Recent progress in hypernuclear physics

An important goal of hypernuclear physics is to establish a fundamental understanding of the baryon-baryon interactions. Since experimental data on hyperon-nucleon scattering are scarce and none exist for hyperon-hyperon scattering, spectroscopic studies on the structure of hypernuclei provide absolutely crucial information. Recently, extensive precision theoretical calculations for hypernuclei have been performed. Moreover, high-resolution gamma-ray experimental detailing hypernuclear spectroscopy have been developing rapidly. By comparing these theoretical and experimental results, one can obtain useful information regarding hyperon-nucleon interactions. In the case of double strangeness nuclei such as double $\Lambda$ hypernuclei, recently we have three events by KEK-E373 emulsion data. In emulsion experiments, however, it is difficult to determine the spin- parity or even to know whether an observed even corresponds to a ground or excited state. Therefore, it is essential to compare the emulsion data with theoretical analyses to obtain a proper interpretation. By comparing observed data and theoretical calculation, we succeeded in identifying the states. In the future, we expect to have much data on strangeness S=$-1$ and S=$-2$ hypernuclei. In this talk, I shall report on recent progress in theoretical and experimental studies of hypernuclei and discuss future developments in this fields at J-PARC.