IPAC2011 - List of Authors (Weisz, S.)

Paper

Title

Page

The Linac4 Project at CERN

900

M. Vretenar, L. Arnaudon, P. Baudrenghien, C. Bertone, Y. Body, J.C. Broere, O. Brunner, M.C.L. Buzio, C. Carli, F. Caspers, J.-P. Corso, J. Coupard, A. Dallocchio, N. Dos Santos, R. Garoby, F. Gerigk, L. Hammouti, K. Hanke, M.A. Jones, I. Kozsar, J.-B. Lallement, J. Lettry, A.M. Lombardi, L.A. Lopez Hernandez, C. Maglioni, S.J. Mathot, S. Maury, B. Mikulec, D. Nisbet, C. Noels, M.M. Paoluzzi, B. Puccio, U. Raich, S. Ramberger, C. Rossi, N. Schwerg, R. Scrivens, G. Vandoni, J. Vollaire, S. Weisz, Th. Zickler
CERN, Geneva, Switzerland

As the first step of a long-term programme aiming at an increase in the LHC luminosity, CERN is building a new 160 MeV H⁻ linear accelerator, Linac4, to replace the ageing 50 MeV Linac2 as injector to the Proton-Synchrotron Booster (PSB). Linac4 is an 86-m long normal-conducting linac made of an H⁻ source, a Radio Frequency Quadrupole (RFQ), a chopping line and a sequence of three accelerating structures: a Drift-Tube Linac (DTL), a Cell-Coupled DTL (CCDTL) and a Pi-Mode Structure (PIMS). The civil engineering has been recently completed, and construction of the main accelerator components has started with the support of a network of international collaborations. The low-energy section up to 3 MeV including a 3-m long 352 MHz RFQ entirely built at CERN is in the final construction phase and is being installed on a dedicated test stand. The present schedule foresees beam commissioning of the accelerator in the new tunnel in 2013/14; the moment of connection of the new linac to the CERN accelerator chain will depend on the LHC schedule for long shut-downs.

Slides TUOAA03 [10.347 MB]

THPS055

Controlling Beamloss at Injection into the LHC

3553

B. Goddard, F. Alessio, W. Bartmann, P. Baudrenghien, V. Boccone, C. Bracco, M. Brugger, K. Cornelis, B. Dehning, A. Di Mauro, L.N. Drosdal, E.B. Holzer, W. Höfle, R. Jacobsson, V. Kain, M. Meddahi, V. Mertens, A. Nordt, J.A. Uythoven, D. Valuch, S. Weisz, E.N. del Busto
CERN, Geneva, Switzerland
R. Appleby
UMAN, Manchester, United Kingdom

Losses at injection into the superconducting LHC can adversely affect the machine performance in several important ways. The high injected beam intensity and energy mean that precautions must be taken against damage and quenches, including collimators placed close to the beam in the injection regions. Clean injection is essential, to avoid spurious signals on the sensitive beam loss monitoring system which will trigger beam dumps. In addition, the use of the two injection insertions to house downstream high energy physics experiments brings constraints on permitted beam loss levels. In this paper the sources of injection beam loss are discussed together with the contributing factors and various issues experienced in the first full year of LHC operation. Simulations are compared with measurement, and the implemented and planned mitigation measures and diagnostic improvements are described. An outlook for future LHC operation is given.

Paper	Title	Page
TUOAA03	The Linac4 Project at CERN	900
	M. Vretenar, L. Arnaudon, P. Baudrenghien, C. Bertone, Y. Body, J.C. Broere, O. Brunner, M.C.L. Buzio, C. Carli, F. Caspers, J.-P. Corso, J. Coupard, A. Dallocchio, N. Dos Santos, R. Garoby, F. Gerigk, L. Hammouti, K. Hanke, M.A. Jones, I. Kozsar, J.-B. Lallement, J. Lettry, A.M. Lombardi, L.A. Lopez Hernandez, C. Maglioni, S.J. Mathot, S. Maury, B. Mikulec, D. Nisbet, C. Noels, M.M. Paoluzzi, B. Puccio, U. Raich, S. Ramberger, C. Rossi, N. Schwerg, R. Scrivens, G. Vandoni, J. Vollaire, S. Weisz, Th. Zickler CERN, Geneva, Switzerland
	As the first step of a long-term programme aiming at an increase in the LHC luminosity, CERN is building a new 160 MeV H⁻ linear accelerator, Linac4, to replace the ageing 50 MeV Linac2 as injector to the Proton-Synchrotron Booster (PSB). Linac4 is an 86-m long normal-conducting linac made of an H⁻ source, a Radio Frequency Quadrupole (RFQ), a chopping line and a sequence of three accelerating structures: a Drift-Tube Linac (DTL), a Cell-Coupled DTL (CCDTL) and a Pi-Mode Structure (PIMS). The civil engineering has been recently completed, and construction of the main accelerator components has started with the support of a network of international collaborations. The low-energy section up to 3 MeV including a 3-m long 352 MHz RFQ entirely built at CERN is in the final construction phase and is being installed on a dedicated test stand. The present schedule foresees beam commissioning of the accelerator in the new tunnel in 2013/14; the moment of connection of the new linac to the CERN accelerator chain will depend on the LHC schedule for long shut-downs.
	Slides TUOAA03 [10.347 MB]

THPS055	Controlling Beamloss at Injection into the LHC	3553
	B. Goddard, F. Alessio, W. Bartmann, P. Baudrenghien, V. Boccone, C. Bracco, M. Brugger, K. Cornelis, B. Dehning, A. Di Mauro, L.N. Drosdal, E.B. Holzer, W. Höfle, R. Jacobsson, V. Kain, M. Meddahi, V. Mertens, A. Nordt, J.A. Uythoven, D. Valuch, S. Weisz, E.N. del Busto CERN, Geneva, Switzerland R. Appleby UMAN, Manchester, United Kingdom
	Losses at injection into the superconducting LHC can adversely affect the machine performance in several important ways. The high injected beam intensity and energy mean that precautions must be taken against damage and quenches, including collimators placed close to the beam in the injection regions. Clean injection is essential, to avoid spurious signals on the sensitive beam loss monitoring system which will trigger beam dumps. In addition, the use of the two injection insertions to house downstream high energy physics experiments brings constraints on permitted beam loss levels. In this paper the sources of injection beam loss are discussed together with the contributing factors and various issues experienced in the first full year of LHC operation. Simulations are compared with measurement, and the implemented and planned mitigation measures and diagnostic improvements are described. An outlook for future LHC operation is given.