Mass of the H-dibaryon

TL;DR

This paper investigates the existence of the H-dibaryon using lattice QCD data, developing a model to extrapolate binding energy to physical quark masses, and concludes it is likely unbound at the physical point.

Contribution

It introduces a controlled chiral extrapolation method to assess the H-dibaryon's binding energy from lattice QCD results.

Findings

H-dibaryon likely unbound by 13 ± 14 MeV at physical quark masses.

Developed a model for quark mass dependence of binding energy.

Supports the hypothesis that the H-dibaryon is not a bound state at physical quark masses.

Abstract

Recent lattice QCD calculations have reported evidence for the existence of a bound state with strangeness -2 and baryon number 2 at quark masses somewhat higher than the physical values. By developing a description of the dependence of this binding energy on the up, down and strange quark masses that allows a controlled chiral extrapolation, we explore the hypothesis that this state is to be identified with the $H$-dibaryon. Taking as input the recent results of the HAL and NPLQCD Collaborations, we show that the $H$-dibaryon is likely to be unbound by $13 \pm 14$ MeV at the physical point.