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arXiv · 2211.06356

Zooming in on Multiquark Hadrons within QCD Sum-Rule Approaches

Wolfgang Lucha·Dmitri Melikhov·Hagop Sazdjian
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Abstract

Aiming at self-consistent descriptions of multiquark hadrons (such as tetraquarks, pentaquarks, hexaquarks) by means of QCD sum rules, we note that the totality of contributions to two-point or three-point correlation functions that involve, respectively, either two or just a single operator capable of interpolating the particular multiquark under study can be straightforwardly disentangled into two disjoint classes defined by unambiguously identifiable members. The first is formed by so-called multiquark-phile contributions which indeed might support multiquarks. In the case of flavour-exotic tetraquarks, by definition composed of four (anti-) quarks of mutually different flavours, a tetraquark-phile contribution has to exhibit two or more gluon exchanges of appropriate topology. The second consists of contributions evidently not bearing any relation to multiquarks; these must be discarded when studying multiquarks by QCD sum rules. The first class only should enter the "multiquark-adequate" QCD sum rules for exotic hadrons.

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Wolfgang Lucha, Dmitri Melikhov, Hagop Sazdjian. 2022-11-11. Zooming in on Multiquark Hadrons within QCD Sum-Rule Approaches. https://doi.org/10.1051/epjconf/202227403004

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