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arXiv · 1212.5055

Scattering in the pion-nucleon negative parity channel in lattice QCD

C. B. Lang·V. Verduci
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Abstract

We study the coupled pion-nucleon system (negative parity, isospin 1/2) based on a lattice QCD simulation for nf=2 mass degenerate light quarks. Both, standard 3-quarks baryon operators as well as meson-baryon (4+1)-quark operators are included. This is an exploratory study for just one lattice size and lattice spacing and at a pion mass of 266 MeV. Using the distillation method and variational analysis we determine energy levels of the lowest eigenstates. Comparison with the results of simple 3-quark correlation studies exhibits drastic differences and a new level appears. A clearer picture of the negative parity nucleon spectrum emerges. For the parameters of the simulation we may assume elastic s-wave scattering and can derive values of the phase shift.

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BibTeXRIS

C. B. Lang, V. Verduci. 2013-02-20. Scattering in the pion-nucleon negative parity channel in lattice QCD. https://doi.org/10.1103/physrevd.87.054502

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