Paper detail

Baryons and baryoniums in the perspective of QCD sum rules

Following the experimental confirmation of tetraquark and pentaquark states, the search for hexaquark states has emerged as a new frontier in hadron physics. Recent experimental progress, particularly by the BESIII collaboration, has provided compelling evidence for the existence of near-threshold $p\bar{p}$ bound states. These baryon-antibaryon systems, commonly referred to as baryoniums, are regarded as promising hexaquark candidates. In this article, we provide a comprehensive review of the investigations into baryonium states and their constituents, i.e., baryons, within the framework of QCD sum rules. We delineate the fundamental calculation procedures of this method to facilitate its practical application and benchmark the theoretical predictions against alternative models as well as the latest experimental data.