Study of light $\phi$-mesic nuclei with HAL QCD $\phi N$ interactions

Abstract

We explore the possible existence of light $\phi$-mesic nuclei using HAL QCD $\phi N$ interactions for the $^2S_{1/2}$ and $^4S_{3/2}$ channels. Particularly, using the Faddeev formalism in configuration space, the $\phi NN$ system, and $^{9}_{\phi}$Be and $^{6}_{\phi\phi}$He nuclei within the framework of the three-body cluster model, are investigated. The $\phi\alpha$ effective potential, obtained through a folding procedure, involves the HAL QCD $\phi N$ interaction in the $^4S_{3/2}$ channel which does not lead to a bound state of the $\phi N$ pair while the $\phi N$ $^2S_{1/2}$ channel yields the bound state as the $^3_\phi$H nucleus. The $^4S_{3/2}$ potential ensures that the folding procedure is appropriate because there are no open channels like $\phi+N$ and $\phi +2N $ near or below the $\phi+ 4N$ threshold, and it utilizes different matter distributions of $^4$He proposed in the literature. The folding potential is approximated by the Woods-Saxon formula. The mirror systems $\phi$+$\alpha$+$\alpha$ and $\phi$+$\phi$+$\alpha$ have energy ranges from 1-11 MeV and 3-10~MeV, respectively. The predicted binding energies represent the minimal values for the hypothetical $\phi$ mesic nuclei $^{5}_{\phi}$He, $^{9}_{\phi}$Be and $^{6}_{\phi\phi}$He. The phenomenological $\alpha\alpha$ and $\phi\phi$ potentials are adopted from the literature.