IPAC2016 - List of Keywords (ground-motion)

Paper	Title	Other Keywords	Page
TUPMW012	Beam Offset Stabilization Techniques for the LHC Collision Points	luminosity, experiment, optics, operation	1438
	A.A. Gorzawski, R. Jacobsson, J. Wenninger CERN, Geneva, Switzerland
	Maintaining head-on collisions over many hours is an important aspect of optimizing the performance of a collider. For current LHC operation where the beam optics is fixed during periods of colliding beam, mainly ground motion induced perturbations have to be compensated. The situation will become significantly more complex when luminosity leveling will be applied following the LHC luminosity upgrades. During β^* leveling the optics in the interaction region changes significantly, feed-downs from quadrupole misalignment may induce significant orbit changes that may lead to beam offsets at the collision points. Such beam offsets induce a loss of luminosity and reduce the stability margins for collective effects that is provided by head-on beam-beam. It is therefore essential that the beam offsets at the collision points are minimized during the leveling process. This paper will review sources and mitigation techniques for the orbit perturbation at the collision points during β^* leveling, and present results of experiments performed at the LHC to mitigate and compensate such offsets.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMW012
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WEPOR005	Ground Motion Compensation using Feed-forward Control at ATF2	quadrupole, controls, extraction, feedback	2670
	D.R. Bett, C. Charrondière, M. Patecki, J. Pfingstner, D. Schulte, R. Tomás CERN, Geneva, Switzerland A. Jeremie IN2P3-LAPP, Annecy-le-Vieux, France K. Kubo, S. Kuroda, T. Naito, T. Okugi, T. Tauchi, N. Terunuma KEK, Ibaraki, Japan
	Ground motion compensation using feed-forward control is a novel technique being developed to combat beam imperfections resulting from the vibration-induced misalignment of beamline components. The method is being evaluated experimentally at the KEK Accelerator Test Facility 2 (ATF2). It has already been demonstrated that the beam position correlates with the readings from a set of seismometers located along the beamline. To compensate for this contribution to the beam jitter, the fully operational system will use realtime measurement and processing in order to calculate and apply the feed-forward correction on a useful time scale. The progress towards a working system is presented in this paper.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOR005
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WEPOR009	Intra-beam IP Feedback Studies for the 380 GeV CLIC Beam Delivery System	luminosity, feedback, kicker, simulation	2683
	R.M. Bodenstein, P. Burrows, J. Snuverink JAI, Oxford, United Kingdom F. Plassard CERN, Geneva, Switzerland
	In its currently-envisaged initial stage, the Compact Linear Collider (CLIC) will collide beams with a 380 GeV center of mass energy. To maintain the luminosity within a few percent of the design value, beam stability at the interaction point (IP) must be controlled at the sub-nanometer level. To help achieve such control, use of an intra-pulse IP feedback system is planned. With CLIC's very short bunch spacing of 0.5 ns, and nominal pulse duration of 176 ns, this feedback system presents a significant technical challenge. Furthermore, as part of a study to optimize the design of the beam delivery system (BDS), several L* configurations have been studied. In this paper, we will review the IP feedback simulations for the 380 GeV machine for two L* configurations, and compare luminosity recovery performance with that of the original L* configuration in the 3 TeV machine.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOR009
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Paper

Title

Other Keywords

Page

TUPMW012

Beam Offset Stabilization Techniques for the LHC Collision Points

luminosity, experiment, optics, operation

1438

A.A. Gorzawski, R. Jacobsson, J. Wenninger
CERN, Geneva, Switzerland

Maintaining head-on collisions over many hours is an important aspect of optimizing the performance of a collider. For current LHC operation where the beam optics is fixed during periods of colliding beam, mainly ground motion induced perturbations have to be compensated. The situation will become significantly more complex when luminosity leveling will be applied following the LHC luminosity upgrades. During β^* leveling the optics in the interaction region changes significantly, feed-downs from quadrupole misalignment may induce significant orbit changes that may lead to beam offsets at the collision points. Such beam offsets induce a loss of luminosity and reduce the stability margins for collective effects that is provided by head-on beam-beam. It is therefore essential that the beam offsets at the collision points are minimized during the leveling process. This paper will review sources and mitigation techniques for the orbit perturbation at the collision points during β^* leveling, and present results of experiments performed at the LHC to mitigate and compensate such offsets.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMW012

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

WEPOR005

Ground Motion Compensation using Feed-forward Control at ATF2

quadrupole, controls, extraction, feedback

2670

D.R. Bett, C. Charrondière, M. Patecki, J. Pfingstner, D. Schulte, R. Tomás
CERN, Geneva, Switzerland
A. Jeremie
IN2P3-LAPP, Annecy-le-Vieux, France
K. Kubo, S. Kuroda, T. Naito, T. Okugi, T. Tauchi, N. Terunuma
KEK, Ibaraki, Japan

Ground motion compensation using feed-forward control is a novel technique being developed to combat beam imperfections resulting from the vibration-induced misalignment of beamline components. The method is being evaluated experimentally at the KEK Accelerator Test Facility 2 (ATF2). It has already been demonstrated that the beam position correlates with the readings from a set of seismometers located along the beamline. To compensate for this contribution to the beam jitter, the fully operational system will use realtime measurement and processing in order to calculate and apply the feed-forward correction on a useful time scale. The progress towards a working system is presented in this paper.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOR005

Export •

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

WEPOR009

Intra-beam IP Feedback Studies for the 380 GeV CLIC Beam Delivery System

luminosity, feedback, kicker, simulation

2683

R.M. Bodenstein, P. Burrows, J. Snuverink
JAI, Oxford, United Kingdom
F. Plassard
CERN, Geneva, Switzerland

In its currently-envisaged initial stage, the Compact Linear Collider (CLIC) will collide beams with a 380 GeV center of mass energy. To maintain the luminosity within a few percent of the design value, beam stability at the interaction point (IP) must be controlled at the sub-nanometer level. To help achieve such control, use of an intra-pulse IP feedback system is planned. With CLIC's very short bunch spacing of 0.5 ns, and nominal pulse duration of 176 ns, this feedback system presents a significant technical challenge. Furthermore, as part of a study to optimize the design of the beam delivery system (BDS), several L* configurations have been studied. In this paper, we will review the IP feedback simulations for the 380 GeV machine for two L* configurations, and compare luminosity recovery performance with that of the original L* configuration in the 3 TeV machine.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOR009

Export •

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