Speaker
Description
We present a preliminary lattice QCD study of the H-dibaryon at a close-to-physical pion mass from a spectroscopic analysis of the strangeness $S=-2$, iso-singlet baryon-baryon system on the CLS D200 ensemble. This ensemble has $m_\pi \simeq 200~\mathrm{MeV}$ and $m_K \simeq 480~\mathrm{MeV}$, using a $64^3 \times 128$ lattice with spacing $a \simeq 0.065~\mathrm{fm}$ and open temporal boundary conditions. We determine the finite-volume spectrum from a GEVP analysis using a basis of $\Lambda\Lambda$, $N\Xi$, and $\Sigma\Sigma$ interpolating operators with multiple momentum combinations. We then perform a coupled-channel finite-volume analysis using different $K^{-1}$-matrix parametrizations over a broad energy range, featuring energy dependence and channel coupling. We discuss the implications of our preliminary results with respect to the existence of the H-dibaryon.