Precise test of the Standard Model and beyond such as Supersymmetric model.

Our group mainly studies particle physics phenomenology. Recent cosmological observations strongly suggest that we need new physics in order to explain baryon asymmetry and the existence of dark matter in the universe. By investigating phenomena that cannot be explained by the Standard Model and by looking for a new dynamics or symmetry hidden in nature, we aim to establish the next fundamental theory of elementary particles.

We study new models such as the minimal supersymmetric standard model or the strong coupled Higgs models focusing on theoretical predictions which can be tested in on-going or near future experiments in particle physics and cosmology. We have been making theoretical predictions of new physical effects through radiative corrections using perturbation theory and nonperturbative calculation using lattice gauge theory. Recently, we have also broadened our interest to particle physics in the early universe as a probe of new physics.

Lattice QCD calculation on KEK supercomputer (BlueGene). Flavor mixing in the standard model in Band K- factories have been predicted

Figure of (ρ,η) (parameters for the flavor mixing and CP violation in the standard model ) from the CKM fitter group. Prediction on εK and Δmd,s has played a crucial role in the test of Cabibbo-Kobayashi-Maskawa theory.