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arXiv · 1212.1648

Scalar mesons and tetraquarks by means of 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 the light scalar mesons a_0(980) and kappa using N_f = 2+1+1 flavor lattice QCD. In order to probe the internal structure of these scalar mesons, and in particular 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. The inclusion of disconnected diagrams, which are technically rather challenging, but which would allow us to extend our work to e.g. the f_0(980) meson, is introduced and discussed.

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Marc Wagner, Constantia Alexandrou, Jan Oliver Daldrop, Mattia Dalla Brida, Mario Gravina, Luigi Scorzato, Carsten Urbach, Christian Wiese. 2012-12-07. Scalar mesons and tetraquarks by means of lattice QCD. https://arxiv.org/abs/1212.1648

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