IPAC2016 - List of Authors (Bertarelli, A.)

Paper	Title	Page
WEPMW030	Cleaning Performance of the Collimation System of the High Luminosity Large Hadron Collider	2494
	D. Mirarchi, A. Bertarelli, R. Bruce, F. Cerutti, P.D. Hermes, A. Lechner, A. Mereghetti, E. Quaranta, S. Redaelli CERN, Geneva, Switzerland R.B. Appleby UMAN, Manchester, United Kingdom H. Garcia Morales, R. Kwee-Hinzmann Royal Holloway, University of London, Surrey, United Kingdom
	Different upgrades of the LHC will be carried out in the framework of the High Luminosity project (HL-LHC), where the total stored energy in the machine will increase up to about 700 MJ. This unprecedented stored energy poses serious challenges for the collimation system, which was designed to handle safely up to about 360 MJ. In this paper the baseline collimation layout for HL-LHC is described, with main focus on upgrades related to the cleaning of halo and physics debris, and its expected performance is discussed. The main upgrade items include the presence of new collimators in the dispersion suppressor of the betatron cleaning insertion installed between two 11 T dipoles, and two additional collimators for an improved local protection of triplet magnets. Thus, optimized settings for the entire and upgraded collimation chain were conceived and are shown here together with the resulting cleaning performance. Moreover, the cleaning performance taking into account crab cavities it is also discussed.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMW030
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMW031	Towards Optimum Material Choices for the HL-LHC Collimator Upgrade	2498
	E. Quaranta, A. Bertarelli, N. Biancacci, R. Bruce, F. Carra, E. Métral, S. Redaelli, A. Rossi, B. Salvant CERN, Geneva, Switzerland F. Carra Politecnico di Torino, Torino, Italy
	The first years of operation at the LHC showed that collimator material-related concerns might limit the performance. In addition, the HL-LHC upgrade will bring the accelerator beyond the nominal performance through more intense and brighter proton beams. A new generation of collimators based on advanced materials is needed to match present and new requirements. After several years of R&D on collimator materials, studying the behaviour of novel composites with properties that address different limitations of the present collimation system, solutions have been found to fulfil various upgrade challenges. This paper describes the proposed staged approach to deploy new materials in the upgraded HL-LHC collimation system. Beam tests at the CERN HiRadMat facility were also performed to benchmark simulation methods and constitutive material models.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMW031
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMW032	Radiation-induced Effects on LHC Collimator Materials under Extreme Beam Conditions	2502
	E. Quaranta, A. Bertarelli, F. Carra, P.D. Hermes, S. Redaelli, A. Rossi CERN, Geneva, Switzerland K. Bunk Goethe Universität Frankfurt, Frankfurt am Main, Germany F. Carra Politecnico di Torino, Torino, Italy J. Guardia Valenzuela Universidad de Zaragoza, Zaragoza, Spain P.D. Hermes Westfaelische Wilhelms-Universität Muenster, Muenster, Germany C.L. Hubert, M. Tomut GSI, Darmstadt, Germany P. Nocera Università di Roma I La Sapienza, Roma, Italy C. Porth TU Darmstadt, Darmstadt, Germany N. Simos BNL, Upton, Long Island, New York, USA
	Over the last years, several samples of present and novel LHC collimator materials were irradiated under various beam conditions (using protons, fast neutrons, light and heavy ions at different energies and fluences) in different facilities around the world. This was achieved through an international collaboration including many companies and laboratories over the world. The main goal of the beam tests and the post-irradiation campaign is the definition of a threshold for radiation damage above which LHC collimators need to be replaced. In this paper, highlights of the measurements performed will be presented. First conclusions from the available data are also discussed.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMW032
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Cleaning Performance of the Collimation System of the High Luminosity Large Hadron Collider

2494

D. Mirarchi, A. Bertarelli, R. Bruce, F. Cerutti, P.D. Hermes, A. Lechner, A. Mereghetti, E. Quaranta, S. Redaelli
CERN, Geneva, Switzerland
R.B. Appleby
UMAN, Manchester, United Kingdom
H. Garcia Morales, R. Kwee-Hinzmann
Royal Holloway, University of London, Surrey, United Kingdom

Different upgrades of the LHC will be carried out in the framework of the High Luminosity project (HL-LHC), where the total stored energy in the machine will increase up to about 700 MJ. This unprecedented stored energy poses serious challenges for the collimation system, which was designed to handle safely up to about 360 MJ. In this paper the baseline collimation layout for HL-LHC is described, with main focus on upgrades related to the cleaning of halo and physics debris, and its expected performance is discussed. The main upgrade items include the presence of new collimators in the dispersion suppressor of the betatron cleaning insertion installed between two 11 T dipoles, and two additional collimators for an improved local protection of triplet magnets. Thus, optimized settings for the entire and upgraded collimation chain were conceived and are shown here together with the resulting cleaning performance. Moreover, the cleaning performance taking into account crab cavities it is also discussed.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMW030

Export •

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

WEPMW031

Towards Optimum Material Choices for the HL-LHC Collimator Upgrade

2498

E. Quaranta, A. Bertarelli, N. Biancacci, R. Bruce, F. Carra, E. Métral, S. Redaelli, A. Rossi, B. Salvant
CERN, Geneva, Switzerland
F. Carra
Politecnico di Torino, Torino, Italy

The first years of operation at the LHC showed that collimator material-related concerns might limit the performance. In addition, the HL-LHC upgrade will bring the accelerator beyond the nominal performance through more intense and brighter proton beams. A new generation of collimators based on advanced materials is needed to match present and new requirements. After several years of R&D on collimator materials, studying the behaviour of novel composites with properties that address different limitations of the present collimation system, solutions have been found to fulfil various upgrade challenges. This paper describes the proposed staged approach to deploy new materials in the upgraded HL-LHC collimation system. Beam tests at the CERN HiRadMat facility were also performed to benchmark simulation methods and constitutive material models.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMW031

Export •

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

WEPMW032

Radiation-induced Effects on LHC Collimator Materials under Extreme Beam Conditions

2502

E. Quaranta, A. Bertarelli, F. Carra, P.D. Hermes, S. Redaelli, A. Rossi
CERN, Geneva, Switzerland
K. Bunk
Goethe Universität Frankfurt, Frankfurt am Main, Germany
F. Carra
Politecnico di Torino, Torino, Italy
J. Guardia Valenzuela
Universidad de Zaragoza, Zaragoza, Spain
P.D. Hermes
Westfaelische Wilhelms-Universität Muenster, Muenster, Germany
C.L. Hubert, M. Tomut
GSI, Darmstadt, Germany
P. Nocera
Università di Roma I La Sapienza, Roma, Italy
C. Porth
TU Darmstadt, Darmstadt, Germany
N. Simos
BNL, Upton, Long Island, New York, USA

Over the last years, several samples of present and novel LHC collimator materials were irradiated under various beam conditions (using protons, fast neutrons, light and heavy ions at different energies and fluences) in different facilities around the world. This was achieved through an international collaboration including many companies and laboratories over the world. The main goal of the beam tests and the post-irradiation campaign is the definition of a threshold for radiation damage above which LHC collimators need to be replaced. In this paper, highlights of the measurements performed will be presented. First conclusions from the available data are also discussed.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMW032

Export •

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