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arXiv · 1512.05831

The pole structure of the Lambda(1405) in a recent QCD simulation

R. Molina·M. Doring
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Abstract

The $Λ(1405)$ baryon is difficult to detect in experiment, absent in many quark model calculations, and supposedly manifested through a two-pole structure. Its uncommon properties made it subject to numerous experimental and theoretical studies in recent years. Lattice-QCD eigenvalues for different quark masses were recently reported by the Adelaide group. We compare these eigenvalues to predictions of a model based on Unitary Chiral Perturbation Theory. The UCHPT calculation predicts the quark mass dependence remarkably well. It also explains the overlap pattern with different meson-baryon components, mainly $πΣ$ and $\bar KN$, at different quark masses. More accurate lattice QCD data are required to draw definite conclusions on the nature of the $Λ(1405)$.

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R. Molina, M. Doring. 2016-10-05. The pole structure of the Lambda(1405) in a recent QCD simulation. https://doi.org/10.1103/physrevd.94.056010

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