IPAC2014 - List of Authors (Okamoto, H.)

Paper	Title	Page
MOZA01	Ultralow Emittance Beam Production based on Doppler Laser Cooling and Coupling Resonance	28
	A. Noda, M. Nakao NIRS, Chiba-shi, Japan M. Grieser MPI-K, Heidelberg, Germany Z.Q. He FRIB, East Lansing, Michigan, USA Z.Q. He TUB, Beijing, People's Republic of China K. Jimbo Kyoto University, Kyoto, Japan H. Okamoto, K. Osaki HU/AdSM, Higashi-Hiroshima, Japan A.V. Smirnov JINR, Dubna, Moscow Region, Russia H. Souda Gunma University, Heavy-Ion Medical Research Center, Maebashi-Gunma, Japan H. Tongu Kyoto ICR, Uji, Kyoto, Japan Y. Yuri JAEA/TARRI, Gunma-ken, Japan
	Funding: Work supported by Advanced Compact Accelerator Development project by MEXT of Japan. It is also supported by GCOE project at Kyoto University, “The next generation of Physics-Spun from Universality" Doppler laser cooling has been applied to low-energy (40 keV) Mg ions together with the resonant coupling method* at the S-LSR at ICR, Kyoto University,. The S-LSR storage ring has a high super periodicity of 6, which is preferable from the beam dynamical point of view. At S-LSR one dimensional ordering of proton beam was already realized for the first time*. Active three dimensional laser cooling has been experimentally demonstrated for ions with un-negligible velocity (v/c=0.0019, where c is the light velocity) for the first time. Utilizing the above mentioned characteristics of S-LSR, an approach to realize ultralow emittances has been pursuit. To suppress heating effects, due to intra-beam scattering, the circulating ion beam intensity was reduced by scraping and beam emittances of 1.3·10^-11 pi m·rad and 8.5·10^-12 pi m·rad (normalized) have been realized for the horizontal and vertical directions, respectively with the 40 keV Mg ion beam at a beam intensity of ~10⁴, which is the lowest emittance ever attained by laser cooling. From MD computer simulations, it is predicted that reduction of the ion number to about 10³ is needed to realize a crystalline string. H. Okamoto, A.M. Sessler, D. Moehl, Phys. Rev. Lett. 72, 397 (1994). ** T. Shirai et. al., Phys. Rev. Lett. 98, 204801 (2007).
	Slides MOZA01 [13.336 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-MOZA01
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TUPRI009	Study of Resonance Crossing in Non-scaling FFAGs using the S-POD Linear Paul Trap	1571
	D.J. Kelliher, S. Machida, C.R. Prior, S.L. Sheehy STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom K. Fukushima, K. Ito, K. Moriya, H. Okamoto, T. Okano HU/AdSM, Higashi-Hiroshima, Japan
	Experiments on EMMA have shown that with rapid acceleration (~10 turns) a linear non-scaling FFAG can accelerate through several integer tunes without detrimental effects on the beam [1]. Proton and ion applications such as hadron therapy will necessarily have a slower acceleration rate, so their feasibility depends on how harmful resonance crossing is in this regime. A simple and useful tool to answer such fundamental questions is the S-POD linear Paul trap at Hiroshima University, which can be set up to simulate the dynamics of a beam in an FFAG. We report here results of experiments to explore different resonance crossing speeds, quantify beam loss and study nonlinear effects. We also discuss the implications of these experimental results in terms of limits on acceptable acceleration rates and alignment errors. [1] S.Machida et al, Nature Physics, N8, 243-257 (2012)
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRI009
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FRXAA01	Beam Dynamics Studies with Non-neutral Plasma Traps	4052
	H. Okamoto, K. Fukushima, H. Higaki, K. Ito, K. Moriya, T. Okano, K. Osaki HU/AdSM, Higashi-Hiroshima, Japan
	Both Paul ion traps and Penning traps have been employed at Hiroshima University to explore fundamental aspects of space-charge dominated beam dynamics. These compact accelerator-free experiments are based on an isomorphism between non-neutral plasmas in a trap and charged-particle beams traveling in a periodic focusing channel. This talk highlights the recent experimental results on coherent betatron resonances in various strong-focusing lattices, resonance crossing in non-scaling FFAG accelerators, ultra-low emittance beam stability, and halo formation.
	Slides FRXAA01 [5.557 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-FRXAA01
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Paper

Title

Page

Ultralow Emittance Beam Production based on Doppler Laser Cooling and Coupling Resonance

28

A. Noda, M. Nakao
NIRS, Chiba-shi, Japan
M. Grieser
MPI-K, Heidelberg, Germany
Z.Q. He
FRIB, East Lansing, Michigan, USA
Z.Q. He
TUB, Beijing, People's Republic of China
K. Jimbo
Kyoto University, Kyoto, Japan
H. Okamoto, K. Osaki
HU/AdSM, Higashi-Hiroshima, Japan
A.V. Smirnov
JINR, Dubna, Moscow Region, Russia
H. Souda
Gunma University, Heavy-Ion Medical Research Center, Maebashi-Gunma, Japan
H. Tongu
Kyoto ICR, Uji, Kyoto, Japan
Y. Yuri
JAEA/TARRI, Gunma-ken, Japan

Funding: Work supported by Advanced Compact Accelerator Development project by MEXT of Japan. It is also supported by GCOE project at Kyoto University, “The next generation of Physics-Spun from Universality"
Doppler laser cooling has been applied to low-energy (40 keV) Mg ions together with the resonant coupling method* at the S-LSR at ICR, Kyoto University,. The S-LSR storage ring has a high super periodicity of 6, which is preferable from the beam dynamical point of view. At S-LSR one dimensional ordering of proton beam was already realized for the first time**. Active three dimensional laser cooling has been experimentally demonstrated for ions with un-negligible velocity (v/c=0.0019, where c is the light velocity) for the first time. Utilizing the above mentioned characteristics of S-LSR, an approach to realize ultralow emittances has been pursuit. To suppress heating effects, due to intra-beam scattering, the circulating ion beam intensity was reduced by scraping and beam emittances of 1.3·10^-11 pi m·rad and 8.5·10^-12 pi m·rad (normalized) have been realized for the horizontal and vertical directions, respectively with the 40 keV Mg ion beam at a beam intensity of ~10⁴, which is the lowest emittance ever attained by laser cooling. From MD computer simulations, it is predicted that reduction of the ion number to about 10³ is needed to realize a crystalline string.
* H. Okamoto, A.M. Sessler, D. Moehl, Phys. Rev. Lett. 72, 397 (1994).
** T. Shirai et. al., Phys. Rev. Lett. 98, 204801 (2007).

Slides MOZA01 [13.336 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-MOZA01

Export •

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

TUPRI009

Study of Resonance Crossing in Non-scaling FFAGs using the S-POD Linear Paul Trap

1571

D.J. Kelliher, S. Machida, C.R. Prior, S.L. Sheehy
STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
K. Fukushima, K. Ito, K. Moriya, H. Okamoto, T. Okano
HU/AdSM, Higashi-Hiroshima, Japan

Experiments on EMMA have shown that with rapid acceleration (~10 turns) a linear non-scaling FFAG can accelerate through several integer tunes without detrimental effects on the beam [1]. Proton and ion applications such as hadron therapy will necessarily have a slower acceleration rate, so their feasibility depends on how harmful resonance crossing is in this regime. A simple and useful tool to answer such fundamental questions is the S-POD linear Paul trap at Hiroshima University, which can be set up to simulate the dynamics of a beam in an FFAG. We report here results of experiments to explore different resonance crossing speeds, quantify beam loss and study nonlinear effects. We also discuss the implications of these experimental results in terms of limits on acceptable acceleration rates and alignment errors.
[1] S.Machida et al, Nature Physics, N8, 243-257 (2012)

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRI009

Export •

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

FRXAA01

Beam Dynamics Studies with Non-neutral Plasma Traps

4052

H. Okamoto, K. Fukushima, H. Higaki, K. Ito, K. Moriya, T. Okano, K. Osaki
HU/AdSM, Higashi-Hiroshima, Japan

Both Paul ion traps and Penning traps have been employed at Hiroshima University to explore fundamental aspects of space-charge dominated beam dynamics. These compact accelerator-free experiments are based on an isomorphism between non-neutral plasmas in a trap and charged-particle beams traveling in a periodic focusing channel. This talk highlights the recent experimental results on coherent betatron resonances in various strong-focusing lattices, resonance crossing in non-scaling FFAG accelerators, ultra-low emittance beam stability, and halo formation.

Slides FRXAA01 [5.557 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-FRXAA01

Export •

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