Bound systems of |$\Xi^-$|–|$^{14}_{}{\rm N}$| are studied via |$\Xi^-$| capture at rest followed by emission of a twin single-|$\Lambda$| hypernucleus in the emulsion detectors. Two events forming extremely deep |$\Xi^-$| bound states were obtained by analysis of a hybrid method in the E07 experiment at J-PARC and reanalysis of the E373 experiment at KEK-PS. The decay mode of one event was assigned as |$\Xi^-+^{14}\!\,\!\!{\rm N}\to^{5}_{\Lambda}\!\!\!{\rm He} + ^{5}_{\Lambda}\!\!{\rm He} + ^{4}\!\!{\rm He} + \mathrm{n}$|⁠. Since there are no excited states for daughter particles, the binding energy of the |$\Xi^-$| hyperon, |$B_{\Xi^-}$|⁠, in the |$^{14}_{}{\rm N}$| nucleus was uniquely determined to be |$6.27 \pm 0.27$| MeV. Another |$\Xi^-$|–|$^{14}_{}{\rm N}$| system via the decay |$^{9}_{\Lambda}{\rm Be} + ^{5}_{\Lambda}\!\!\!{\rm He} + \mathrm{n}$| brings a |$B_{\Xi^-}$| value, |$8.00 \pm 0.77$| MeV or |$4.96 \pm 0.77$| MeV, where the two possible values of |$B_{\Xi^-}$| correspond to the ground and the excited states of the daughter |$^{9}_{\Lambda}{\rm Be}$| nucleus, respectively. Because the |$B_{\Xi^-}$| values are larger than those of the previously reported events (KISO and IBUKI), which are both interpreted as the nuclear |$1p$| state of the |$\Xi^-$|–|$^{14}_{}{\rm N}$| system, these new events give the first indication of the nuclear |$1s$| state of the |$\Xi$| hypernucleus, |$^{15}_{\Xi}{\rm C}$|⁠.

中文翻译：

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第一次观察到|$\Xi$|的核s状态 超核，|$^{15}_{\Xi}{\rm C}$|

|$\Xi^-$| 的有界系统 – |$^{14}_{}{\rm N}$| 通过|$\Xi^-$| 研究 静止捕获，然后发射双单- |$\Lambda$| 乳液检测器中的超核。两个事件形成极深|$\Xi^-$| 通过分析 J-PARC 的 E07 实验中的混合方法和重新分析 KEK-PS 的 E373 实验获得结合态。一个事件的衰减模式被指定为|$\Xi^-+^{14}\!\,\!\!{\rm N}\to^{5}_{\Lambda}\!\!\! {\rm He} + ^{5}_{\Lambda}\!\!{\rm He} + ^{4}\!\!{\rm He} + \mathrm{n}$|⁠。由于子粒子没有激发态，|$\Xi^-$|的结合能 超子，|$B_{\Xi^-}$|⁠, 在|$^{14}_{}{\rm N}$| 核被唯一确定为|$6.27 \pm 0.27$| 兆伏。另一个|$\Xi^-$| – |$^{14}_{}{\rm N}$| 系统通过衰变|$^{9}_{\Lambda}{\rm Be} + ^{5}_{\Lambda}\!\!\!{\rm He} + \mathrm{n}$| 带来一个|$B_{\Xi^-}$| 价值，|$8.00 \pm 0.77$| MeV 或|$4.96 \pm 0.77$| MeV，其中|$B_{\Xi^-}$|的两个可能值 对应于子体的基态和激发态|$^{9}_{\Lambda}{\rm Be}$| 核，分别。因为|$B_{\Xi^-}$|值大于先前报告的事件（KISO 和 IBUKI）的值，它们都被解释为核|$1p$| 状态| $ \ ^兮- $ | – |$^{14}_{}{\rm N}$| 系统，这些新事件给出了核|$1s$|的第一个迹象。状态| $ \ $熙| 超核，|$^{15}_{\Xi}{\rm C}$|⁠。