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arXiv · 1707.08983

Chiral symmetry constraints on resonant amplitudes

Peter C. Bruns·Maxim Mai
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Abstract

We discuss the impact of chiral symmetry constraints on the quark-mass dependence of meson resonance pole positions, which are encoded in non-perturbative parametrizations of meson scattering amplitudes. Model-independent conditions on such parametrizations are derived, which are shown to guarantee the correct functional form of the leading quark-mass corrections to the resonance pole positions. Some model amplitudes for $\pi\pi$ scattering, widely used for the determination of $\rho$ and $\sigma$ resonance properties from results of lattice simulations, are tested explicitly with respect to these conditions.

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Peter C. Bruns, Maxim Mai. 2017-07-27. Chiral symmetry constraints on resonant amplitudes. https://doi.org/10.1016/j.physletb.2018.01.006

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