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arXiv · 1302.3389

Scalar mesons and tetraquarks from twisted mass lattice QCD

Marc Wagner·Constantia Alexandrou·Jan Oliver Daldrop·Mattia Dalla Brida·Mario Gravina·Luigi Scorzato·Carsten Urbach·Christian Wiese
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Abstract

We study light scalar mesons with particular focus on the a_0(980) using lattice QCD with 2+1+1 dynamical quark flavors. To investigate the structure of these scalar mesons and to identify, whether a sizeable tetraquark component is present, we use a large set of operators, including diquark-antidiquark, mesonic molecule and two-meson operators. We find that the low-lying states overlap essentially exclusively with two-meson states. This indicates that in the channels investigated no tightly bound four-quark states of either molecular or diquark-antidiquark type exist.

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Marc Wagner, Constantia Alexandrou, Jan Oliver Daldrop, Mattia Dalla Brida, Mario Gravina, Luigi Scorzato, Carsten Urbach, Christian Wiese. 2013-02-14. Scalar mesons and tetraquarks from twisted mass lattice QCD. https://arxiv.org/abs/1302.3389

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