Planned Research
B02: Basic Research of in-Flight Muon Catalyzed Fusion in the Mach Shock Wave Interference Region

When a muon (μ) binds a deuteron (d) and a triton (t) to make a muonic molecule (dtμ), nuclear fusion reaction d + t4He + n + 17.6 MeV occurs in the muonic molecule. After the nucrear fusion reaction, the muon forms another dtμ molecule and causes a nuclear fusion reaction, again. This phenomenon that the muon successively induces the nuclear fusion reaction. This series of processes is called "muon catalyzed fusion (μCF). The μCF was expected to be a future energy source, and so far a lot of research had been attempted. However, there was a problem that the energy obtained by the μCF has not reached the equivalent energy to create a muon.

In the present project, we propose new ideas that will be a break-through of μCF, and verify their feasibility. In the conventional μCF, there are rate-limiting processes such as muon transfer and muon molecular formation processes at cryogenic temperature. In order to avoid these rate-limiting process, we adopt a new process of the nuclear fusion reaction which occurs during a muon atomic collision at high temperature (dμ + t4He + n + μ + 17.6 MeV and dμ + t4He + n + μ + 17.6 MeV). If the target is sufficiently heated by the nuclear fusion energy, the muon can also induced nuclear fusion reaction succesively. This mechanism can be called in-flight muon catalyzed fusion (IFμCF). To verify the IFμCF, we will study muon atomic processes including nuclear reaction from both theoretical and experimental point of view.

In the theoretical study, we develop a “non-adiabatic coupled rearrangement channel method&rdquo based on a rigorous quantum few body theory, and perform precise calculation incorporating the degrees of freedom of both nuclei and muonic atoms/molecules. In addition to the nuclear fusion reaction cross section of IFμCF, calculate various muon atomic processes related to the experiment by using supercomputer. In addition, since this theoretical method is a high versatility method that does not use any approximation depending on constituent particles of the system, it can be applied to other theoretical problems in the Scientific Research on Innovative Areas.

Figure: Muon target including Mach shock wave interference region. Deuterium and tritium gas mixture flows at high speed from left to right. Pressure in the tube sharply increases in the Mach shock wave interference region, creating high density region. Injected muons stop in this high density region and form muonic atoms, causing in flight muon catalytic fusion (IF μCF) via muon atomic collisions.
   In the experimental study, we develop a new muon target including Mach shock wave interference region (Figure) in order to realize IFμCF. This target applies supersonic airflow of the deuterium and tritium gas mixture to the shock wave generator. The superposition of the shock waves creates a metastable and high density interference region. The advantage of this device is that the pressure in the container is around 1 atm except for the interference region, so we can place detectors to monitor the reaction relatively freely. By circulating the gas, He particles and thermal energy generated by the nuclear fusion reaction can be efficiently collected. Compareing with the few-body theory, we analyze the muon atomic processes in the IFμCF measured by state-of-the-art detectors developed in the Scientific Research on Innovative Areas.


Principal Investigator KINO, Yasushi
(Graduate School of Science, Tohoku University)
Co-Investigator SATO, Motoyasu (Chubu University)  
TANAHASHI, Yoshiharu (Chubu University)  
YAMAMOTO, Norimasa (Chubu University)  
OKADA, Shinji (Chubu University)  
OKA, Toshitaka (JAEA)  
Research Collaborators OKUTSU, Kenichi (Tohoku University)  
KUDO, Hiroshi (Tohoku University)  
NAKAMURA, Satoshi N. (Tohoku University)  
YAMASHITA, Takuma (Tohoku University)  
MUTO, Takashi (Chubu University)  
HIROOKA, Yoshihiko (Chubu University)  
MATSUBARA, Akihiro (Chubu University)  
TAKANO, Hirohisa (Chubu University)  
ITOH, Kimitaka (Chubu University)  
AZUMA, Toshiyuki (RIKEN)  
KAWAMURA, Naritoshi (KEK)  
MATOBA, Shiro (KEK)  
HIYAMA, Emiko (Kyushu University)  
NOMACHI, Masaharu (Osaka University)  

Reference Materials

  • T. Yamashita, M. Umair, Y. Kino, “Bound and resonance states of positronic copper atoms,” J. Phys. B: At. Mol. Opt. Phys. 50, 205002 (2017), DOI: 10.1088/1361-6455/aa8b3b .
  • H. A. Sakaue, D. Kato, N. Yamamoto, N. Nakamura, and I. Murakami, “Spectra of W19+-W32+ observed in the EUV region between 15 and 55 Å with an electron beam ion trap,” Phys. Rev. A 92, 012504 (2015), DOI: 10.1103/PhysRevA.92.012504 .
  • H. Yokoe, T. Sugimura, Y. Tanahashi, “Numerical simulation on interaction of a detonation wave with a shock wave using detailed chemical reaction,” J. Jpn Soc. Fluid Mech. NAGARE 34, 157–165 (2015), .
  • M. Sato, J. Fukushima, S. Takayama, “An explanation of microwave effects by expansion of transit state theories with disturbed velocity, distributions by microwave,” Am. Ceram. Soc. Ceram. Transact. MS&T 13, 1 (2013).
  • E. Hiyama, Y. Kino, M. Kamimura, “Gaussian expansion method for few-body systems,” Prog. Part. Nucl. Phys. 51, 223–307 (2003), DOI: 10.1016/S0146-6410(03)90015-9 .