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Properties of light scalar mesons from lattice QCD

C. McNeile·C. Michael
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Abstract

Lattice QCD with $N_f=2$ flavours of sea quark is used to explore the spectrum and decay of scalar mesons. We are able to determine the $b_1$ - $a_0$ mass difference and this leads to the conclusion that the lightest non-singlet scalar meson ($a_0$) has a mass of 1.01(4) GeV. We determine from the lattice the coupling strength to KK and $πη$. We compute the leptonic decay constant of the lightest non-singlet scalar meson. We discuss the impact of these lattice results on the interpretation of the $a_0(980)$ state. We also discuss $K^*_0$ states.

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BibTeXRIS

C. McNeile, C. Michael. 2006-07-10. Properties of light scalar mesons from lattice QCD. https://doi.org/10.1103/physrevd.74.014508

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