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arXiv · 0712.0473

The effect of isospin violation on scalar meson production

C. Hanhart·B. Kubis·J. R. Pelaez
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Abstract

We investigate the isospin-violating mixing of the light scalar mesons a0(980) and f0(980) within the unitarized chiral approach. Isospin-violating effects are considered to leading order in the quark mass difference and electromagnetism. In this approach both resonances are generated through meson-meson dynamics. Our results provide a description of the mixing phenomenon within a framework consistent with chiral symmetry and unitarity, where these resonances are not predominantly quark-antiquark states. We discuss in detail the reactions J/Psi to phi S, where S denotes a suitable pair of pseudo--scalar mesons in the scalar channel, namely pi0 eta, K+K-, and K0 \bar K^0. In this work predictions for the cross section in the kaon channels are given for the first time with isospin violating effects included.

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C. Hanhart, B. Kubis, J. R. Pelaez. 2007-12-04. The effect of isospin violation on scalar meson production. https://arxiv.org/abs/0712.0473

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