IPAC2015 - List of Authors (Berz, M.)

Paper	Title	Page
MOPWA044	Quasi-frozen Spin Method for EDM Deuteron Search	213
	Y. Senichev, A. Lehrach, B. Lorentz, R. Maier FZJ, Jülich, Germany S.N. Andrianov, A.N. Ivanov St. Petersburg State University, St. Petersburg, Russia M. Berz, E. Valetov MSU, East Lansing, Michigan, USA S. Chekmenev RWTH, Aachen, Germany
	To search for EDM using proton storage ring with purely electrostatic elements the concept of frozen spin method has been proposed by BNL. This method is based on two facts: in the equation of the spin precession the magnetic field dependence is entirely eliminated and at “magic” energy the spin precession frequency coincides with the precession frequency of the momentum. In case of deuteron the anomalous magnetic moment is negative (G=-0.142), therefore we have to use the electrical and magnetic field simultaneously keeping the frozen spin direction along the momentum as in the pure electrostatic ring. In this article we suggest the concept of the quasi-frozen spin when the spin oscillates around the momentum direction within the half value of the advanced spin phase each time returning back by special optics. Due to the low value of the anomalous magnetic moment of deuteron an effective contribution to the expected EDM effect is reduced only by a few percent.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPWA044
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WEPWA064	Ionization Cooling Channels in COSY Infinity	2652
	B.T. Loseth, M. Berz MSU, East Lansing, Michigan, USA P. Snopok Illinois Institute of Technology, Chicago, Illinois, USA
	Ionization cooling is a method to reduce the emittance of a beam through the use of absorbers, rf cavities, and strong solenoids for focusing, arranged into a condensed lattice. By tuning lattice parameters, it is possible to construct a staged cooling channel in which the beam emittance is always considerably greater than the minimum value. In the late stages of the cooling channel, space charge effects can become a significant obstacle to further emittance reduction once the beam becomes sufficiently condensed. A method has been implemented in COSY Infinity, a beam dynamics simulation and analysis code, which efficiently and accurately calculates the self-fields of all particles on each other based on a variant of the Fast Multipole Method (FMM). In this paper, we present simulations of a muon ionization cooling channel performed in COSY, utilizing the FMM, benchmarked against G4beamline, a standard code for muon beam analysis, in order to investigate the significance of space charge effects.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPWA064
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WEPWA066	The Advancement of Cooling Absorbers in COSY Infinity	2655
	J.D. Kunz IIT, Chicago, Illinois, USA M. Berz, K. Makino MSU, East Lansing, Michigan, USA P. Snopok Illinois Institute of Technology, Chicago, Illlinois, USA
	Funding: Work is supported by the U.S. Department of Energy. COSY Infinity is an arbitrary-order beam dynamics simulation and analysis code. It can determine high-order transfer maps of combinations of particle optical elements of arbitrary field configurations. For precision modeling, design, and optimization of next-generation muon beam facilities, its features make it a very attractive code. New features are being developed for inclusion in COSY to follow the distribution of charged particles through matter. To study in detail some of the properties of muons passing through material, the transfer map approach alone is not sufficient. The interplay of beam optics and atomic processes must be studied by a hybrid transfer map–Monte-Carlo approach in which transfer map methods describe the average behavior of the particles in the accelerator channel including energy loss, and Monte-Carlo methods are used to provide small corrections to the predictions of the transfer map accounting for the stochastic nature of scattering and straggling of particles. The advantage of the new approach is that it is very efficient in that the vast majority of the dynamics is represented by fast application of the high-order transfer map of an entire element and accumulated stochastic effects as well as possible particle decay. The gains in speed are expected to simplify the optimization of muon cooling channels which are usually very computationally demanding due to the need to repeatedly run large numbers of particles through large numbers of configurations. Progress on the development of the required algorithms is reported.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPWA066
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Paper

Title

Page

Quasi-frozen Spin Method for EDM Deuteron Search

213

Y. Senichev, A. Lehrach, B. Lorentz, R. Maier
FZJ, Jülich, Germany
S.N. Andrianov, A.N. Ivanov
St. Petersburg State University, St. Petersburg, Russia
M. Berz, E. Valetov
MSU, East Lansing, Michigan, USA
S. Chekmenev
RWTH, Aachen, Germany

To search for EDM using proton storage ring with purely electrostatic elements the concept of frozen spin method has been proposed by BNL. This method is based on two facts: in the equation of the spin precession the magnetic field dependence is entirely eliminated and at “magic” energy the spin precession frequency coincides with the precession frequency of the momentum. In case of deuteron the anomalous magnetic moment is negative (G=-0.142), therefore we have to use the electrical and magnetic field simultaneously keeping the frozen spin direction along the momentum as in the pure electrostatic ring. In this article we suggest the concept of the quasi-frozen spin when the spin oscillates around the momentum direction within the half value of the advanced spin phase each time returning back by special optics. Due to the low value of the anomalous magnetic moment of deuteron an effective contribution to the expected EDM effect is reduced only by a few percent.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPWA044

Export •

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

WEPWA064

Ionization Cooling Channels in COSY Infinity

2652

B.T. Loseth, M. Berz
MSU, East Lansing, Michigan, USA
P. Snopok
Illinois Institute of Technology, Chicago, Illinois, USA

Ionization cooling is a method to reduce the emittance of a beam through the use of absorbers, rf cavities, and strong solenoids for focusing, arranged into a condensed lattice. By tuning lattice parameters, it is possible to construct a staged cooling channel in which the beam emittance is always considerably greater than the minimum value. In the late stages of the cooling channel, space charge effects can become a significant obstacle to further emittance reduction once the beam becomes sufficiently condensed. A method has been implemented in COSY Infinity, a beam dynamics simulation and analysis code, which efficiently and accurately calculates the self-fields of all particles on each other based on a variant of the Fast Multipole Method (FMM). In this paper, we present simulations of a muon ionization cooling channel performed in COSY, utilizing the FMM, benchmarked against G4beamline, a standard code for muon beam analysis, in order to investigate the significance of space charge effects.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPWA064

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

WEPWA066

The Advancement of Cooling Absorbers in COSY Infinity

2655

J.D. Kunz
IIT, Chicago, Illinois, USA
M. Berz, K. Makino
MSU, East Lansing, Michigan, USA
P. Snopok
Illinois Institute of Technology, Chicago, Illlinois, USA

Funding: Work is supported by the U.S. Department of Energy.
COSY Infinity is an arbitrary-order beam dynamics simulation and analysis code. It can determine high-order transfer maps of combinations of particle optical elements of arbitrary field configurations. For precision modeling, design, and optimization of next-generation muon beam facilities, its features make it a very attractive code. New features are being developed for inclusion in COSY to follow the distribution of charged particles through matter. To study in detail some of the properties of muons passing through material, the transfer map approach alone is not sufficient. The interplay of beam optics and atomic processes must be studied by a hybrid transfer map–Monte-Carlo approach in which transfer map methods describe the average behavior of the particles in the accelerator channel including energy loss, and Monte-Carlo methods are used to provide small corrections to the predictions of the transfer map accounting for the stochastic nature of scattering and straggling of particles. The advantage of the new approach is that it is very efficient in that the vast majority of the dynamics is represented by fast application of the high-order transfer map of an entire element and accumulated stochastic effects as well as possible particle decay. The gains in speed are expected to simplify the optimization of muon cooling channels which are usually very computationally demanding due to the need to repeatedly run large numbers of particles through large numbers of configurations. Progress on the development of the required algorithms is reported.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPWA066

Export •

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