Strong binding and shrinkage of single and double nuclear systems (K−pp, K−ppn, K−K−p and K−K−pp) predicted by Faddeev-Yakubovsky calculations
Strong binding and shrinkage of single and double nuclear systems (K−pp, K−ppn, K−K−p and K−K−pp) predicted by Faddeev-Yakubovsky calculations
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DOI：
10.2183/pjab.89.418
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发表时间：
2013-07
期刊：
影响因子：
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通讯作者：
S. Maeda;Y. Akaishi;T. Yamazaki
中科院分区：
文献类型：
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作者：
S. Maeda;Y. Akaishi;T. Yamazaki
对 K−pp、K−ppn、KK−K−p 和 K−K−pp 高子核簇进行了非相对论性 Faddeev 和 Faddeev-Yakubovsky 计算，其中通过对 K−-K− 和 K−- 核子相互作用以及核子-核子相互作用采用实数可分离势模型，将准束缚态视为束缚态。发现针对不同的相互作用值获得的这些状态的结合能和空间收缩随着相互作用强度的增加而迅速增加。它们的行为显示在参考图中，其中给出了通过改变致密核介质中的相互作用而可能发生的变化。使用 K−p 的 PDG 质量为 1405 MeV/c2 的 Λ(1405) ansatz，获得以下基态结合能和波函数：51.5 MeV (K−pp)、69 MeV (K−ppn)、30.4 MeV (K−K−p) 和 93 MeV (KK−K−pp)，这与之前的变分法结果非常一致基于赤石-山崎耦合通道势的计算。尽管存在内部 NN 排斥力，但 K−K−pp 态的密度显着增加，其中两个核子彼此非常接近。对计算出的非相对论结果的相对论修正表明，束缚态质量（尤其是 K−K−pp）向 kaon 凝聚状态显着降低。最近观察到的 K−pp 结合能比最初预测的结合能大得多（2 倍）这一事实可能表明，由于手性对称性恢复，致密核中的相互作用增强了约 25%。在这方面，基于 Brown、Kubodera 和 Rho 的“清除 QCD 真空”模型给出了一些定性说明。
Non-relativistic Faddeev and Faddeev-Yakubovsky calculations were made for K−pp, K−ppn, K−K−p and K−K−pp kaonic nuclear clusters, where the quasi bound states were treated as bound states by employing real separable potential models for the K−-K− and the K−-nucleon interactions as well as for the nucleon-nucleon interaction. The binding energies and spatial shrinkages of these states, obtained for various values of the interaction, were found to increase rapidly with the interaction strength. Their behaviors are shown in a reference diagram, where possible changes by varying the interaction in the dense nuclear medium are given. Using the Λ(1405) ansatz with a PDG mass of 1405 MeV/c2 for K−p, the following ground-state binding energies together with the wave functions were obtained: 51.5 MeV (K−pp), 69 MeV (K−ppn), 30.4 MeV (K−K−p) and 93 MeV (K−K−pp), which are in good agreement with previous results of variational calculation based on the Akaishi-Yamazaki coupled-channel potential. The K−K−pp state has a significantly increased density where the two nucleons are located very close to each other, in spite of the inner NN repulsion. Relativistic corrections on the calculated non-relativistic results indicate substantial lowering of the bound-state masses, especially of K−K−pp, toward the kaon condensation regime. The fact that the recently observed binding energy of K−pp is much larger (by a factor of 2) than the originally predicted one may infer an enhancement of the interaction in dense nuclei by about 25% possibly due to chiral symmetry restoration. In this respect some qualitative accounts are given based on “clearing QCD vacuum” model of Brown, Kubodera and Rho.