Effect of isospin averaging for $ppK^-$ kaonic cluster

Abstract

The kaonic cluster ppK^-ppK− is described by isospin-dependent N{\bar K}NK‾ potentials with significant difference between singlet and triplet components. The quasi-bound state energy of the system is calculated based on the configuration space Faddeev equations within isospin and averaged potential models. The isospin averaging of N{\bar K}NK‾ potentials is used to simplify the isospin model to isospinless one. We show that three-body bound state energy E_{3}E3 has a lower bound within the isospin formalism due to relation \left\vert E_{3}(V_{NN}=0)\right\vert<2\left\vert E_{2}\right\vert|E3(VNN=0)|<2|E2|, where E_{2}E2 is the binding energy of isospin singlet state of the N{\bar K}NK‾ subsystem. The averaged potential model demonstrates opposite relation between |E_{2}||E2| and |E_{3}(V_{NN}=0)||E3(VNN=0)|.

Particle configurations in the $NN\bar K$ system

“…[14]. The numerical analysis [15,16] shows that there is a lower bound of the "ppK − energy for the phenomenological potentials having the Gaussian form. The lower bound is about -60 MeV for the N K potential proposed in Ref.…”