IPAC2011 - List of Authors (Steerenberg, R.R.)

Paper	Title	Page
MOPS014	Tune and Space Charge Studies for High-brightness and High-intensity Beams at CERN PS	625
	S.S. Gilardoni, S. Aumon, J. Brenas, P. Freyermuth, A. Huschauer, R. Maillet, E. Matli, R.R. Steerenberg, B. Vandorpe CERN, Geneva, Switzerland E. Benedetto National Technical University of Athens, Zografou, Greece
	The current 1.4 GeV CERN PS injection energy limits the maximum intensity required by the future High-Luminosity LHC. The bare-machine large chromaticity combined with the non-linear space charge forces make high-brightness and high-intensity beams crossing betatron resonances along the injection flat bottom, inducing transverse emittance blow-up and beam losses. A scan of the working point plane {Qx,Qy} was done in order to identify beam destructive resonances, in the framework of a possible 2 GeV injection energy upgrade which would reduce the space charge effect on the tune. Experiments were carried out in order to review the maximum space charge tune shift for which no transverse emittance blow-up is observed. The results of measurements and simulations will be presented in this paper.

MOPS009	Probing Intensity Limits of LHC-type Bunches in the CERN SPS with Nominal Optics	610
	B. Salvant, G. Adrian, D.J. Allen, O. Andujar, T. Argyropoulos, J. Axensalva, J. Baldy, H. Bartosik, S. Cettour Cave, F. Chapuis, J.F. Comblin, K. Cornelis, D.G. Cotte, K. Cunnington, H. Damerau, M. Delrieux, J.L. Duran-Lopez, A. Findlay, J. Fleuret, F. Follin, P. Freyermuth, H. Genoud, S.S. Gilardoni, A. Guerrero, S. Hancock, K. Hanke, O. Hans, R. Hazelaar, W. Höfle, L.K. Jensen, J. Kuczerowski, Y. Le Borgne, R. Maillet, D. Manglunki, S. Massot, E. Matli, G. Metral, B. Mikulec, E. Métral, J.-M. Nonglaton, E. Ovalle, L. Pereira, F.C. Peters, A. Rey, J.P. Ridewood, G. Rumolo, J.L. Sanchez Alvarez, E.N. Shaposhnikova, R.R. Steerenberg, R.J. Steinhagen, J. Tan, B. Vandorpe, E. Veyrunes CERN, Geneva, Switzerland
	Some of the upgrade scenarios of the high-luminosity LHC require large intensity per bunch from the injector chain. Single bunch beams with intensities of up to 3.5 to 4·10¹¹ p/b and nominal emittances were successfully produced in the PS Complex and delivered to the SPS in 2010. This contribution presents results of studies with this new intense beam in the SPS to probe single bunch intensity limitations with nominal gamma transition. In particular, the vertical Transverse Mode Coupling Instability (TMCI) threshold with low chromaticity was observed at 1.6·10¹¹ p/b for single nominal LHC bunches in the SPS. With increased vertical chromaticity, larger intensities could be injected, stored along the flat bottom and accelerated up to 450 GeV/c. However, significant losses and/or transverse emittance blow up were then observed. Longitudinal and transverse optimization efforts in the PSB, PS and SPS were put in place to minimize this beam degradation and succeeded to obtain single 2.3·10¹¹ p/b LHC type bunches with satisfying parameters at extraction of the SPS.

WEPS018	The Proposed CERN Proton-Synchrotron Upgrade Program	2520
	S.S. Gilardoni, S. Bart Pedersen, W. Bartmann, S. Bartolome, O.E. Berrig, C. Bertone, A. Blas, D. Bodart, J. Borburgh, R.J. Brown, A.C. Butterworth, M.C.L. Buzio, C. Carli, P. Chiggiato, H. Damerau, T. Dobers, R. Folch, R. Garoby, B. Goddard, M. Gourber-Pace, S. Hancock, M. Hourican, P. Le Roux, L.A. Lopez Hernandez, A. Masi, G. Metral, Y. Muttoni, E. Métral, M. Nonis, J. Pierlot, S. Pittet, C. Rossi, I. Ruehl, G. Rumolo, L. Sermeus, R.R. Steerenberg, M. Widorski CERN, Geneva, Switzerland
	In the framework of the High-Luminosity LHC project, the CERN Proton Synchrotron would require a major upgrade to match the future beam parameters requested as pre-injector of the collider. The different beam dynamics issues, from space-charge limitations to longitudinal instabilities are discussed, as well as the proposed technical solutions to overcome them, covering the increase of the injection energy to RF related improvements.

WEPS019	Study of a Rapid Cycling Synchrotron to Replace the CERN PS Booster	2523
	K. Hanke, O. Aberle, M. E. Angoletta, B. Balhan, W. Bartmann, M. Benedikt, J. Borburgh, D. Bozzini, C. Carli, P. Dahlen, T. Dobers, M. Fitterer, R. Garoby, S.S. Gilardoni, B. Goddard, J. Hansen, T. Hermanns, M. Hourican, S. Jensen, A. Kosmicki, L.A. Lopez Hernandez, M. Meddahi, B. Mikulec, A. Newborough, M. Nonis, S. Olek, M.M. Paoluzzi, S. Pittet, B. Puccio, V. Raginel, I. Ruehl, H.O. Schönauer, L. Sermeus, R.R. Steerenberg, J. Tan, J. Tückmantel, M. Vretenar, M. Widorski CERN, Geneva, Switzerland
	CERN’s proton injector chain is undergoing a massive consolidation and upgrade program in order to deliver beams meeting the needs of the LHC Luminosity Upgrade. As an alternative to the upgrade of the existing Proton Synchrotron Booster (PSB), the construction of a Rapid Cycling Synchrotron (RCS) has been studied. This machine would replace the PSB and deliver beams to the LHC as well as to CERN’s rich fixed-target physics program. This paper summarizes the outcome of the feasibility study along with a tentative RCS design.

THPS049	Feasibility Study of a CERN PS Injection at 2 GeV	3535
	J. Borburgh, S. Aumon, W. Bartmann, S.S. Gilardoni, B. Goddard, L. Sermeus, R.R. Steerenberg CERN, Geneva, Switzerland
	In the framework of the potential CERN PS Booster (PSB) energy upgrade, a study was initiated to look into the possibilities and constraints to inject protons into the PS at kinetic energies up to 2 GeV, for LHC type beams and other (high intensity) beams. This paper highlights the identified bottlenecks and potential solutions and addresses the resulting requirements for the hardware in the transfer line and injection region of the PS. In conjunction with the proposed upgrade of the PSB-PS transfer line hardware the optics can be changed for different cycles. Optics solutions optimized for the different requirements of LHC type and other beams are presented.

Paper

Title

Page

Tune and Space Charge Studies for High-brightness and High-intensity Beams at CERN PS

625

S.S. Gilardoni, S. Aumon, J. Brenas, P. Freyermuth, A. Huschauer, R. Maillet, E. Matli, R.R. Steerenberg, B. Vandorpe
CERN, Geneva, Switzerland
E. Benedetto
National Technical University of Athens, Zografou, Greece

The current 1.4 GeV CERN PS injection energy limits the maximum intensity required by the future High-Luminosity LHC. The bare-machine large chromaticity combined with the non-linear space charge forces make high-brightness and high-intensity beams crossing betatron resonances along the injection flat bottom, inducing transverse emittance blow-up and beam losses. A scan of the working point plane {Qx,Qy} was done in order to identify beam destructive resonances, in the framework of a possible 2 GeV injection energy upgrade which would reduce the space charge effect on the tune. Experiments were carried out in order to review the maximum space charge tune shift for which no transverse emittance blow-up is observed. The results of measurements and simulations will be presented in this paper.

MOPS009

Probing Intensity Limits of LHC-type Bunches in the CERN SPS with Nominal Optics

610

B. Salvant, G. Adrian, D.J. Allen, O. Andujar, T. Argyropoulos, J. Axensalva, J. Baldy, H. Bartosik, S. Cettour Cave, F. Chapuis, J.F. Comblin, K. Cornelis, D.G. Cotte, K. Cunnington, H. Damerau, M. Delrieux, J.L. Duran-Lopez, A. Findlay, J. Fleuret, F. Follin, P. Freyermuth, H. Genoud, S.S. Gilardoni, A. Guerrero, S. Hancock, K. Hanke, O. Hans, R. Hazelaar, W. Höfle, L.K. Jensen, J. Kuczerowski, Y. Le Borgne, R. Maillet, D. Manglunki, S. Massot, E. Matli, G. Metral, B. Mikulec, E. Métral, J.-M. Nonglaton, E. Ovalle, L. Pereira, F.C. Peters, A. Rey, J.P. Ridewood, G. Rumolo, J.L. Sanchez Alvarez, E.N. Shaposhnikova, R.R. Steerenberg, R.J. Steinhagen, J. Tan, B. Vandorpe, E. Veyrunes
CERN, Geneva, Switzerland

Some of the upgrade scenarios of the high-luminosity LHC require large intensity per bunch from the injector chain. Single bunch beams with intensities of up to 3.5 to 4·10¹¹ p/b and nominal emittances were successfully produced in the PS Complex and delivered to the SPS in 2010. This contribution presents results of studies with this new intense beam in the SPS to probe single bunch intensity limitations with nominal gamma transition. In particular, the vertical Transverse Mode Coupling Instability (TMCI) threshold with low chromaticity was observed at 1.6·10¹¹ p/b for single nominal LHC bunches in the SPS. With increased vertical chromaticity, larger intensities could be injected, stored along the flat bottom and accelerated up to 450 GeV/c. However, significant losses and/or transverse emittance blow up were then observed. Longitudinal and transverse optimization efforts in the PSB, PS and SPS were put in place to minimize this beam degradation and succeeded to obtain single 2.3·10¹¹ p/b LHC type bunches with satisfying parameters at extraction of the SPS.

WEPS018

The Proposed CERN Proton-Synchrotron Upgrade Program

2520

S.S. Gilardoni, S. Bart Pedersen, W. Bartmann, S. Bartolome, O.E. Berrig, C. Bertone, A. Blas, D. Bodart, J. Borburgh, R.J. Brown, A.C. Butterworth, M.C.L. Buzio, C. Carli, P. Chiggiato, H. Damerau, T. Dobers, R. Folch, R. Garoby, B. Goddard, M. Gourber-Pace, S. Hancock, M. Hourican, P. Le Roux, L.A. Lopez Hernandez, A. Masi, G. Metral, Y. Muttoni, E. Métral, M. Nonis, J. Pierlot, S. Pittet, C. Rossi, I. Ruehl, G. Rumolo, L. Sermeus, R.R. Steerenberg, M. Widorski
CERN, Geneva, Switzerland

In the framework of the High-Luminosity LHC project, the CERN Proton Synchrotron would require a major upgrade to match the future beam parameters requested as pre-injector of the collider. The different beam dynamics issues, from space-charge limitations to longitudinal instabilities are discussed, as well as the proposed technical solutions to overcome them, covering the increase of the injection energy to RF related improvements.

WEPS019

Study of a Rapid Cycling Synchrotron to Replace the CERN PS Booster

2523

K. Hanke, O. Aberle, M. E. Angoletta, B. Balhan, W. Bartmann, M. Benedikt, J. Borburgh, D. Bozzini, C. Carli, P. Dahlen, T. Dobers, M. Fitterer, R. Garoby, S.S. Gilardoni, B. Goddard, J. Hansen, T. Hermanns, M. Hourican, S. Jensen, A. Kosmicki, L.A. Lopez Hernandez, M. Meddahi, B. Mikulec, A. Newborough, M. Nonis, S. Olek, M.M. Paoluzzi, S. Pittet, B. Puccio, V. Raginel, I. Ruehl, H.O. Schönauer, L. Sermeus, R.R. Steerenberg, J. Tan, J. Tückmantel, M. Vretenar, M. Widorski
CERN, Geneva, Switzerland

CERN’s proton injector chain is undergoing a massive consolidation and upgrade program in order to deliver beams meeting the needs of the LHC Luminosity Upgrade. As an alternative to the upgrade of the existing Proton Synchrotron Booster (PSB), the construction of a Rapid Cycling Synchrotron (RCS) has been studied. This machine would replace the PSB and deliver beams to the LHC as well as to CERN’s rich fixed-target physics program. This paper summarizes the outcome of the feasibility study along with a tentative RCS design.

THPS049

Feasibility Study of a CERN PS Injection at 2 GeV

3535

J. Borburgh, S. Aumon, W. Bartmann, S.S. Gilardoni, B. Goddard, L. Sermeus, R.R. Steerenberg
CERN, Geneva, Switzerland

In the framework of the potential CERN PS Booster (PSB) energy upgrade, a study was initiated to look into the possibilities and constraints to inject protons into the PS at kinetic energies up to 2 GeV, for LHC type beams and other (high intensity) beams. This paper highlights the identified bottlenecks and potential solutions and addresses the resulting requirements for the hardware in the transfer line and injection region of the PS. In conjunction with the proposed upgrade of the PSB-PS transfer line hardware the optics can be changed for different cycles. Optics solutions optimized for the different requirements of LHC type and other beams are presented.