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arXiv · 2108.10704

Existence and Non-Existence of Doubly Heavy Tetraquark Bound States

Martin Pflaumer·Luka Leskovec·Stefan Meinel·Marc Wagner
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Abstract

In this work we investigate the existence of bound states for doubly heavy tetraquark systems $ \bar{Q}\bar{Q}'qq' $ in a full lattice-QCD computation, where heavy bottom quarks are treated in the framework of non-relativistic QCD. We focus on three systems with quark content $ \bar{b}\bar{b}ud $, $ \bar{b}\bar{b}us $ and $ \bar{b}\bar{c}ud $. We show evidence for the existence of $ \bar{b}\bar{b}ud $ and $ \bar{b}\bar{b}us $ bound states, while no binding appears to be present for $ \bar{b}\bar{c}ud $. For the bound four-quark states we also discuss the importance of various creation operators and give an estimate of the meson-meson and diquark-antidiquark percentages.

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Martin Pflaumer, Luka Leskovec, Stefan Meinel, Marc Wagner. 2021-08-24. Existence and Non-Existence of Doubly Heavy Tetraquark Bound States. https://doi.org/10.22323/1.396.0392

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