IPAC2017 - List of Authors (Boine-Frankenheim, O.)

Paper	Title	Page
WEPVA002	Simulations of DLA Grating Structures in the Frequency Domain	3247
SUSPSIK027	use link to see paper's listing under its alternate paper code
	T. Egenolf, O. Boine-Frankenheim, U. Niedermayer TEMF, TU Darmstadt, Darmstadt, Germany O. Boine-Frankenheim GSI, Darmstadt, Germany
	Dielectric laser accelerators (DLA) driven by ultrashort laser pulses can reach orders of magnitude larger gradients than contemporary RF electron accelerators. A new implemented field solver based on the finite element method in the frequency domain allows the calculation of the structure constant, i.e. the ratio of energy gain to laser peak amplitude. We present the maximization of this ratio as a parameter study looking at a single grating period only. Based on this optimized shape the entire design of a beta-matched grating is completed in an iterative process. The period length of a beta-matched grating increases due to the increasing velocity of the electron when a subrelativistic beam is accelerated. The determination of the optimal length of each grating period thus requires the knowledge of the energy gain within all so far crossed periods. Furthermore, we outline to reverse the excitation in the presented solver for beam coupling impedance calculations and an estimation of the beam loading intensity limit.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPVA002
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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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FRXAA1	Laser Cooling of Relativistic Heavy Ion Beams
	M.H. Bussmann, M. Löser HZDR, Dresden, Germany O. Boine-Frankenheim, L. Eidam TEMF, TU Darmstadt, Darmstadt, Germany O. Boine-Frankenheim, L. Eidam, T. Kühl, F. Nolden, R.M. Sanchez Alarcon, M. Steck, T. Stöhlker, D.F.A. Winters GSI, Darmstadt, Germany A. Buss, V. Hannen, D. Winzen Westfälische Wilhelms-Universität Münster, Institut für Kernphysik, Münster, Germany Z. Huang, X. Ma, H. Wang, W.Q. Wen IMP/CAS, Lanzhou, People's Republic of China D. Kiefer, S. Klammes, W. Nörtershäuser, J. Ullmann, T. Walther TU Darmstadt, Darmstadt, Germany U. Schramm TU Dresden, Dresden, Germany U. Schramm, M. Siebold Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Radiation Physics, Dresden, Germany T. Stöhlker IOQ, Jena, Germany T. Stöhlker HIJ, Jena, Germany C. Weinheimer Institut für Kernphysik, Westfälische Wilhelms-Universität Münster, Münster, Germany
	At high energies laser cooling is a very promising technique to reduce phase space of beams of high energy ions effciently and fast. With the advent of new facilities such as FAIR and HIAF research focuses on developing robust laser cooling setups. This requires an understanding of the underlying beam dynamics at high beam intensities, the development of reliable laser systems that can be used to cool a large variety of ion species and optical detection systems that complement standard accelerator beam diagnostics. Based on the lessons learned from ongoing experiments at the ESR at GSI, Darmstadt, and the CSRe at IMP, Lanzhou, the important design aspects of future laser cooling installations will be discussed. The talk will follow a how-to approach to discuss key design aspects of laser cooling setups and emphasize the important connection between advanced beam dynamics studies and optical control and diagnostics.
	Slides FRXAA1 [4.765 MB]
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WEPAB026	BRho-Dependent Taylor Transfer Maps for Super-FRS Dipole Magnets	2631
SUSPSIK049	use link to see paper's listing under its alternate paper code
	E.S. Kazantseva, O. Boine-Frankenheim TEMF, TU Darmstadt, Darmstadt, Germany M. Berz, R. Jagasia, K. Makino MSU, East Lansing, Michigan, USA H. Weick, J.S. Winfield GSI, Darmstadt, Germany
	The Super-FRS is an in-flight projectile fragment separator being built at GSI for FAIR. Due to the required high design momentum resolution and large acceptance (Ah= ±40mrad, Av= ±20mrad) the dipole magnets of the Super-FRS have large apertures (38×14cm²). The wide design magnetic rigidity (BRho) range 2-20 Tm requires the variation of the main dipole magnetic field B0 in the range 0.16-1.6 T. Since the upper third of the B0 range is situated in a non-linear saturation region of the magnetization curve B(H) and the spatial distribution of magnetic permeability in the steel yoke is non-uniform, the field distribution in the useful aperture of the magnet is a non-linear and non-uniform function of the excitation current I. One consequence is the shortening of the effective length and the change of the field distribution with increasing I. In this study we analyze these effects for the Super-FRS dipole magnets. We use 3D field distribution from FEM simulations for different I values and a resulting BRho(I). From the fields the Taylor transfer maps for the particles are obtained using DA techniques (COSY-infinity) and the convergence of the resulting transfer maps is discussed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPAB026
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WEPVA003	Designing a Dielectric Laser Accelerator on a Chip	3250
	U. Niedermayer, O. Boine-Frankenheim, T. Egenolf TEMF, TU Darmstadt, Darmstadt, Germany
	Funding: This work is funded by the Gordon and Betty Moore Foundation (Grant GBMF4744 to Stanford) and the German Federal Ministry of Science and Education (Grant FKZ:05K16RDB). Dielectric Laser Acceleration (DLA) achieves gradients of more than 1GeV/m, which are among the highest in non-plasma accelerators. The long-term goal of the ACHIP collaboration* is to provide relativistic (>1 MeV) electrons by means of a laser driven microchip accelerator. Examples of slightly resonant dielectric structures showing gradients in the range of 70% of the incident laser field (1 GV/m) for electrons with β=0.32 and 200% for β=0.91 are presented. We demonstrate the bunching and acceleration of low energy electrons in dedicated ballistic buncher and velocity matched grating structures. However, the design gradient of 500 MeV/m leads to rapid defocusing. Therefore we present a scheme to bunch the beam in stages, which does not only reduce the energy spread, but also the transverse defocusing. The designs are made with a dedicated homemade 6D particle tracking code. * https://achip.stanford.edu
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPVA003
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Paper

Title

Page

WEPVA002

Simulations of DLA Grating Structures in the Frequency Domain

3247

SUSPSIK027

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

T. Egenolf, O. Boine-Frankenheim, U. Niedermayer
TEMF, TU Darmstadt, Darmstadt, Germany
O. Boine-Frankenheim
GSI, Darmstadt, Germany

Dielectric laser accelerators (DLA) driven by ultrashort laser pulses can reach orders of magnitude larger gradients than contemporary RF electron accelerators. A new implemented field solver based on the finite element method in the frequency domain allows the calculation of the structure constant, i.e. the ratio of energy gain to laser peak amplitude. We present the maximization of this ratio as a parameter study looking at a single grating period only. Based on this optimized shape the entire design of a beta-matched grating is completed in an iterative process. The period length of a beta-matched grating increases due to the increasing velocity of the electron when a subrelativistic beam is accelerated. The determination of the optimal length of each grating period thus requires the knowledge of the energy gain within all so far crossed periods. Furthermore, we outline to reverse the excitation in the presented solver for beam coupling impedance calculations and an estimation of the beam loading intensity limit.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPVA002

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

FRXAA1

Laser Cooling of Relativistic Heavy Ion Beams

M.H. Bussmann, M. Löser
HZDR, Dresden, Germany
O. Boine-Frankenheim, L. Eidam
TEMF, TU Darmstadt, Darmstadt, Germany
O. Boine-Frankenheim, L. Eidam, T. Kühl, F. Nolden, R.M. Sanchez Alarcon, M. Steck, T. Stöhlker, D.F.A. Winters
GSI, Darmstadt, Germany
A. Buss, V. Hannen, D. Winzen
Westfälische Wilhelms-Universität Münster, Institut für Kernphysik, Münster, Germany
Z. Huang, X. Ma, H. Wang, W.Q. Wen
IMP/CAS, Lanzhou, People's Republic of China
D. Kiefer, S. Klammes, W. Nörtershäuser, J. Ullmann, T. Walther
TU Darmstadt, Darmstadt, Germany
U. Schramm
TU Dresden, Dresden, Germany
U. Schramm, M. Siebold
Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Radiation Physics, Dresden, Germany
T. Stöhlker
IOQ, Jena, Germany
T. Stöhlker
HIJ, Jena, Germany
C. Weinheimer
Institut für Kernphysik, Westfälische Wilhelms-Universität Münster, Münster, Germany

At high energies laser cooling is a very promising technique to reduce phase space of beams of high energy ions effciently and fast. With the advent of new facilities such as FAIR and HIAF research focuses on developing robust laser cooling setups. This requires an understanding of the underlying beam dynamics at high beam intensities, the development of reliable laser systems that can be used to cool a large variety of ion species and optical detection systems that complement standard accelerator beam diagnostics. Based on the lessons learned from ongoing experiments at the ESR at GSI, Darmstadt, and the CSRe at IMP, Lanzhou, the important design aspects of future laser cooling installations will be discussed. The talk will follow a how-to approach to discuss key design aspects of laser cooling setups and emphasize the important connection between advanced beam dynamics studies and optical control and diagnostics.

Slides FRXAA1 [4.765 MB]

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WEPAB026

BRho-Dependent Taylor Transfer Maps for Super-FRS Dipole Magnets

2631

SUSPSIK049

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

E.S. Kazantseva, O. Boine-Frankenheim
TEMF, TU Darmstadt, Darmstadt, Germany
M. Berz, R. Jagasia, K. Makino
MSU, East Lansing, Michigan, USA
H. Weick, J.S. Winfield
GSI, Darmstadt, Germany

The Super-FRS is an in-flight projectile fragment separator being built at GSI for FAIR. Due to the required high design momentum resolution and large acceptance (Ah= ±40mrad, Av= ±20mrad) the dipole magnets of the Super-FRS have large apertures (38×14cm²). The wide design magnetic rigidity (BRho) range 2-20 Tm requires the variation of the main dipole magnetic field B0 in the range 0.16-1.6 T. Since the upper third of the B0 range is situated in a non-linear saturation region of the magnetization curve B(H) and the spatial distribution of magnetic permeability in the steel yoke is non-uniform, the field distribution in the useful aperture of the magnet is a non-linear and non-uniform function of the excitation current I. One consequence is the shortening of the effective length and the change of the field distribution with increasing I. In this study we analyze these effects for the Super-FRS dipole magnets. We use 3D field distribution from FEM simulations for different I values and a resulting BRho(I). From the fields the Taylor transfer maps for the particles are obtained using DA techniques (COSY-infinity) and the convergence of the resulting transfer maps is discussed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPAB026

Export •

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

WEPVA003

Designing a Dielectric Laser Accelerator on a Chip

3250

U. Niedermayer, O. Boine-Frankenheim, T. Egenolf
TEMF, TU Darmstadt, Darmstadt, Germany

Funding: This work is funded by the Gordon and Betty Moore Foundation (Grant GBMF4744 to Stanford) and the German Federal Ministry of Science and Education (Grant FKZ:05K16RDB).
Dielectric Laser Acceleration (DLA) achieves gradients of more than 1GeV/m, which are among the highest in non-plasma accelerators. The long-term goal of the ACHIP collaboration* is to provide relativistic (>1 MeV) electrons by means of a laser driven microchip accelerator. Examples of slightly resonant dielectric structures showing gradients in the range of 70% of the incident laser field (1 GV/m) for electrons with β=0.32 and 200% for β=0.91 are presented. We demonstrate the bunching and acceleration of low energy electrons in dedicated ballistic buncher and velocity matched grating structures. However, the design gradient of 500 MeV/m leads to rapid defocusing. Therefore we present a scheme to bunch the beam in stages, which does not only reduce the energy spread, but also the transverse defocusing. The designs are made with a dedicated homemade 6D particle tracking code.
* https://achip.stanford.edu

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPVA003

Export •

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