Coupled channel approach to strangeness S = -2 baryon-bayron interactions in Lattice QCD

TL;DR

This paper calculates the first lattice QCD potentials for S = -2 baryon-baryon interactions using an extended coupled channel HAL QCD method, revealing their structure and quark mass dependence.

Contribution

It introduces a novel application of the coupled channel HAL QCD method to S = -2 baryon interactions in lattice QCD, including flavor SU(3) breaking effects.

Findings

Potential matrices are successfully extracted from lattice data.

The spatial structure of the potentials is characterized.

Quark mass dependence of the potentials is analyzed.

Abstract

The baryon-baryon interactions with strangeness S = -2 with the flavor SU(3) breaking are calculated for the first time by using the HAL QCD method extended to coupled channel system in lattice QCD. The potential matrices are extracted from the Nambu-Bethe-Salpeter wave functions obtained by the 2+1 flavor gauge configurations of CP-PACS/JLQCD Collaborations with a physical volume of 1.93 fm cubed and with m_pi/m_K = 0.96, 0.90, 0.86. The spatial structure and the quark mass dependence of the potential matrix in the baryon basis and in the SU(3) basis are investigated.