[en] Particle and nuclear studies have been carried out using the nuclear emulsion for a long time, and the nuclear emulsion with high positional resolution is still one of the most powerful detectors in this field. However, a large amount of human workload was needed to analyze huge number of images. Recently, machine learning techniques have been introduced to efficiently detect tracks in the images. In this article, various machine learning methods used in hypernuclear study and their applications are presented. (author)

[en] The ΣN interaction is not much studied than the ΛN interaction. To understand the ΣN interaction, we study Σ hypernuclei. As for the Σ hypernucleus, only the ground state of _Σ⁴He has been observed. To obtain more information about the ΣN interaction, the excited state should be studied. Therefore, we measure the missing-mass of the ⁴He(K^–, π^–)X reaction at p_K^– = 1.5 GeV/c and θ_Lab = 2-14° at the J-PARC K1.8 beam line. The ground state of _Σ⁴He is observed whereas a peak of the excited states is not observed. We also observe suppression of the Σ quasi-free process at smaller angles. (author)

[en] We propose a novel method for producing very-neutron-rich hypernuclei and corresponding resonance states by employing charge-exchange reactions via pp(${}^{12}$C, ${}^{12}$N K${}^{+}$)n$\mathrm{\Lambda <!--\; ??\; -->}$ with single-charge-exchange and ppp(${}^9$Be, ${}^9$C K${}^{+}$)nn$\mathrm{\Lambda <!--\; ??\; -->}$ with double-charge-exchange, both of which produce $\mathrm{\Lambda <!--\; ??\; -->}$K${}^{+}$ in a target nucleus. The feasibility of producing very-neutron-rich hypernuclei using the proposed method was analysed by applying an ultra-relativistic quantum molecular dynamics model to a ${}^6$Li + ${}^{12}$C reaction at 2 A GeV. The yields of very-neutron-rich hypernuclei, signal-to-background ratios, and background contributions were investigated. The proposed method is a powerful tool for studying very-neutron-rich hypernuclei and resonance states with a hyperon for experiments employing the Super-FRS facility at FAIR and HFRS facility at HIAF.

[en] We have measured the inclusive missing-mass spectrum of the ¹²C(K^-, p) reaction at a K^- beam momentum of 1.8 GeV/c. This experiment was carried out as a by-product of a pilot run of the J-PARC E05 experiment, which was conceived to search Ξ-hypernuclei by using the (K^-, K⁺) reaction at J-PARC K1.8 beam line. In present measurement, we study the K-bar-nucleus interaction by comparing the observed missing-mass spectrum with a DWIA calculation. In a preliminary analysis, a 'KINK' structure, which might be originated from the threshold of K^-N → Σπ absorption, was found. (author)