anti-K anti-K N molecule state in three-body calculation

TL;DR

This paper predicts a weakly bound three-body state involving two anti-kaons and a nucleon, which could correspond to an excited Xi baryon around 1.9 GeV, using non-relativistic three-body calculations.

Contribution

It introduces a novel three-body calculation approach to predict a weakly bound $ar{K}ar{K}N$ state with specific quantum numbers and decay properties.

Findings

Weakly bound $ar{K}ar{K}N$ state below two-body thresholds.

Decay width of 40-60 MeV for the $ar{K}ar{K}N$ system.

Characteristic $ar K N$+$ar K$ cluster structure with spatial extent.

Abstract

A $\bar{K}\bar{K}N$ system with $I=1/2$ and $J^P=1/2^+$ is investigated with non-relativistic three-body calculations by using effective $\bar{K}N$ and $\bar K \bar K$ interactions. The present investigation suggests that a weakly bound state for the $\bar{K}\bar{K}N$ system can be formed below the two-body threshold of $\bar{K}$ and quasibound $\bar{K}N$ with a $40 \sim 60$ MeV decay width of $\bar{K}\bar{K}N\to \pi Y\bar{K}$. This corresponds to an excited $\Xi$ baryon with $J^P=1/2^+$ located around 1.9 GeV. Studying the wave function of the $\bar{K}\bar{K}N$ system obtained in this formulation, we find that the three-body bound system has a characteristic structure of $\bar K N$+$\bar K$ cluster with spatial extent.