Professor Ejiri’s research covers a broad spectrum of nuclear and particle physics, including:

1. Nuclear Structures – Nuclear vibrations and rotations.

2. Nuclear Reactions – Pre-equilibrium processes and charge-exchange reactions.

3. Hypernuclear Physics – Hypernuclear structures and reactions.

4. Electroweak Interactions – Nuclear beta and gamma decays.

5. Neutrino Nuclear Physics – Neutrino interactions and double beta decays.

6. Symmetry and Dark Matter – Fundamental symmetries and their implications for cosmology.

The experimental and theoretical research works were carried out at INSICU Univ. Tokyo, NPL Univ. Washington, NBI Univ. Copenhagen, IBL Univ. California, RCNP Osaka Univ., KEK, Kamioka, Ohoto, JASRI Spring8, IIAS Kyoto, ICU and others.

Through these studies, Professor Ejiri has developed advanced experimental frameworks and theoretical frameworks in nuclear particle spectroscopy, making significant contributions to nuclear, hypernuclear, and neutrino nuclear physics.