Observation of Double-Strangeness Nuclei at J-PARC

Double-strangeness nuclei, i.e. double hypernuclei and hypernuclei, are few-body nuclear systems containing two strange quarks. They are valuable information sources on the and N interaction, which are essential for understanding baryon-baryon interactions under the flavour SU(3) symmetry. In 2016 and 2017, we conducted the J-PARC E07 experiment to study the double-strangeness nuclei in a hadron experimental facility at J-PARC. J-PARC E07 was conducted using the emulsion-counter hybrid method; it is the most complex experiment on the double-strangeness nuclei. We completed the analysis in the first stage using the method adopted in the experimental proposal. Currently, 33 double-strangeness nucleus events have been detected, three times as much as that of the previous experiments. We succeeded in identifying the nuclide for several events. As typical events, we introduce a double hypernuclei event (MINO) and three ^–^14N bound systems (IBUKI, KINKA, and IRRAWADDY) in this article.