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arXiv · 1105.3366

When hadrons become unstable: a novel type of non-analyticity in chiral extrapolations

F. -K. Guo·C. Hanhart·F. J. Llanes-Estrada·U. -G. Meißner
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Abstract

Hadron masses show a specific dependence on the quark masses. Therefore, the variation of these masses can cause a resonance in a hadronic scattering amplitude to become a bound state. Consequently, the amplitude exhibits a non-analytic behavior at this transition. Crossed amplitudes, where the resonance can be exchanged in the t-channel, can be shown to exhibit the same phenomenon by s-->t analytic continuation. This entails possible kinks in lattice quark mass extrapolations needed to compute hadronic observables.

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F. -K. Guo, C. Hanhart, F. J. Llanes-Estrada, U. -G. Meißner. 2011-05-17. When hadrons become unstable: a novel type of non-analyticity in chiral extrapolations. https://doi.org/10.1016/j.physletb.2011.08.022

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