IPAC2014 - List of Keywords (closed-orbit)

Paper	Title	Other Keywords	Page
MOPRO080	Fast Beam Orbit Monitoring System during Beam Abort at SPring-8 Storage Ring	operation, storage-ring, betatron, electronics	274
	T. Fujita, T. Masuda, S. Sasaki JASRI/SPring-8, Hyogo-ken, Japan H. Sumitomo SES, Hyogo-pref., Japan
	SPring-8 is a 3rd generation light source which has been operated stably. During user operation, an interlock system which turns off the RF acceleration signal if the beam orbit at insertion devices exceed a window is in operation. Beam abort events due to the interlock system have occurred as a rare event at SPring-8. Though in most cases we find trouble in accelerator devices as the source of the beam orbit shift, sometimes we cannot find any evidence after the beam abort. In order to identify the sources of such aborts, we have developed a system which observe beam orbit along the storage ring during beam abort. The system was realized by modification of the digital part of the existing COD measurement system. Every 1 ms, the system measures beam position at all BPMs with the position resolution of 1 micron or less. This system enabled us to identify the source when a beam abort due to an orbit shift with a time constant of longer than a few milliseconds. Furthermore, this system is applicable to survey sources of beam orbit fluctuations during stable operation. In this proceeding, we describe the system, beam orbit data during beam abort and source analysis.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-MOPRO080
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MOPRO086	On-line Beam Control with Ocelot at Siberia-2	controls, software, dipole, simulation	289
	S.I. Tomin, A.G. Valentinov NRC, Moscow, Russia
	Siberia-2 is a synchrotron light source with electron beam energy up to 2.5GeV, currently undergoing upgrade of controls hardware and software. Ocelot, an accelerator physics framework, was integrated with the new orbit correction system for high level beam control. We describe the steps taken for simulation studies of orbit correction strategies on a virtual machine model, integration of the software into the control system and experimental results.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-MOPRO086
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MOPRO095	Application Program for Automatically Getting the First Turn and Closed Orbit in TPS Commissioning	lattice, storage-ring, booster, quadrupole	310
	M.-S. Chiu, H.-P. Chang, P.J. Chou, F.H. Tseng NSRRC, Hsinchu, Taiwan
	Taiwan Photon Source (TPS) is a 3 GeV third generation electron synchrotron light source, consist of 5 major modules: LINAC, LTB transfer line, booster ring, BTS transfer line and storage ring. Its beam commissioning is scheduled in 2014. Getting the first turn and approaching the closed orbit is a crucial step for achieving stored beam in ring-based accelerator commissioning. In order to make first turn beam commissioning efficient, we develop a MATLAB-based application program based on AT and MML for automatic beam steering and closed orbit search. The algorithm and simulation results are presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-MOPRO095
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TUYB01	Vertical Orbit-excursion Fixed Field Alternating Gradient Accelerators (V-FFAGs) and 3D Cyclotrons	cyclotron, quadrupole, proton, acceleration	956
	S.J. Brooks BNL, Upton, Long Island, New York, USA
	FFAGs with vertical orbit excursion (VFFAGs) provide a promising alternative design for rings with fixed-field (e.g. superconducting) magnets. They have a vertical magnetic field component that increases with height in the vertical aperture, yielding a skew quadrupole focussing structure. Scaling type VFFAGs have fixed tunes and no intrinsic limitation on momentum range; they are also isochronous in the ultra-relativistic limit. Extending isochronism to lower velocities requires a slanted orbit excursion: a three-dimensional analogue of a spiral sector cyclotron from 40 to 1500MeV is developed, which is flat at low energies and acquires a slope as the protons become relativistic. This provides more stable tunes than a comparable planar cyclotron. Such machines are promising future candidates for nuclear transmutation using high average power CW beams at ~GeV energies.
	Slides TUYB01 [16.187 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUYB01
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TUPRO025	Initial Estimate of Fringe Field Effects in HL-LHC using Frequency Map Analysis	quadrupole, lattice, multipole, luminosity	1067
	S. Jones, D. Newton, A. Wolski The University of Liverpool, Liverpool, United Kingdom S. Jones, D. Newton, A. Wolski Cockcroft Institute, Warrington, Cheshire, United Kingdom
	Funding: Work supported by the Science and Technology Facilities Council, UK The planned High Luminosity upgrade to the LHC will require stronger focusing of the beam in the interaction regions. To achieve this, the inner triplet quadrupoles will be replaced with new magnets having larger gradient and aperture. In this new focusing regime the quadrupole fringe fields are expected to have a greater effect on the beam dynamics, due to their large aperture, as compared to the nominal LHC. In this preliminary study, simplified models are used in a tracking code to assess the impact of the fringe fields on the dynamics using frequency map analysis.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRO025
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TUPRO039	Optimizing Polarization with an Improved Integer Resonance Correction Scheme at ELSA	resonance, polarization, electron, quadrupole	1108
	J.F. Schmidt, O. Boldt, F. Frommberger, W. Hillert, J.-P. Thiry ELSA, Bonn, Germany
	Funding: DFG The Electron Stretcher Facility ELSA of Bonn University provides a polarized electron beam of up to 3.2 GeV. In the stretcher ring various depolarizing resonances are crossed during the fast energy ramp of 6 GeV/s. The high polarization degree of up to 70% can only be conserved by taking several appropriate countermeasures. Concerning integer resonances, additional harmonic horizontal fields are applied by orbit correction magnets around the ring to compensate the resonance driving fields. The correction field has to be adjusted by empirical optimization of polarization. Recent developments enhance this optimization process, especially at high energies: A new magnet system allows for higher correction amplitudes and shorter rising times. Furthermore, a modified correction scheme was implemented. It takes into account the additional fields of the quadrupole magnets, arising from the orbit response of the correction magnets.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRO039
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TUPRO040	High Bandwidth Closed Orbit Control for a Fast Ramping Electron Accelerator	resonance, acceleration, electron, polarization	1111
	J.-P. Thiry, A. Dieckmann, F. Frommberger, W. Hillert, J.F. Schmidt ELSA, Bonn, Germany
	ELSA is a fast ramping stretcher ring capable of acceleration and storage of polarized electrons with energies up to 3.2 GeV. To preserve the initial degree of polarization, the acceleration is performed by a fast energy ramp with a maximum ramping speed of 6 GeV/s. During acceleration especially the vertical orbit needs to be continuously corrected so that the vertical rms deviation does not exceed 50 μm at any time. In order to compensate the so called integer resonances, which occur at certain energies, the orbit correction system further needs to provide additional, empirically determined, harmonic field distributions. A successful application of these combined correction measures requires a considerably high bandwidth of up to some 100 Hz. In our contribution we will have a closer look at the performance and the acquired bandwidth of the correction system.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRO040
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TUPRO058	Lattice Correction Modeling for Fermilab IOTA Ring	lattice, optics, dipole, insertion	1165
	A.L. Romanov BINP SB RAS, Novosibirsk, Russia G.T. Kafka, S. Nagaitsev, A. Valishev Fermilab, Batavia, Illinois, USA
	The construction of the Integrable Optics Test Accelerator (IOTA) is underway at Fermilab. Among the main goals of the facility are the proof-of-principle experiments on nonlinear integrable optics and optical stochastic cooling. Both require outstanding quality of the linear lattice and closed orbit. Software was developed to thoroughly test the proposed lattice configurations for error correction performance. The presented analysis is based on a statistical approach on a number of error seeds, such as various alignment, calibration and field errors.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRO058
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TUPRI013	Dynamic Aperture Studies of the nuSTORM FFAG Ring	lattice, dynamic-aperture, factory, detector	1574
	R. Appleby, J.M. Garland, H.L. Owen, S.C. Tygier UMAN, Manchester, United Kingdom K.M. Hock Cockcroft Institute, Warrington, Cheshire, United Kingdom J.-B. Lagrange, J. Pasternak Imperial College of Science and Technology, Department of Physics, London, United Kingdom
	Funding: Research supported by STFC grant number ST/K002503/1 "Racetrack FFAGs for medical, PRISM and energy applications". FFAG rings with a racetrack configuration are very promising as their flexible design allow for dedicated spaces for injection/extraction, RF cavities etc. A racetrack FFAG is considered as an option for the nuSTORM facility, which aims to deliver neutrino beams produced from the decay of muons stored in a ring with long sections pointing towards detectors. In this paper we discuss the definition of dynamic aperture in these machines and use the PyZgoubi framework to compute the many turn motion in the nuSTORM ring. The roles of machine imperfections and symmetry are discussed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRI013
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WEPRO068	SPS Beam Steering for LHC Extraction	extraction, operation, quadrupole, simulation	2106
	E. Gianfelice-Wendt Fermilab, Batavia, Illinois, USA H. Bartosik, K. Cornelis, L.N. Drøsdal, B. Goddard, V. Kain, M. Meddahi, Y. Papaphilippou, J. Wenninger CERN, Geneva, Switzerland
	The CERN Super Proton Synchrotron accelerates beams for the Large Hadron Collider to 450 GeV. In addition it produces beams for fixed target facilities which adds complexity to the SPS operation. During the run 2012-2013 drifts of the extracted beam trajectories have been observed and lengthy optimizations in the transfer lines were performed to reduce particle losses in the LHC. The observed trajectory drifts are consistent with the measured SPS orbit drifts at extraction. While extensive studies are going on to understand, and possibly suppress, the source of such SPS orbit drifts the feasibility of an automatic beam steering towards a “golden” orbit at the extraction septa, by means of the interlocked correctors, is also being investigated. The challenges and constraints related to the implementation of such a correction in the SPS are described. Simulation results are presented and a possible operational steering strategy is proposed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEPRO068
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THPRO059	Simulation Study on Beam Loss in the Alpha Bucket Regime during SIS-100 Proton Operation	proton, extraction, simulation, synchrotron	3008
	S. Sorge GSI, Darmstadt, Germany
	Besides heavy ion operation, the heavy ion synchrotron SIS-100 will accelerate a single proton bunch of N=2*10¹³ particles up to the energy E=29 GeV. For the present standard scenario, optics settings have been developed which provide a transition energy according to gamma_tr=45.5 in order to avoid transition crossing during acceleration. At extraction energy the corresponding nonlinear momentum compaction and phase slip factors cause the formation of a so called alpha bucket. In this contribution we present the results of transverse beam loss tracking studies in the alpha bucket regime. The effects of momentum spread, magnet errors and residual closed orbit distortion are analyzed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRO059
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THPRO082	Observation of Coherent Instability in the CERN PS Booster	quadrupole, booster, acceleration, simulation	3076
	M. McAteer, C. Carli, V. Forte, G. Rumolo, R. Tomás CERN, Geneva, Switzerland
	Funding: This project has been supported by a Marie Curie Early Initial Training Network Fellowship of the European Community's Seventh Framework Programme, contract number (PITN-GA-2011-289485-OPAC). At high intensities and at a certain working point an instability develops in the CERN PS Booster, and large coherent transverse oscillations and beam loss occur. The coherent oscillations and beam loss can be effectively controlled with the transverse damper system, but the origin of the instability is not well-understood. Recent measurements with the PSB's new trajectory measurement system have provided some insight into the nature of this instability, and these observations are presented here.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRO082
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Paper

Title

Other Keywords

Page

MOPRO080

Fast Beam Orbit Monitoring System during Beam Abort at SPring-8 Storage Ring

operation, storage-ring, betatron, electronics

274

T. Fujita, T. Masuda, S. Sasaki
JASRI/SPring-8, Hyogo-ken, Japan
H. Sumitomo
SES, Hyogo-pref., Japan

SPring-8 is a 3rd generation light source which has been operated stably. During user operation, an interlock system which turns off the RF acceleration signal if the beam orbit at insertion devices exceed a window is in operation. Beam abort events due to the interlock system have occurred as a rare event at SPring-8. Though in most cases we find trouble in accelerator devices as the source of the beam orbit shift, sometimes we cannot find any evidence after the beam abort. In order to identify the sources of such aborts, we have developed a system which observe beam orbit along the storage ring during beam abort. The system was realized by modification of the digital part of the existing COD measurement system. Every 1 ms, the system measures beam position at all BPMs with the position resolution of 1 micron or less. This system enabled us to identify the source when a beam abort due to an orbit shift with a time constant of longer than a few milliseconds. Furthermore, this system is applicable to survey sources of beam orbit fluctuations during stable operation. In this proceeding, we describe the system, beam orbit data during beam abort and source analysis.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-MOPRO080

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MOPRO086

On-line Beam Control with Ocelot at Siberia-2

controls, software, dipole, simulation

289

S.I. Tomin, A.G. Valentinov
NRC, Moscow, Russia

Siberia-2 is a synchrotron light source with electron beam energy up to 2.5GeV, currently undergoing upgrade of controls hardware and software. Ocelot, an accelerator physics framework, was integrated with the new orbit correction system for high level beam control. We describe the steps taken for simulation studies of orbit correction strategies on a virtual machine model, integration of the software into the control system and experimental results.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-MOPRO086

Export •

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

MOPRO095

Application Program for Automatically Getting the First Turn and Closed Orbit in TPS Commissioning

lattice, storage-ring, booster, quadrupole

310

M.-S. Chiu, H.-P. Chang, P.J. Chou, F.H. Tseng
NSRRC, Hsinchu, Taiwan

Taiwan Photon Source (TPS) is a 3 GeV third generation electron synchrotron light source, consist of 5 major modules: LINAC, LTB transfer line, booster ring, BTS transfer line and storage ring. Its beam commissioning is scheduled in 2014. Getting the first turn and approaching the closed orbit is a crucial step for achieving stored beam in ring-based accelerator commissioning. In order to make first turn beam commissioning efficient, we develop a MATLAB-based application program based on AT and MML for automatic beam steering and closed orbit search. The algorithm and simulation results are presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-MOPRO095

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

TUYB01

Vertical Orbit-excursion Fixed Field Alternating Gradient Accelerators (V-FFAGs) and 3D Cyclotrons

cyclotron, quadrupole, proton, acceleration

956

S.J. Brooks
BNL, Upton, Long Island, New York, USA

FFAGs with vertical orbit excursion (VFFAGs) provide a promising alternative design for rings with fixed-field (e.g. superconducting) magnets. They have a vertical magnetic field component that increases with height in the vertical aperture, yielding a skew quadrupole focussing structure. Scaling type VFFAGs have fixed tunes and no intrinsic limitation on momentum range; they are also isochronous in the ultra-relativistic limit. Extending isochronism to lower velocities requires a slanted orbit excursion: a three-dimensional analogue of a spiral sector cyclotron from 40 to 1500MeV is developed, which is flat at low energies and acquires a slope as the protons become relativistic. This provides more stable tunes than a comparable planar cyclotron. Such machines are promising future candidates for nuclear transmutation using high average power CW beams at ~GeV energies.

Slides TUYB01 [16.187 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUYB01

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TUPRO025

Initial Estimate of Fringe Field Effects in HL-LHC using Frequency Map Analysis

quadrupole, lattice, multipole, luminosity

1067

S. Jones, D. Newton, A. Wolski
The University of Liverpool, Liverpool, United Kingdom
S. Jones, D. Newton, A. Wolski
Cockcroft Institute, Warrington, Cheshire, United Kingdom

Funding: Work supported by the Science and Technology Facilities Council, UK
The planned High Luminosity upgrade to the LHC will require stronger focusing of the beam in the interaction regions. To achieve this, the inner triplet quadrupoles will be replaced with new magnets having larger gradient and aperture. In this new focusing regime the quadrupole fringe fields are expected to have a greater effect on the beam dynamics, due to their large aperture, as compared to the nominal LHC. In this preliminary study, simplified models are used in a tracking code to assess the impact of the fringe fields on the dynamics using frequency map analysis.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRO025

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TUPRO039

Optimizing Polarization with an Improved Integer Resonance Correction Scheme at ELSA

resonance, polarization, electron, quadrupole

1108

J.F. Schmidt, O. Boldt, F. Frommberger, W. Hillert, J.-P. Thiry
ELSA, Bonn, Germany

Funding: DFG
The Electron Stretcher Facility ELSA of Bonn University provides a polarized electron beam of up to 3.2 GeV. In the stretcher ring various depolarizing resonances are crossed during the fast energy ramp of 6 GeV/s. The high polarization degree of up to 70% can only be conserved by taking several appropriate countermeasures. Concerning integer resonances, additional harmonic horizontal fields are applied by orbit correction magnets around the ring to compensate the resonance driving fields. The correction field has to be adjusted by empirical optimization of polarization. Recent developments enhance this optimization process, especially at high energies: A new magnet system allows for higher correction amplitudes and shorter rising times. Furthermore, a modified correction scheme was implemented. It takes into account the additional fields of the quadrupole magnets, arising from the orbit response of the correction magnets.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRO039

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

TUPRO040

High Bandwidth Closed Orbit Control for a Fast Ramping Electron Accelerator

resonance, acceleration, electron, polarization

1111

J.-P. Thiry, A. Dieckmann, F. Frommberger, W. Hillert, J.F. Schmidt
ELSA, Bonn, Germany

ELSA is a fast ramping stretcher ring capable of acceleration and storage of polarized electrons with energies up to 3.2 GeV. To preserve the initial degree of polarization, the acceleration is performed by a fast energy ramp with a maximum ramping speed of 6 GeV/s. During acceleration especially the vertical orbit needs to be continuously corrected so that the vertical rms deviation does not exceed 50 μm at any time. In order to compensate the so called integer resonances, which occur at certain energies, the orbit correction system further needs to provide additional, empirically determined, harmonic field distributions. A successful application of these combined correction measures requires a considerably high bandwidth of up to some 100 Hz. In our contribution we will have a closer look at the performance and the acquired bandwidth of the correction system.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRO040

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

TUPRO058

Lattice Correction Modeling for Fermilab IOTA Ring

lattice, optics, dipole, insertion

1165

A.L. Romanov
BINP SB RAS, Novosibirsk, Russia
G.T. Kafka, S. Nagaitsev, A. Valishev
Fermilab, Batavia, Illinois, USA

The construction of the Integrable Optics Test Accelerator (IOTA) is underway at Fermilab. Among the main goals of the facility are the proof-of-principle experiments on nonlinear integrable optics and optical stochastic cooling. Both require outstanding quality of the linear lattice and closed orbit. Software was developed to thoroughly test the proposed lattice configurations for error correction performance. The presented analysis is based on a statistical approach on a number of error seeds, such as various alignment, calibration and field errors.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRO058

Export •

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

TUPRI013

Dynamic Aperture Studies of the nuSTORM FFAG Ring

lattice, dynamic-aperture, factory, detector

1574

R. Appleby, J.M. Garland, H.L. Owen, S.C. Tygier
UMAN, Manchester, United Kingdom
K.M. Hock
Cockcroft Institute, Warrington, Cheshire, United Kingdom
J.-B. Lagrange, J. Pasternak
Imperial College of Science and Technology, Department of Physics, London, United Kingdom

Funding: Research supported by STFC grant number ST/K002503/1 "Racetrack FFAGs for medical, PRISM and energy applications".
FFAG rings with a racetrack configuration are very promising as their flexible design allow for dedicated spaces for injection/extraction, RF cavities etc. A racetrack FFAG is considered as an option for the nuSTORM facility, which aims to deliver neutrino beams produced from the decay of muons stored in a ring with long sections pointing towards detectors. In this paper we discuss the definition of dynamic aperture in these machines and use the PyZgoubi framework to compute the many turn motion in the nuSTORM ring. The roles of machine imperfections and symmetry are discussed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRI013

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

WEPRO068

SPS Beam Steering for LHC Extraction

extraction, operation, quadrupole, simulation

2106

E. Gianfelice-Wendt
Fermilab, Batavia, Illinois, USA
H. Bartosik, K. Cornelis, L.N. Drøsdal, B. Goddard, V. Kain, M. Meddahi, Y. Papaphilippou, J. Wenninger
CERN, Geneva, Switzerland

The CERN Super Proton Synchrotron accelerates beams for the Large Hadron Collider to 450 GeV. In addition it produces beams for fixed target facilities which adds complexity to the SPS operation. During the run 2012-2013 drifts of the extracted beam trajectories have been observed and lengthy optimizations in the transfer lines were performed to reduce particle losses in the LHC. The observed trajectory drifts are consistent with the measured SPS orbit drifts at extraction. While extensive studies are going on to understand, and possibly suppress, the source of such SPS orbit drifts the feasibility of an automatic beam steering towards a “golden” orbit at the extraction septa, by means of the interlocked correctors, is also being investigated. The challenges and constraints related to the implementation of such a correction in the SPS are described. Simulation results are presented and a possible operational steering strategy is proposed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEPRO068

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THPRO059

Simulation Study on Beam Loss in the Alpha Bucket Regime during SIS-100 Proton Operation

proton, extraction, simulation, synchrotron

3008

S. Sorge
GSI, Darmstadt, Germany

Besides heavy ion operation, the heavy ion synchrotron SIS-100 will accelerate a single proton bunch of N=2*10¹³ particles up to the energy E=29 GeV. For the present standard scenario, optics settings have been developed which provide a transition energy according to gamma_tr=45.5 in order to avoid transition crossing during acceleration. At extraction energy the corresponding nonlinear momentum compaction and phase slip factors cause the formation of a so called alpha bucket. In this contribution we present the results of transverse beam loss tracking studies in the alpha bucket regime. The effects of momentum spread, magnet errors and residual closed orbit distortion are analyzed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRO059

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THPRO082

Observation of Coherent Instability in the CERN PS Booster

quadrupole, booster, acceleration, simulation

3076

M. McAteer, C. Carli, V. Forte, G. Rumolo, R. Tomás
CERN, Geneva, Switzerland

Funding: This project has been supported by a Marie Curie Early Initial Training Network Fellowship of the European Community's Seventh Framework Programme, contract number (PITN-GA-2011-289485-OPAC).
At high intensities and at a certain working point an instability develops in the CERN PS Booster, and large coherent transverse oscillations and beam loss occur. The coherent oscillations and beam loss can be effectively controlled with the transverse damper system, but the origin of the instability is not well-understood. Recent measurements with the PSB's new trajectory measurement system have provided some insight into the nature of this instability, and these observations are presented here.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPRO082

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