IPAC2017 - Classification: 05 Beam Dynamics and Electromagnetic Fields / D07 High Intensity Circular Machines

Paper	Title	Page
WEXB1	Studies and Observations of Beam Dynamics Near a Sum Resonance	2503
	G. Franchetti GSI, Darmstadt, Germany S.S. Gilardoni, A. Huschauer, F. Schmidt, R. Wasef CERN, Geneva, Switzerland
	The effect of space charge on bunches stored for long term in a can be severe for beam survival. This may be the case in projects as SIS100 at GSI or LIU at CERN. In the past decade systematic simulation studies and experiments performed at CERN and GSI have highlighted the space charge induced periodic crossing of Â“one dimensionalÂ” resonances as the underlying mechanism of long term beam loss or emittance growth. However only in 2012, for the first time, the effect of space charge on a normal third order coupled resonance was investigated at the CERN-PS. The experimental results have highlighted an unprecedented asymmetric beam response where in the horizontal plane the beam exhibits a thick halo, whereas the vertical profile has only core growth. The quest for explaining these results requires a journey thorough the 4 dimensional dynamics of the coupled resonance investigating the fix-lines, and requires a detailed code-experiment benchmarking also including beam profile benchmarking. This study shows that the experimental results of the 2012 PS measurements can be explained by the dynamics the fixed lines also including the effect of the dispersion.
	Slides WEXB1 [18.195 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEXB1
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THPAB049	Progress in the Understanding of the Performance Limitations in the CERN Low Energy Ion Ring	3819
	A. Huschauer, H. Bartosik, S. Hancock, V. Kain CERN, Geneva, Switzerland
	The performance of heavy ion beams in the CERN Low Energy Ion Ring is mainly limited by beam loss occuring during the radio-frequency capture and the first part of acceleration. Since October 2015, the driving mechanism of these losses has been studied in detail and an interplay of direct space charge forces and excited betatron resonances was identified as the most plausible explanation of the phenomenon. In this paper we summarize the current understanding of the loss mechanism by presenting recent experimental and simulation studies. We discuss strategies to mitigate beam loss and further improve the performance of the accelerator in the future.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPAB049
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THPAB081	The Effects of Space-Charge on the Dynamics of the Ion Booster in the Jefferson Lab EIC (JLEIC)	3906
	E.W. Nissen, S.A. Bogacz JLab, Newport News, Virginia, USA
	Funding: Notice: This manuscript has been authored by Jefferson Science Associates, LLC under Contract No. DE-AC05-06OR23177 with the U.S. Department of Energy. Optimization of the booster synchrotron design to operate in the extreme space-charge dominated regime is proposed. This study is motivated by the ultra-high luminosity promised by the JLEIC accelerator complex, which poses several beam dynamics and lattice design challenges for its individual components. We examine the effects of space charge on the dynamics of the booster synchrotron for the proposed JLEIC electron ion collider. This booster will inject and accumulate protons and heavy ions at an energy of 280 MeV and then engage in a process of acceleration and electron cooling to bring it to its extraction energy of 8 GeV. This would then be sent into the ion collider ring part of JLEIC. In order to examine the effects of space charge on the dynamics of this process we use the software SYNERGIA.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPAB081
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THPVA002	Numerical Investigation of Beam Halo From Beam Gas Scattering in KEK-ATF	4410
	R.J. Yang, P. Bambade LAL, Orsay, France K. Kubo, T. Okugi, N. Terunuma, D. Zhou KEK, Ibaraki, Japan
	To demonstrate the final focus schemes of the Future Linear Collider (FLC), the Accelerator Test Facility 2 (ATF2) at KEK is devoted to focus the beam to a RMS size of a few tens of nanometers (nm) vertically and to provide stability at the nm level at the virtual Interaction Point (IP). However, the loss of halo particles upstream will introduce background to the diagnostic instrument measuring the ultra-small beam, using a laser interferometer monitor. To help the realization of the above goals and beam operation, understanding and mitigation of beam halo are crucial. In this paper, we present the systematical simulation of beam halo formation from beam gas Coulomb scattering (BGS) in the ATF damping ring. The behavior of beam halo with various machine parameters is also discussed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPVA002
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THPVA004	Pushing the Space Charge Limit: Electron Lenses in High-Intensity Synchrotrons?	4417
	W.D. Stem, O. Boine-Frankenheim TEMF, TU Darmstadt, Darmstadt, Germany O. Boine-Frankenheim GSI, Darmstadt, Germany
	Funding: Work is supported by BMBF contract FKZ:05P15RDRBA Several accelerator projects require an increase in the number of particles per bunch, which is constrained by the space charge limit. Above this limit the transverse space charge force in combination with the lattice structure causes beam quality degradation and beam loss. Proposed devices to mitigate this beam loss in ion beams are electron lenses. An electron lens imparts a nonlinear, localized focusing kick to counteract the (global) space-charge forces in the primary beam. This effort is met with many challenges, including a reduced dynamic aperture (DA), resonance crossing, and beam-beam alignment. This contribution provides a detailed study of idealized electron lens use in high-intensity particle accelerators, including a comparison between analytical calculations and pyORBIT particle-in-cell (PIC) simulations.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPVA004
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THPVA015	Application of Modified KV-Distributions to Study the Phase Portrait Transformation of Intense Bunches in Magnetic Fields	4448
	H.Y. Barminova MEPhI, Moscow, Russia
	Modified KV-distribution functions are applied to study the intense bunch behavior in transverse magnetic fields. The functions used allow to consider both the emittance-dominated and charge-dominated bunches in 2D and 3D approximations. Peculiarities of the bunch phase portrait transformation in magnetic fields of achromatic structures are discussed. Particular case is proved to exist characterized by the absence of the emittance transfer.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPVA015
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THPVA021	Dynamics of Spectator Particles in Space-Charge Fields of Mismatched Beams With Cross-Plane Coupling	4462
	M. Holz, V.G. Ziemann Uppsala University, Uppsala, Sweden
	In accelerators with high beam power, even moderate beam losses must be avoided. These losses are due to particles reaching large transverse amplitudes that form a low density halo orbiting the beam core. To study the beam halo formation, we place a spectator particle outside the beam core and let it interact with the core's electric field. The core, we model by a self-consistent transverse Gaussian beam including non-linear space charge forces and cross-plane coupling.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPVA021
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THPVA023	Studies of Longitudinal Beam Stability in CERN PS Booster After Upgrade	4469
SUSPSIK060	use link to see paper's listing under its alternate paper code
	D. Quartullo, S.C.P. Albright, E.N. Shaposhnikova CERN, Geneva, Switzerland
	The CERN PS Booster, comprised of four superposed rings, is the first synchrotron in the LHC proton injection chain. In 2021, after major upgrades, the injection and extraction beam energies, as well as the acceleration rate, will be increased. The required beam intensities should be a factor of two higher for nominal LHC and fixed-target beams, and the currently used narrow-band ferrite systems will be replaced by broad-band Finemet cavities in all four rings. Future beam stability was investigated using simulations with the Beam Longitudinal Dynamics (BLonD) code. The simulation results for existing situation were compared with beam measurements and gave a good agreement. An accurate impedance model, together with a careful estimation of the longitudinal space charge, was used in simulations of the future acceleration cycle in single and double RF, with phase and radial loops and controlled longitudinal emittance blow-up. Since the beam is not ultra-relativistic and fills the whole ring (h=1), the front and multi-turn back wakes were taken into account, as well as the RF feedbacks which reduce the effect of the Finemet impedance at the revolution frequency harmonics.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPVA023
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THPVA024	Controlled Longitudinal Emittance Blow-Up Using Band-Limited Phase Noise in CERN PSB	4473
	D. Quartullo, E.N. Shaposhnikova, H. Timko CERN, Geneva, Switzerland
	Controlled longitudinal emittance blow-up (from 1 eVs to 1.4 eVs) for LHC beams in the CERN PS Booster is currently achievied using sinusoidal phase modulation of a dedicated high-harmonic RF system. In 2021, after the LHC injectors upgrade, 3 eVs should be extracted to the PS. Even if the current method may satisfy the new requirements, it relies on low-power level RF improvements. In this paper another method of blow-up was considered, that is the injection of band-limited phase noise in the main RF system (h=1), never tried in PSB but already used in CERN SPS and LHC, under different conditions (longer cycles). This technique, which lowers the peak line density and therefore the impact of intensity effects in the PSB and the PS, can also be complementary to the present method. The longitudinal space charge, dominant in the PSB, causes significant synchrotron frequency shifts with intensity, and its effect should be taken into account. Another complication arises from the interaction of the phase loop with the injected noise, since both act on the RF phase. All these elements were studied in simulations of the PSB cycle with the BLonD code, and the required blow-up was achieved.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPVA024
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THPVA027	Commissioning and First Results of the IBEX Paul Trap	4481
	S.L. Sheehy, E. Carr, L. Martin JAI, Oxford, United Kingdom K. Budzik Warsaw University, Warsaw, Poland D.J. Kelliher, S. Machida STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom C.R. Prior STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
	The Intense Beam Experiment (IBEX) is a linear Paul trap designed to replicate the dynamics of intense particle beams in accelerators. Similar to the S-POD apparatus at Hiroshima University, IBEX is a small scale experiment which has been constructed and recently commissioned at the Rutherford Appleton Laboratory in the UK. Its aim is to support theoretical studies of next-generation high intensity proton and ion accelerators, complementing existing computer simulation approaches. Here we report on the status of commissioning and first results obtained.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPVA027
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THPVA032	Space-Charge Simulation of Integrable Rapid Cycling Synchrotron	4501
	J.S. Eldred, A. Valishev Fermilab, Batavia, Illinois, USA
	Integrable optics is an innovation in particle accelerator design that enables strong nonlinear focusing without generating parametric resonances. We use a Synergia space-charge simulation to investigate the application of integrable optics to a high-intensity hadron ring that could replace the Fermilab Booster. We find that incorporating integrability into the design suppresses the beam halo generated by a mismatched KV beam. Our integrable rapid cycling synchrotron (iRCS) design includes other features of modern ring design such as low momentum compaction factor and harmonically canceling sextupoles. Experimental tests of high-intensity beams in integrable lattices will take place over the next several years at the Fermilab Integrable Optics Test Accelerator (IOTA) and the University of Maryland Electron Ring (UMER).
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPVA032
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THPVA037	Injection of a Self-Consistent Beam at the Spallation Neutron Source	4516
	J.A. Holmes, S.M. Cousineau, T.V. Gorlov, M.A. Plum ORNL, Oak Ridge, Tennessee, USA
	Funding: ORNL is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. Department of Energy. This research was supported by the DOE Office of Science, Basic Energy Science. We plan to demonstrate the injection of a self-consistent beam into the Spallation Neutron Source (SNS). Self-consistent beams are defined to be ellipsoidal distributions with uniform density and to retain these properties under all linear transformations. Self-consistent distributions may generate very little halo if realized in practice. Some may also be manipulated to generate flat beams. Self-consistent distributions involve very special relationships between the phase space coordinates, making them difficult to realize experimentally. One self-consistent distribution, the 2D rotating distribution, can be painted into the SNS ring, with slight modification of the lattice. However, it is unknown how robust self-consistent distributions will be under real world transport in the presence of nonlinearities and other collective effects. This paper studies these issues and the mitigation of unwanted effects by applying realistic detailed computational models to the simulation of the injection of rotating beams into SNS. The result is a feasible prescription for the injection of a rotating self-consistent distribution into the SNS ring.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPVA037
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Paper

Title

Page

Studies and Observations of Beam Dynamics Near a Sum Resonance

2503

G. Franchetti
GSI, Darmstadt, Germany
S.S. Gilardoni, A. Huschauer, F. Schmidt, R. Wasef
CERN, Geneva, Switzerland

The effect of space charge on bunches stored for long term in a can be severe for beam survival. This may be the case in projects as SIS100 at GSI or LIU at CERN. In the past decade systematic simulation studies and experiments performed at CERN and GSI have highlighted the space charge induced periodic crossing of Â“one dimensionalÂ” resonances as the underlying mechanism of long term beam loss or emittance growth. However only in 2012, for the first time, the effect of space charge on a normal third order coupled resonance was investigated at the CERN-PS. The experimental results have highlighted an unprecedented asymmetric beam response where in the horizontal plane the beam exhibits a thick halo, whereas the vertical profile has only core growth. The quest for explaining these results requires a journey thorough the 4 dimensional dynamics of the coupled resonance investigating the fix-lines, and requires a detailed code-experiment benchmarking also including beam profile benchmarking. This study shows that the experimental results of the 2012 PS measurements can be explained by the dynamics the fixed lines also including the effect of the dispersion.

Slides WEXB1 [18.195 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEXB1

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THPAB049

Progress in the Understanding of the Performance Limitations in the CERN Low Energy Ion Ring

3819

A. Huschauer, H. Bartosik, S. Hancock, V. Kain
CERN, Geneva, Switzerland

The performance of heavy ion beams in the CERN Low Energy Ion Ring is mainly limited by beam loss occuring during the radio-frequency capture and the first part of acceleration. Since October 2015, the driving mechanism of these losses has been studied in detail and an interplay of direct space charge forces and excited betatron resonances was identified as the most plausible explanation of the phenomenon. In this paper we summarize the current understanding of the loss mechanism by presenting recent experimental and simulation studies. We discuss strategies to mitigate beam loss and further improve the performance of the accelerator in the future.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPAB049

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THPAB081

The Effects of Space-Charge on the Dynamics of the Ion Booster in the Jefferson Lab EIC (JLEIC)

3906

E.W. Nissen, S.A. Bogacz
JLab, Newport News, Virginia, USA

Funding: Notice: This manuscript has been authored by Jefferson Science Associates, LLC under Contract No. DE-AC05-06OR23177 with the U.S. Department of Energy.
Optimization of the booster synchrotron design to operate in the extreme space-charge dominated regime is proposed. This study is motivated by the ultra-high luminosity promised by the JLEIC accelerator complex, which poses several beam dynamics and lattice design challenges for its individual components. We examine the effects of space charge on the dynamics of the booster synchrotron for the proposed JLEIC electron ion collider. This booster will inject and accumulate protons and heavy ions at an energy of 280 MeV and then engage in a process of acceleration and electron cooling to bring it to its extraction energy of 8 GeV. This would then be sent into the ion collider ring part of JLEIC. In order to examine the effects of space charge on the dynamics of this process we use the software SYNERGIA.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPAB081

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THPVA002

Numerical Investigation of Beam Halo From Beam Gas Scattering in KEK-ATF

4410

R.J. Yang, P. Bambade
LAL, Orsay, France
K. Kubo, T. Okugi, N. Terunuma, D. Zhou
KEK, Ibaraki, Japan

To demonstrate the final focus schemes of the Future Linear Collider (FLC), the Accelerator Test Facility 2 (ATF2) at KEK is devoted to focus the beam to a RMS size of a few tens of nanometers (nm) vertically and to provide stability at the nm level at the virtual Interaction Point (IP). However, the loss of halo particles upstream will introduce background to the diagnostic instrument measuring the ultra-small beam, using a laser interferometer monitor. To help the realization of the above goals and beam operation, understanding and mitigation of beam halo are crucial. In this paper, we present the systematical simulation of beam halo formation from beam gas Coulomb scattering (BGS) in the ATF damping ring. The behavior of beam halo with various machine parameters is also discussed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPVA002

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THPVA004

Pushing the Space Charge Limit: Electron Lenses in High-Intensity Synchrotrons?

4417

W.D. Stem, O. Boine-Frankenheim
TEMF, TU Darmstadt, Darmstadt, Germany
O. Boine-Frankenheim
GSI, Darmstadt, Germany

Funding: Work is supported by BMBF contract FKZ:05P15RDRBA
Several accelerator projects require an increase in the number of particles per bunch, which is constrained by the space charge limit. Above this limit the transverse space charge force in combination with the lattice structure causes beam quality degradation and beam loss. Proposed devices to mitigate this beam loss in ion beams are electron lenses. An electron lens imparts a nonlinear, localized focusing kick to counteract the (global) space-charge forces in the primary beam. This effort is met with many challenges, including a reduced dynamic aperture (DA), resonance crossing, and beam-beam alignment. This contribution provides a detailed study of idealized electron lens use in high-intensity particle accelerators, including a comparison between analytical calculations and pyORBIT particle-in-cell (PIC) simulations.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPVA004

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THPVA015

Application of Modified KV-Distributions to Study the Phase Portrait Transformation of Intense Bunches in Magnetic Fields

4448

H.Y. Barminova
MEPhI, Moscow, Russia

Modified KV-distribution functions are applied to study the intense bunch behavior in transverse magnetic fields. The functions used allow to consider both the emittance-dominated and charge-dominated bunches in 2D and 3D approximations. Peculiarities of the bunch phase portrait transformation in magnetic fields of achromatic structures are discussed. Particular case is proved to exist characterized by the absence of the emittance transfer.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPVA015

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THPVA021

Dynamics of Spectator Particles in Space-Charge Fields of Mismatched Beams With Cross-Plane Coupling

4462

M. Holz, V.G. Ziemann
Uppsala University, Uppsala, Sweden

In accelerators with high beam power, even moderate beam losses must be avoided. These losses are due to particles reaching large transverse amplitudes that form a low density halo orbiting the beam core. To study the beam halo formation, we place a spectator particle outside the beam core and let it interact with the core's electric field. The core, we model by a self-consistent transverse Gaussian beam including non-linear space charge forces and cross-plane coupling.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPVA021

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THPVA023

Studies of Longitudinal Beam Stability in CERN PS Booster After Upgrade

4469

SUSPSIK060

use link to see paper's listing under its alternate paper code

D. Quartullo, S.C.P. Albright, E.N. Shaposhnikova
CERN, Geneva, Switzerland

The CERN PS Booster, comprised of four superposed rings, is the first synchrotron in the LHC proton injection chain. In 2021, after major upgrades, the injection and extraction beam energies, as well as the acceleration rate, will be increased. The required beam intensities should be a factor of two higher for nominal LHC and fixed-target beams, and the currently used narrow-band ferrite systems will be replaced by broad-band Finemet cavities in all four rings. Future beam stability was investigated using simulations with the Beam Longitudinal Dynamics (BLonD) code. The simulation results for existing situation were compared with beam measurements and gave a good agreement. An accurate impedance model, together with a careful estimation of the longitudinal space charge, was used in simulations of the future acceleration cycle in single and double RF, with phase and radial loops and controlled longitudinal emittance blow-up. Since the beam is not ultra-relativistic and fills the whole ring (h=1), the front and multi-turn back wakes were taken into account, as well as the RF feedbacks which reduce the effect of the Finemet impedance at the revolution frequency harmonics.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPVA023

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

THPVA024

Controlled Longitudinal Emittance Blow-Up Using Band-Limited Phase Noise in CERN PSB

4473

D. Quartullo, E.N. Shaposhnikova, H. Timko
CERN, Geneva, Switzerland

Controlled longitudinal emittance blow-up (from 1 eVs to 1.4 eVs) for LHC beams in the CERN PS Booster is currently achievied using sinusoidal phase modulation of a dedicated high-harmonic RF system. In 2021, after the LHC injectors upgrade, 3 eVs should be extracted to the PS. Even if the current method may satisfy the new requirements, it relies on low-power level RF improvements. In this paper another method of blow-up was considered, that is the injection of band-limited phase noise in the main RF system (h=1), never tried in PSB but already used in CERN SPS and LHC, under different conditions (longer cycles). This technique, which lowers the peak line density and therefore the impact of intensity effects in the PSB and the PS, can also be complementary to the present method. The longitudinal space charge, dominant in the PSB, causes significant synchrotron frequency shifts with intensity, and its effect should be taken into account. Another complication arises from the interaction of the phase loop with the injected noise, since both act on the RF phase. All these elements were studied in simulations of the PSB cycle with the BLonD code, and the required blow-up was achieved.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPVA024

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THPVA027

Commissioning and First Results of the IBEX Paul Trap

4481

S.L. Sheehy, E. Carr, L. Martin
JAI, Oxford, United Kingdom
K. Budzik
Warsaw University, Warsaw, Poland
D.J. Kelliher, S. Machida
STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
C.R. Prior
STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom

The Intense Beam Experiment (IBEX) is a linear Paul trap designed to replicate the dynamics of intense particle beams in accelerators. Similar to the S-POD apparatus at Hiroshima University, IBEX is a small scale experiment which has been constructed and recently commissioned at the Rutherford Appleton Laboratory in the UK. Its aim is to support theoretical studies of next-generation high intensity proton and ion accelerators, complementing existing computer simulation approaches. Here we report on the status of commissioning and first results obtained.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPVA027

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THPVA032

Space-Charge Simulation of Integrable Rapid Cycling Synchrotron

4501

J.S. Eldred, A. Valishev
Fermilab, Batavia, Illinois, USA

Integrable optics is an innovation in particle accelerator design that enables strong nonlinear focusing without generating parametric resonances. We use a Synergia space-charge simulation to investigate the application of integrable optics to a high-intensity hadron ring that could replace the Fermilab Booster. We find that incorporating integrability into the design suppresses the beam halo generated by a mismatched KV beam. Our integrable rapid cycling synchrotron (iRCS) design includes other features of modern ring design such as low momentum compaction factor and harmonically canceling sextupoles. Experimental tests of high-intensity beams in integrable lattices will take place over the next several years at the Fermilab Integrable Optics Test Accelerator (IOTA) and the University of Maryland Electron Ring (UMER).

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPVA032

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THPVA037

Injection of a Self-Consistent Beam at the Spallation Neutron Source

4516

J.A. Holmes, S.M. Cousineau, T.V. Gorlov, M.A. Plum
ORNL, Oak Ridge, Tennessee, USA

Funding: ORNL is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. Department of Energy. This research was supported by the DOE Office of Science, Basic Energy Science.
We plan to demonstrate the injection of a self-consistent beam into the Spallation Neutron Source (SNS). Self-consistent beams are defined to be ellipsoidal distributions with uniform density and to retain these properties under all linear transformations. Self-consistent distributions may generate very little halo if realized in practice. Some may also be manipulated to generate flat beams. Self-consistent distributions involve very special relationships between the phase space coordinates, making them difficult to realize experimentally. One self-consistent distribution, the 2D rotating distribution, can be painted into the SNS ring, with slight modification of the lattice. However, it is unknown how robust self-consistent distributions will be under real world transport in the presence of nonlinearities and other collective effects. This paper studies these issues and the mitigation of unwanted effects by applying realistic detailed computational models to the simulation of the injection of rotating beams into SNS. The result is a feasible prescription for the injection of a rotating self-consistent distribution into the SNS ring.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPVA037

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