IPAC2015 - List of Authors (Quaranta, E.)

Paper	Title	Page
TUPTY024	Updated Simulation Studies of Damage Limit of LHC Tertiary Collimators	2053
	E. Quaranta, A. Bertarelli, R. Bruce, F. Carra, F. Cerutti, P. Gradassi, A. Lechner, S. Redaelli, E. Skordis CERN, Geneva, Switzerland
	The tertiary collimators (TCTs) in the LHC, installed in front of the experiments, in standard operation intercept fractions of 10³ halo particles. However, they risk to be hit by high-intensity primary beams in case of asynchronous beam dump. TCT damage thresholds were initially inferred from results of destructive tests on a TCT jaw, supported by numerical simulations, assuming simplified impact scenarios with one single bunch hitting the jaw with a given impact parameter. In this paper, more realistic failure conditions, including a train of bunches and taking into account the full collimation hierarchy, are used to derive updated damage limits. The results are used to update the margins in the collimation hierarchy and could thus potentially have an influence on the LHC performance.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-TUPTY024
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TUPTY028	Collimator Layouts for HL-LHC in the Experimental Insertions	2064
	R. Bruce, F. Cerutti, L.S. Esposito, J.M. Jowett, A. Lechner, E. Quaranta, S. Redaelli, M. Schaumann, E. Skordis, G.E. Steele CERN, Geneva, Switzerland H. Garcia Morales, R. Kwee-Hinzmann JAI, Egham, Surrey, United Kingdom
	This paper presents the layout of collimators for HL-LHC in the experimental insertions. On the incoming beam, we propose to install additional tertiary collimators to protect potential new aperture bottlenecks in cells 4 and 5, which in addition reduce the experimental background. For the outgoing beam, the layout of the present LHC with three physics debris absorbers gives sufficient protection for high-luminosity proton operation. However, collisional processes for heavy ions cause localized beam losses with the potential to quench magnets. To alleviate these losses, an installation of dispersion suppressor collimators is proposed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-TUPTY028
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TUPTY029	Collimation Cleaning at the LHC with Advanced Secondary Collimator Materials	2068
	E. Quaranta, R. Bruce, A. Mereghetti, S. Redaelli, A. Rossi CERN, Geneva, Switzerland
	The LHC collimation system must ensure efficient beam halo cleaning in all machine conditions. The first run in 2010-2013 showed that the LHC performance may be limited by collimator material-related concerns, such as the contribution from the present carbon-based secondary collimators to the machine impedance and, consequently, to the beam instability. Novel materials based on composites are currently under development for the next generation of LHC collimators to address these limitations. Particle tracking simulations of collimation efficiency were performed using the Sixtrack code and a material database updated to model these composites. In this paper, the simulation results will be presented with the aim of studying the effect of the advanced collimators on the LHC beam cleaning.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-TUPTY029
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Updated Simulation Studies of Damage Limit of LHC Tertiary Collimators

2053

E. Quaranta, A. Bertarelli, R. Bruce, F. Carra, F. Cerutti, P. Gradassi, A. Lechner, S. Redaelli, E. Skordis
CERN, Geneva, Switzerland

The tertiary collimators (TCTs) in the LHC, installed in front of the experiments, in standard operation intercept fractions of 10³ halo particles. However, they risk to be hit by high-intensity primary beams in case of asynchronous beam dump. TCT damage thresholds were initially inferred from results of destructive tests on a TCT jaw, supported by numerical simulations, assuming simplified impact scenarios with one single bunch hitting the jaw with a given impact parameter. In this paper, more realistic failure conditions, including a train of bunches and taking into account the full collimation hierarchy, are used to derive updated damage limits. The results are used to update the margins in the collimation hierarchy and could thus potentially have an influence on the LHC performance.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-TUPTY024

Export •

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

TUPTY028

Collimator Layouts for HL-LHC in the Experimental Insertions

2064

R. Bruce, F. Cerutti, L.S. Esposito, J.M. Jowett, A. Lechner, E. Quaranta, S. Redaelli, M. Schaumann, E. Skordis, G.E. Steele
CERN, Geneva, Switzerland
H. Garcia Morales, R. Kwee-Hinzmann
JAI, Egham, Surrey, United Kingdom

This paper presents the layout of collimators for HL-LHC in the experimental insertions. On the incoming beam, we propose to install additional tertiary collimators to protect potential new aperture bottlenecks in cells 4 and 5, which in addition reduce the experimental background. For the outgoing beam, the layout of the present LHC with three physics debris absorbers gives sufficient protection for high-luminosity proton operation. However, collisional processes for heavy ions cause localized beam losses with the potential to quench magnets. To alleviate these losses, an installation of dispersion suppressor collimators is proposed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-TUPTY028

Export •

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

TUPTY029

Collimation Cleaning at the LHC with Advanced Secondary Collimator Materials

2068

E. Quaranta, R. Bruce, A. Mereghetti, S. Redaelli, A. Rossi
CERN, Geneva, Switzerland

The LHC collimation system must ensure efficient beam halo cleaning in all machine conditions. The first run in 2010-2013 showed that the LHC performance may be limited by collimator material-related concerns, such as the contribution from the present carbon-based secondary collimators to the machine impedance and, consequently, to the beam instability. Novel materials based on composites are currently under development for the next generation of LHC collimators to address these limitations. Particle tracking simulations of collimation efficiency were performed using the Sixtrack code and a material database updated to model these composites. In this paper, the simulation results will be presented with the aim of studying the effect of the advanced collimators on the LHC beam cleaning.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-TUPTY029

Export •

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