IPAC2021 - Classification: MC5: Beam Dynamics and EM Fields / D07 High Intensity Circular Machines

Paper	Title	Page
TUPAB234	Exploring Accelerators for Intense Beams with the IBEX Paul Trap	1980
	J.A.D. Flowerdew University of Oxford, Oxford, United Kingdom D.J. Kelliher, S. Machida STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom S.L. Sheehy STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
	Accelerators built from linear components will exhibit bounded and stable particle motion in the ideal case. However, any imperfections in field strength or misalignment of components can introduce chaotic and unstable particle motion. All accelerators are prone to such non-linearities but the effects are even more significant in high intensity particle beams with the presence of space charge effects. This work aims to explore the non-linearities which arise in high intensity particle beams using the scaled experiment, IBEX. The IBEX experiment is a linear Paul trap that allows the transverse dynamics of a collection of trapped particles to be studied by mimicking the propagation through multiple quadrupole lattice periods whilst remaining stationary in the laboratory frame. IBEX is currently undergoing a non-linear upgrade with the goal of investigating Non-linear Integrable Optics (NIO) in order to improve our understanding and utilisation of high intensity particle beams.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB234
About •	paper received ※ 19 May 2021 paper accepted ※ 18 June 2021 issue date ※ 12 August 2021
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WEPAB248	Kurth Vlasov-Poisson Solution for a Beam in the Presence of Time-Dependent Isotropic Focusing	3213
	C.E. Mitchell, K. Hwang, R.D. Ryne LBNL, Berkeley, California, USA
	Funding: This work was supported by the Director, Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. The well-known K-V distribution provides an exact solution of the self-consistent Vlasov-Poisson system describing an unbunched charged particle beam with nonzero temperature in the presence of time-dependent linear transverse focusing. We describe a lesser-known exact solution of the Vlasov-Poisson system that is based on the work of Kurth in stellar dynamics. Unlike the K-V distribution, the Kurth distribution is a true function of the phase space variables, and the solution may be constructed on either the 4D or 6D phase space, for the special case of isotropic linear focusing. Numerical studies are performed for benchmarking simulation codes, and the stability properties of a 4D Kurth distribution are compared with those of a K-V distribution.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB248
About •	paper received ※ 19 May 2021 paper accepted ※ 14 July 2021 issue date ※ 02 September 2021
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WEPAB249	Model of Curvature Effects Associated with Space Charge for Long Beams in Dipoles	3217
	C.E. Mitchell, K. Hwang, R.D. Ryne LBNL, Berkeley, California, USA
	Funding: This work was supported by the Director, Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. For modeling the dynamics within a dipole of a bunch whose length is much larger than the vacuum pipe radius, it is typical to use a 2D (or 2.5D) Poisson solver, with arc length taken as the independent variable. However, sampled at a fixed time, the beam is curved, space charge is not truly 2D, and the usual cancellation between E and B contributions to the Lorentz force need not exactly hold. The size of these effects is estimated using an idealized model of a uniform torus of charge rotating inside a toroidal conducting pipe. Simple expressions are provided for the correction of the electric and magnetic fields to first order in the reciprocal of the curvature radius.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB249
About •	paper received ※ 19 May 2021 paper accepted ※ 02 July 2021 issue date ※ 02 September 2021
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WEPAB250	Interplay Between Space Charge, Intra-Beam Scattering, and Synchrotron Radiation Effects	3220
	M. Zampetakis, F. Antoniou, H. Bartosik, Y. Papaphilippou CERN, Geneva, Switzerland M. Zampetakis University of Crete, Heraklion, Crete, Greece
	The objective of this research is to study the interplay of synchrotron radiation, intra-beam scattering, and space charge in the vicinity of excited resonances. In this respect, two modules were developed to simulate intra-beam scattering and synchrotron radiation effects and plugged into pyORBIT to be used together with its space charge module. Different regimes of synchrotron motion were used to study the response of the beam to a lattice resonance when space charge, intra-beam scattering and synchrotron radiation are present.
	Poster WEPAB250 [0.536 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB250
About •	paper received ※ 17 May 2021 paper accepted ※ 21 July 2021 issue date ※ 25 August 2021
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THPAB241	Examination of Semi-Analytic Model for Mode Coupling Instabilities	4278
	M.A. Balcewicz, Y. Hao FRIB, East Lansing, Michigan, USA M. Blaskiewicz BNL, Upton, New York, USA
	Funding: Work supported by by Brookhaven Science Associates, LLC under contract number 364776. A semianalytic model for studying beams at high SC tune shift is shown. It is a generalization of SWM /ABS for an arbitrary number of longitudinal phase space cycles, yielding more realistic longitudinal physics. The consequences of this generalization are explored; model is benchmarked against TRANFT *** and analytical methods. * Blaskiewicz, Michael. Phys. Rev. ST Accel. Beams, vol. 1, p. 044201, 1998. Burov, Alexey. Phys. Rev. Accel. Beams, vol. 22, p. 034202, 2019. * M. Blaskiewicz, in Proc. PAC07, Albuquerque,
	Poster THPAB241 [0.894 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB241
About •	paper received ※ 19 May 2021 paper accepted ※ 14 July 2021 issue date ※ 14 August 2021
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Paper

Title

Page

Exploring Accelerators for Intense Beams with the IBEX Paul Trap

1980

J.A.D. Flowerdew
University of Oxford, Oxford, United Kingdom
D.J. Kelliher, S. Machida
STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
S.L. Sheehy
STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom

Accelerators built from linear components will exhibit bounded and stable particle motion in the ideal case. However, any imperfections in field strength or misalignment of components can introduce chaotic and unstable particle motion. All accelerators are prone to such non-linearities but the effects are even more significant in high intensity particle beams with the presence of space charge effects. This work aims to explore the non-linearities which arise in high intensity particle beams using the scaled experiment, IBEX. The IBEX experiment is a linear Paul trap that allows the transverse dynamics of a collection of trapped particles to be studied by mimicking the propagation through multiple quadrupole lattice periods whilst remaining stationary in the laboratory frame. IBEX is currently undergoing a non-linear upgrade with the goal of investigating Non-linear Integrable Optics (NIO) in order to improve our understanding and utilisation of high intensity particle beams.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB234

About •

paper received ※ 19 May 2021 paper accepted ※ 18 June 2021 issue date ※ 12 August 2021

Export •

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

WEPAB248

Kurth Vlasov-Poisson Solution for a Beam in the Presence of Time-Dependent Isotropic Focusing

3213

C.E. Mitchell, K. Hwang, R.D. Ryne
LBNL, Berkeley, California, USA

Funding: This work was supported by the Director, Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.
The well-known K-V distribution provides an exact solution of the self-consistent Vlasov-Poisson system describing an unbunched charged particle beam with nonzero temperature in the presence of time-dependent linear transverse focusing. We describe a lesser-known exact solution of the Vlasov-Poisson system that is based on the work of Kurth in stellar dynamics. Unlike the K-V distribution, the Kurth distribution is a true function of the phase space variables, and the solution may be constructed on either the 4D or 6D phase space, for the special case of isotropic linear focusing. Numerical studies are performed for benchmarking simulation codes, and the stability properties of a 4D Kurth distribution are compared with those of a K-V distribution.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB248

About •

paper received ※ 19 May 2021 paper accepted ※ 14 July 2021 issue date ※ 02 September 2021

Export •

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

WEPAB249

Model of Curvature Effects Associated with Space Charge for Long Beams in Dipoles

3217

C.E. Mitchell, K. Hwang, R.D. Ryne
LBNL, Berkeley, California, USA

Funding: This work was supported by the Director, Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.
For modeling the dynamics within a dipole of a bunch whose length is much larger than the vacuum pipe radius, it is typical to use a 2D (or 2.5D) Poisson solver, with arc length taken as the independent variable. However, sampled at a fixed time, the beam is curved, space charge is not truly 2D, and the usual cancellation between E and B contributions to the Lorentz force need not exactly hold. The size of these effects is estimated using an idealized model of a uniform torus of charge rotating inside a toroidal conducting pipe. Simple expressions are provided for the correction of the electric and magnetic fields to first order in the reciprocal of the curvature radius.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB249

About •

paper received ※ 19 May 2021 paper accepted ※ 02 July 2021 issue date ※ 02 September 2021

Export •

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

WEPAB250

Interplay Between Space Charge, Intra-Beam Scattering, and Synchrotron Radiation Effects

3220

M. Zampetakis, F. Antoniou, H. Bartosik, Y. Papaphilippou
CERN, Geneva, Switzerland
M. Zampetakis
University of Crete, Heraklion, Crete, Greece

The objective of this research is to study the interplay of synchrotron radiation, intra-beam scattering, and space charge in the vicinity of excited resonances. In this respect, two modules were developed to simulate intra-beam scattering and synchrotron radiation effects and plugged into pyORBIT to be used together with its space charge module. Different regimes of synchrotron motion were used to study the response of the beam to a lattice resonance when space charge, intra-beam scattering and synchrotron radiation are present.

Poster WEPAB250 [0.536 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB250

About •

paper received ※ 17 May 2021 paper accepted ※ 21 July 2021 issue date ※ 25 August 2021

Export •

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

THPAB241

Examination of Semi-Analytic Model for Mode Coupling Instabilities

4278

M.A. Balcewicz, Y. Hao
FRIB, East Lansing, Michigan, USA
M. Blaskiewicz
BNL, Upton, New York, USA

Funding: Work supported by by Brookhaven Science Associates, LLC under contract number 364776.
A semianalytic model for studying beams at high SC tune shift is shown. It is a generalization of SWM ** /ABS ** for an arbitrary number of longitudinal phase space cycles, yielding more realistic longitudinal physics. The consequences of this generalization are explored; model is benchmarked against TRANFT *** and analytical methods.
* Blaskiewicz, Michael. Phys. Rev. ST Accel. Beams, vol. 1, p. 044201, 1998.
** Burov, Alexey. Phys. Rev. Accel. Beams, vol. 22, p. 034202, 2019.
*** M. Blaskiewicz, in Proc. PAC07, Albuquerque,

Poster THPAB241 [0.894 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB241

About •

paper received ※ 19 May 2021 paper accepted ※ 14 July 2021 issue date ※ 14 August 2021

Export •

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