The existence of the quasi-bound state in KK¯ NN four-body system

Abstract

The possible existence of quasi-bound state in KK¯ NN with quantum numbers J= 0 and I= 0 on the basis of four-body Alt-Grassberger-Sandhas equations in the momentum representation was investigated. We constructed a separable representation for the subamplitudes in the [3+1] and [2+2] partitions. The separable expansion for the integral kernels in the three- and four-body equations was obtained by using the method of the energy-dependent pole expansion (EDPE). Different separable phenomenological and chiral SU(3) based potentials having the one- and two-pole structure of the Λ(1405) resonance were used to study the dependence of the results on K¯ N- πΣ interaction. It was shown that the four-body KK¯ NN system is bound with a binding energy of BKK¯NN∼ 38–78 MeV and width of ΓKK¯NN= 46 - 118 MeV. © 2022, The Author(s), under exclusive licence to Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature.