$\bar{b}\bar{b}ud$ Tetraquarks with $I(J^P)=0(1^-)$ and $\bar{b}\bar{c}ud$ Tetraquarks with $I(J^P)=0(0^+)$ and $I(J^P)=0(1^+)$ from Lattice QCD Antistatic-Antistatic Potentials

TL;DR

This study uses lattice QCD-derived potentials within the Born-Oppenheimer approximation to investigate heavy tetraquark systems, predicting a resonance in the $ar{b}ar{b}ud$ system and virtual bound states in $ar{b}ar{c}ud$ systems.

Contribution

It extends the Born-Oppenheimer approach with lattice QCD potentials to analyze heavy tetraquarks, including a refined prediction of a resonance and virtual bound states.

Findings

Predicted a tetraquark resonance slightly above the $B^{*}B^{*}$ threshold.

Found virtual bound states in $ar{b}ar{c}ud$ systems for specific quantum numbers.

Extended the approach to mixed heavy quark systems.

Abstract

We study heavy spin effects in $\bar{b}\bar{b}ud$ and $\bar{b}\bar{c}ud$ four-quark systems using the Born-Oppenheimer approximation and existing antistatic-antistatic potentials computed with lattice QCD. We report about a recent refined investigation of the $\bar{b}\bar{b}ud$ system with $I(J^P)=0(1^-)$, where we predicted a tetraquark resonance slightly above the $B^{*}B^{*}$ threshold. Furthermore, we extend our Born-Oppenheimer approach to $\bar{b}\bar{c}ud$ four-quark systems. For quantum numbers $I(J^P)=0(0^+)$ as well as $I(J^P)=0(1^+)$ we find virtual bound states rather far away from the lowest meson-meson thresholds.