Our Activities  >> Nuclear Theory

Nuclear Theory

We are studying a wide range of subjects of subatomic nuclear-particle physics, which cover from fundamental problems to applications. Our tools are physics ideas, analytic and numerical methods using super computers.

The fundamental building block of the matter in the universe is the quarks. The quarks form protons and neutrons, which make up atomic nuclei, the cores of atoms. The nucleus and their constituents are the players of the subatomic world of the strong interaction. Many unresolved problems are waiting for us to be revealed.

(1) Confinement of quarks

Nobody has seen ever before isolated quarks in the proton. Why quarks are confined in the nucleon? This is the problem we approach using supercomputers.

(2) Multi-quark particle

Particles that have four or more quarks have not been clearly observed yet. LEPS team lead by RCNP experimental group has observed an evidence of such a particle. This is particularly important and is one of the major research subject in our group.

(3) Symmetry breaking and the origin of mass

In nature there are symmetries. But it is known that if they are broken, mass of particles are generated and varieties in the universe is created. We try to clarify the mechanism of symmetry breaking using the method of quantum field theories.

(4) The pi-meson which was predicted by Hideki Yukawa is playing a role of glue among nucleons.

But its precise role in nuclear physics is not well understood. We formulate the nuclear physics problem with pions explicitly included, which is very new theoretical approach.

(5) Unstable nuclei

In addition to the well established atomic nuclei, many unstable nuclei is known to exist. They are considered to play important roles in nuclear-synthesis in the early universe or in star-formation. We apply the known nuclear physics knowledge to the problem of star evolution, which is used to solve the mechanism of formation of matter.

(6) Super dense matter

In the early universe, matter is expected to exist under extremely high density. We approach theoretically the questions of quark matter which does not exist in the earth.

Multiquark particle, +

Nucleus with pion clouds

Density distribution of unstable nuclei (theoretical prediction)


  • Home
  • Topics
  • About Us
  • For Students
  • Our Activities
    • Outline
    • Ring Cyclotron Facility
    • Laser Electron Photon Facility
    • Lepton Nuclear Physics
    • Accelerator
    • Nuclear Theory
    • Education
    • Achievements
    • Exhibition
  • For Researchers
  • Access
  • Related Links
  • Sitemap