position Monitor Data Harmonic Analysis

3064

L. Malina, J.M. Coello de Portugal, J. Dilly, P.K. Skowroński, R. Tomás, M.S. Toplis
CERN, Geneva, Switzerland
J.M. Coello de Portugal
UPC, Barcelona, Spain

Nowadays, turn-by-turn beam position monitor data is increasingly utilized in many accelerators, as it allows for fast and simultaneous measurement of various optics parameters. The accurate harmonic analysis of turn-by-turn data costs beam time when needed online. Generally, the electronic noise is avoided by cleaning of the data based on singular value decomposition. In this paper, we exploit the cleaning procedure to compress the data for the harmonic analysis. This way the harmonic analysis is sped up by an order of magnitude. The impact on measurement accuracy is discussed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAF045

Export •

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