IPAC2012 - List of Authors (Hernalsteens, C.)

Paper	Title	Page
MOPPD059	Proposal of a Dummy Septum to Mitigate Ring Irradiation for the CERN PS Multi-Turn Extraction	499
	M. Giovannozzi, H. Bartosik, D. Bodart, J. Borburgh, R.J. Brown, S. Damjanovic, S.S. Gilardoni, B. Goddard, C. Hernalsteens, M. Hourican, M. Widorski CERN, Geneva, Switzerland
	High activation of the magnetic extraction septum of the CERN PS machine was observed due to the losses of the continuous beam extracted via the Multi-Turn Extraction (MTE) method. The resulting activation is however incompatible with safe operation so a mitigation measure was required and found, namely the installation of a passive dummy septum to protect the actual one seems to provide the required reduction in activation in the extraction area. The shielded dummy septum is intended to absorb particles during the rise time of the MTE extraction kickers, avoiding the beam impact on the blade of the active magnetic extraction septum. The principle of the proposed modifications of the PS layout will be presented together with the studies aimed at finalising the new configuration.

MOPPD060	Modified Extraction Scheme for the CERN PS Multi-Turn Extraction	502
	M. Giovannozzi, S.S. Gilardoni, C. Hernalsteens, A. Lachaize, G. Métral CERN, Geneva, Switzerland
	High-activation of the extraction magnetic septum of the CERN PS machine was observed due to the losses of the continuous beam extracted via the Multi-Turn Extraction (MTE) method. A possible mitigation measure consists of using an existing electrostatic septum, located upstream of the extraction magnetic septum, to deflect the beam. This would highly decrease the beam losses, and hence the induced activation, during the rise time of the MTE kickers due to the reduced thickness of the electrostatic septum with respect to the magnetic one. The layout of this new extraction will be described in detail and the results of beam measurements presented.

TUPPC077	Numerical Study of Beam Trapping in Stable Islands for Simple 2D Models of Betatronic Motion	1350
	M. Giovannozzi, C. Hernalsteens CERN, Geneva, Switzerland
	An essential ingredient for the proposed Multi-Turn Extraction (MTE) at the CERN PS is the beam trapping in stable islands. The control of the trapping process is essential for the quality of the final beam in terms of intensity sharing and emittance. In this paper, the splitting process is studied quantitatively by means of numerical simulations performed on 2D model representing the horizontal non-linear betatronic motion. The results are reviewed and discussed in details.

TUPPC082	Non-linear Beam Dynamics Tests at the CERN PS in the Framework of the Multi-turn Extraction	1365
	M. Giovannozzi, G. Arduini, J.M. Belleman, S.S. Gilardoni, C. Hernalsteens, A. Lachaize, G. Métral, Y. Papaphilippou CERN, Geneva, Switzerland
	In the framework of the CERN PS Multi-Turn Extraction several campaigns of measurements probing the non-linear beam dynamics have been carried out. These measurements range from the measurement of non-linear chromaticity to phase space portraits, de-coherence and re-coherence measurements, secondary island tune etc. In this paper these measurements will be reviewed and the results presented and discussed in details.

Paper

Title

Page

Proposal of a Dummy Septum to Mitigate Ring Irradiation for the CERN PS Multi-Turn Extraction

499

M. Giovannozzi, H. Bartosik, D. Bodart, J. Borburgh, R.J. Brown, S. Damjanovic, S.S. Gilardoni, B. Goddard, C. Hernalsteens, M. Hourican, M. Widorski
CERN, Geneva, Switzerland

High activation of the magnetic extraction septum of the CERN PS machine was observed due to the losses of the continuous beam extracted via the Multi-Turn Extraction (MTE) method. The resulting activation is however incompatible with safe operation so a mitigation measure was required and found, namely the installation of a passive dummy septum to protect the actual one seems to provide the required reduction in activation in the extraction area. The shielded dummy septum is intended to absorb particles during the rise time of the MTE extraction kickers, avoiding the beam impact on the blade of the active magnetic extraction septum. The principle of the proposed modifications of the PS layout will be presented together with the studies aimed at finalising the new configuration.

MOPPD060

Modified Extraction Scheme for the CERN PS Multi-Turn Extraction

502

M. Giovannozzi, S.S. Gilardoni, C. Hernalsteens, A. Lachaize, G. Métral
CERN, Geneva, Switzerland

High-activation of the extraction magnetic septum of the CERN PS machine was observed due to the losses of the continuous beam extracted via the Multi-Turn Extraction (MTE) method. A possible mitigation measure consists of using an existing electrostatic septum, located upstream of the extraction magnetic septum, to deflect the beam. This would highly decrease the beam losses, and hence the induced activation, during the rise time of the MTE kickers due to the reduced thickness of the electrostatic septum with respect to the magnetic one. The layout of this new extraction will be described in detail and the results of beam measurements presented.

TUPPC077

Numerical Study of Beam Trapping in Stable Islands for Simple 2D Models of Betatronic Motion

1350

M. Giovannozzi, C. Hernalsteens
CERN, Geneva, Switzerland

An essential ingredient for the proposed Multi-Turn Extraction (MTE) at the CERN PS is the beam trapping in stable islands. The control of the trapping process is essential for the quality of the final beam in terms of intensity sharing and emittance. In this paper, the splitting process is studied quantitatively by means of numerical simulations performed on 2D model representing the horizontal non-linear betatronic motion. The results are reviewed and discussed in details.

TUPPC082

Non-linear Beam Dynamics Tests at the CERN PS in the Framework of the Multi-turn Extraction

1365

M. Giovannozzi, G. Arduini, J.M. Belleman, S.S. Gilardoni, C. Hernalsteens, A. Lachaize, G. Métral, Y. Papaphilippou
CERN, Geneva, Switzerland

In the framework of the CERN PS Multi-Turn Extraction several campaigns of measurements probing the non-linear beam dynamics have been carried out. These measurements range from the measurement of non-linear chromaticity to phase space portraits, de-coherence and re-coherence measurements, secondary island tune etc. In this paper these measurements will be reviewed and the results presented and discussed in details.