IPAC2019 - List of Keywords (ground-motion)

Paper	Title	Other Keywords	Page
MOPMP017	Beam Orbit Correction in the CLIC Main Linac Using a Small Subset of Correctors	linac, emittance, quadrupole, collider	461
	N. Blaskovic Kraljevic, D. Schulte CERN, Meyrin, Switzerland
	Beam orbit correction in future linear colliders, such as the Compact Linear Collider (CLIC), is essential to mitigate the effect of accelerator element misalignment due to ground motion. The correction is performed using correctors distributed along the accelerator, based on the beam position monitor (BPM) readout from the preceding bunch train, with a train repetition frequency of 50 Hz. This paper presents the use of the MICADO algorithm* to select a subset of N ~ 10 correctors (from a total of 576) to be used for orbit correction in the designed 380 GeV centre-of-mass energy first-stage of CLIC. The optimisation of the number N of correctors, the algorithm’s gain and the corrector step size is described, and the impact of a number of BPMs and correctors becoming unavailable is addressed. The application of a MICADO algorithm to perform dispersion free steering, by reducing the beam orbit difference between two beams with different energies, is discussed. * B. Autin & Y. Marti, "Closed orbit correction of A.G. machines using a small number of magnets", CERN-ISR-MA/73-17, 1973.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-MOPMP017
About •	paper received ※ 13 May 2019 paper accepted ※ 20 May 2019 issue date ※ 21 June 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPRB116	Effect of Ground Motion Introduced by HL-LHC CE Work on LHC Beam Operation	luminosity, operation, civil-engineering, GUI	4092
	M. Schaumann, D. Gamba, M. Guinchard, L. Scislo, J. Wenninger CERN, Geneva, Switzerland
	Funding: Research supported by the HL-LHC project The official groundbreaking of the civil engineering (CE) work for the high luminosity upgrade of the LHC started on 15 June 2018 parallel to LHC beam operation. Compactor work and shaft excavation around the two low beta experiments, ATLAS and CMS, were expected to induce vibrations to the accelerator magnets and cause orbit disturbance, beam loss and potentially premature beam dumps. Ground motion sensors were installed on the surface and close to the triplets, where the CE works were expected to have the largest impact on the beams. This paper discusses the observations made on the LHC beams that could be correlated to CE work.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-THPRB116
About •	paper received ※ 13 May 2019 paper accepted ※ 22 May 2019 issue date ※ 21 June 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Other Keywords

Page

MOPMP017

Beam Orbit Correction in the CLIC Main Linac Using a Small Subset of Correctors

linac, emittance, quadrupole, collider

461

N. Blaskovic Kraljevic, D. Schulte
CERN, Meyrin, Switzerland

Beam orbit correction in future linear colliders, such as the Compact Linear Collider (CLIC), is essential to mitigate the effect of accelerator element misalignment due to ground motion. The correction is performed using correctors distributed along the accelerator, based on the beam position monitor (BPM) readout from the preceding bunch train, with a train repetition frequency of 50 Hz. This paper presents the use of the MICADO algorithm* to select a subset of N ~ 10 correctors (from a total of 576) to be used for orbit correction in the designed 380 GeV centre-of-mass energy first-stage of CLIC. The optimisation of the number N of correctors, the algorithm’s gain and the corrector step size is described, and the impact of a number of BPMs and correctors becoming unavailable is addressed. The application of a MICADO algorithm to perform dispersion free steering, by reducing the beam orbit difference between two beams with different energies, is discussed.
* B. Autin & Y. Marti, "Closed orbit correction of A.G. machines using a small number of magnets", CERN-ISR-MA/73-17, 1973.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-MOPMP017

About •

paper received ※ 13 May 2019 paper accepted ※ 20 May 2019 issue date ※ 21 June 2019

Export •

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

THPRB116

Effect of Ground Motion Introduced by HL-LHC CE Work on LHC Beam Operation

luminosity, operation, civil-engineering, GUI

4092

M. Schaumann, D. Gamba, M. Guinchard, L. Scislo, J. Wenninger
CERN, Geneva, Switzerland

Funding: Research supported by the HL-LHC project
The official groundbreaking of the civil engineering (CE) work for the high luminosity upgrade of the LHC started on 15 June 2018 parallel to LHC beam operation. Compactor work and shaft excavation around the two low beta experiments, ATLAS and CMS, were expected to induce vibrations to the accelerator magnets and cause orbit disturbance, beam loss and potentially premature beam dumps. Ground motion sensors were installed on the surface and close to the triplets, where the CE works were expected to have the largest impact on the beams. This paper discusses the observations made on the LHC beams that could be correlated to CE work.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-THPRB116

About •

paper received ※ 13 May 2019 paper accepted ※ 22 May 2019 issue date ※ 21 June 2019

Export •

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