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arXiv · 1507.08570

$\theta$-dependence of the lightest meson resonances in QCD

Neramballi Ripunjay Acharya·Feng-Kun Guo·Maxim Mai·Ulf-G. Meißner
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Abstract

We derive the pion mass and the elastic pion-pion scattering amplitude in the QCD theta-vacuum up to next-to-leading order in chiral perturbation theory. Using the modified inverse amplitude method, we study the theta-dependence of the mass and width of the light scalar meson sigma(500) and the vector meson rho(770).

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Neramballi Ripunjay Acharya, Feng-Kun Guo, Maxim Mai, Ulf-G. Meißner. 2015-07-30. $\theta$-dependence of the lightest meson resonances in QCD. https://doi.org/10.1103/physrevd.92.054023

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