Search for the H-Dibaryon with a Large-Acceptance Hyperon Spectrometer

Recent Lattice QCD calculations predict a weekly bound H-dibaryon or a resonant state near the ΛΛ threshold although definite results should be waited for with physical quark masses. We propose to search for the H-dibaryon in ΛΛ production from (K^-, K⁺) reactions off nuclei and also for the weakly bound H-dibaryon by its weak decays to answer the long-standing question about the existence of the H-dibaryon. For this experiment, we plan to construct a large-acceptance hyperon spectrometer with a time projection chamber to detect Λ particles with a good momentum resolution. This spectrometer will also enhance the capability of hadron physics at J-PARC.