Bound kaon approach for the ppK − system in the Skyrme model

Abstract

The lightest nuclear $\overline K$ bound state, ppK −, is investigated in the Skyrme model. We describe the ppK − as two-Skyrmion around which a kaon field fluctuates. The two-Skyrmion is projected onto the (pp) S=0 state using the collective coordinate quantization method. We find that the energy of K − can be considerably small, and that ppK − is a molecular state. The binding energy of the ppK − and the mean pp distance are estimated to be B.E. = 104–126 MeV and $\sqrt{\langle r_{pp}^{2}\rangle}$ = 1.6–1.8 fm, respectively.