The search for the eta' mesic nuclei in the BGOegg experiment

It is predicted that the mass of eta' mesons decreases in nuclei due to the partial restoration of the chiral symmetry. If the eta' mass decreases, the eta' meson and the nuclear form a bound state. We search for the eta' bound state in the BGOegg experiment at the LEPS2 beam line at SPring-8. Using the GeV gamma ray, the eta' meson is produced in 12C (gamma, p) eta' 11B reaction. The eta' production is identified by detecting eta meson from eta' decay using the BGOegg calorimeter. The energy of protons is measured by the RPC-TOF. From the missing mass spectrum, the eta' bound state is searched. This experiment started on May 2014. In this talk, the feasibility of this experiment and the performance of the detectors are described.