Modeling of ultra-cold and crystalline ion beams

Okamoto, Hiromi*; Sugimoto, Hiroshi*; Yuri, Yosuke; Ikegami, Masahiro*; Wei, J.*

Proceedings of 10th International Computational Accelerator Physics Conference (ICAP 2009) (Internet), p.151 - 156, 2009/08

Focusing and spectral enhancement of a repetition-rated, laser-driven, divergent multi-MeV proton beam using permanent quadrupole magnets

Nishiuchi, Mamiko; Daito, Izuru; Ikegami, Masahiro; Daido, Hiroyuki; Mori, Michiaki; Orimo, Satoshi; Ogura, Koichi; Sagisaka, Akito; Yogo, Akifumi; Pirozhkov, A. S.; et al.

Applied Physics Letters, 94(6), p.061107_1 - 061107_3, 2009/02

https://doi.org/10.1063/1.3078291

A pair of conventional permanent magnet quadrupoles is used to focus a 2.4 MeV laser-driven proton beam at a 1 Hz repetition rate. The magnetic field strengths are 55 T/m and 60 T/m for the first and second quadrupoles respectively. The proton beam is focused to a spot size (full width at half maximum) of 2.78 mm at a distance of 650 mm from the source. This result is in good agreement with a Monte Carlo particle trajectory simulation.

Crystalline beams in dispersion-free storage rings

Ikegami, Masahiro*; Okamoto, Hiromi*; Yuri, Yosuke

Physical Review Special Topics; Accelerators and Beams, 9(12), p.124201_1 - 124201_11, 2006/12

https://doi.org/10.1103/PhysRevSTAB.9.124201

Generating a multidimensional crystalline beam in a storage ring has been known to be difficult without a special cooling force, i.e., tapered cooling, because of the momentum dispersion induced by bending magnets. It is, however, possible to eliminate the dispersion all around the ring by adding an electric dipole field in each magnetic bending region. A storage ring with such unique deflectors should enable us to reach multidimensional crystalline states with an ordinary "untapered" cooling force. In order to verify this expectation, molecular dynamics simulations are performed to study beam crystallization in several dispersion-free storage rings including the S-LSR at Kyoto University. The present results show that various crystalline states can be established without relying on the tapered force.

Present status of R&D for the superconducting proton linac at JAERI

Mizumoto, Motoharu; Kusano, Joichi; Hasegawa, Kazuo; Ouchi, Nobuo; Oguri, Hidetomo; Ichihara, Masahiro; Tomisawa, Tetsuo; Ito, Takashi; Chishiro, Etsuji*; Ikegami, Masanori*; et al.

KEK Proceedings 99-25, p.3 - 5, 2000/02

no abstracts in English

Cooling simulation of heavy ion beams

Ikegami, Masahiro*; Okamoto, Hiromi*; Yuri, Yosuke; Soda, Hikaru*; Tanabe, Mikio*; Noda, Akira*

no journal, , 

no abstracts in English

Applications of the high intensity short-pulse laser driven MeV proton beam

Nishiuchi, Mamiko; Daito, Izuru; Ikegami, Masahiro; Mori, Michiaki; Orimo, Satoshi; Ogura, Koichi; Sagisaka, Akito; Yogo, Akifumi; Pirozhkov, A. S.; Ma, J.*; et al.

no journal, , 

A laser-driven proton beam with a maximum energy of a few MeV is stably obtained using an ultra-short and high-intensity Titanium Sapphire laser. As compared with the proton beam from the conventional accelerator, this proton beam exhibits peculiar characteristics, such as, more than 10 protons per bunch are produced within a short pulse duration of ps at a source, resulting in a very high peak current. It also exhibits a very low transverse emittance. The proton beam has a divergence angle of 10 degrees and energy spread of 100%. It accompanies electrons and X-rays, which is produced simultaneously. Making the best use of these peculiar characteristics, many possible applications of the laser-driven proton are proposed. In order to make practical laser-driven proton beam for the applications, we carry out series of experiments. We have successfully obtained simultaneous imaging of the target with proton and X-ray or proton and electron beams. In the course of practical use of the proton beam for specific applications, characteristics above should be optimized based on the variations of the applications. For example, in order to apply the laser-driven proton beam for the proton irradiation system, such as used in the medical or the industrial applications, we should obtain focused or parallel proton beam. One of our plans to alter the orbits of the laser-driven protons from the planer tape target is using permanent quadrupole magnets.