Outline of Planned Research

Program C02 Advanced negative muon beam development
Principal Investigator MIYAKE, Yasuhiro (High Energy Accelerator Research Organization (KEK))

Research Objective:
The C02 group aims at developing an ultra-low speed negative muon beam that can be focused at a nanoscale level, and by scanning the converged negative muon beam create a scanning negative muon microscope, which could non-destructively visualize isotopic element and chemical bond distributions three-dimensionally with extreme high sensitivity, and becomes a revolutionary analytical microscopic tool. When a negative muon is captured by an atom in a material, it releases characteristic muonic X-rays with nearly 100% probability, and because their energies are 200 times higher than electronic X-rays, they are easy to detect. Light elements such as hydrogen and lithium, as well as carbon, hydrogen, nitrogen and oxygen, which are the main elements in living organisms, can easily be detected with high sensitivity. For example, by observing while scraping the surface of a rapidly frozen biological sample, it will be possible to comprehensively reconstruct three-dimensional distributions of elements, isotopes and chemical bonds constituting a living body with nanoscale resolution capability, thus providing a new analytical tool to revolutionize biological fields.

Research Goal:
Formation of a negative muon beam that can be focused into a diameter of
   Step 1: few tenth of a millimeter,
   Step 2: a few micrometers,
   Step 3: several tens of nanometers.

Research Plan:
The research plan will be performed in two stages: (1) advanced negative muon, and (2) ultra-low speed negative muon beam development.

(1) Improvements of the Negative Muon Beamline at J-PARC
Improvements of the negative muon beamline at the J-PARC muon experimental facility, which is the foundation of this research project and has already achieved the world's highest intensity pulsed muon beam, will be carried out by online beam monitoring and automatic beam tuning program to obtain a well-focused muon beam at the sample position. Thus, establishing the research environment necessary to promote negative muon research focused on A01, B01 and B02 groups. In FY2018, by introducing a collimator that allows measurement in the air and an advanced beam monitor to realize narrow-momentum muon beam, the experimental environment will be improved for B01 group of non-destructive analysis and C01 group of high-resolution photodetector.

(2) Developments of Ultra-Low Speed Negative Muon Beam
Although the negative muon beam obtained in (1) has high-intensity, it is difficult to focus. Utilizing muon catalyzed fusion reaction as a beam cooling means, ultra-low speed negative muon beam that can be converged up to nanoscale diameter will be developed. Negative muon beam with "high-spatial coherence (= small emittance)" can be focused to a smaller beam size. Therefore, by cooling high-energy negative muons to about several keV by muon catalyzed fusion reaction, and reaccelerating them, the beam can then be converged by using a chromatic aberration correction optical system. Furthermore, by developing an energy dispersion correction device, negative muon beam with "time coherence" in energy and momentum will be realized. Then a scanning negative muon microscope will be developed with high-brightness and excellent temporal and spatial coherence to perform three-dimensional elemental analysis experiments. Ultimately, realizing the world's first ultra-low speed negative muon beam and scanning negative muon microscope.

Schematic view of the negative muon cooling system.
The J-PARC facility, where muon-beam experiments in this project are conducted.


Principal Investigator MIYAKE, Yasuhiro
(Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK-IMSS))
Co-Investigators NAGATANI, Yukinori (KEK-IMSS)  
Research Collaborators SHIMOMURA, Koichiro (KEK-IMSS)  
KAWAMURA, Naritoshi (KEK-IMSS)  
TAMPO, Motonobu (KEK-IMSS)  
ISHIDA, Katsuhiko (RIKEN)  
NINOMIYA, Kazuhiko (Osaka University)  
UENO, Hideki (RIKEN)  
NOMACHI, Masaharu (Osaka University)  

Reference Materials

  • Y. Miyake, K. Shimomura, N. Kawamura, … , P. Strasser, … , S. Takeshita, … , M. Tampo et al., “J-PARC muon facility, MUSE,” JPS Conf. Proc. 21, 011054-1–6 (2018), DOI: 10.7566/JPSCP.21.011054 .
  • M. Katsuragawa, M. Tampo, … ,Y. Miyake, … , T. Takahashi, S. Takeda, S. Watanabe et al., “A compact imaging system with a CdTe double-sided strip detector for non-destructive analysis using negative muonic X-rays,” Nucl. Instrum. Methods Phys. Res. A, in press (2017), DOI: 10.1016/j.nima.2017.11.004 .
  • P. Strasser, … , Y. Miyake et al., “The Development of a Non-Destructive Analysis System with Negative Muon Beam for Industrial Devices at J-PARC MUSE,” M. Tampo, … , N. Kawamura, … , K. Ninomiya, JPS Conf. Proc. 8, 036016-1–6 (Sep. 2015), DOI: 10.7566/JPSCP.8.036016 .
  • H. Okamoto, Y. Nagatani “Entanglement-assisted electron microscopy based on a flux qubit,” Appl. Phys. Lett. 104, 062604-1–4 (Feb. 2014), DOI: 10.1063/1.4865244 .
  • K. Terada, K. Ninomiya, … , Y. Miyake, … , N. Kawamura et al., “A new X-ray fluorescence spectroscopy for extraterrestrial materials using a muon beam,” Sci. Rep. 4, 1–6 (May 2014), DOI: 10.1038/srep05072 .