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arXiv · 1909.05749

Three-body unitarity versus finite-volume $\pi^+\pi^+\pi^+$ spectrum from lattice QCD

M. Mai·M. Döring·C. Culver·A. Alexandru
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Abstract

Strong three-body interactions above threshold govern the dynamics of many exotics and conventional excited mesons and baryons. Three-body finite-volume energies calculated from lattice QCD promise an ab-initio understanding of these systems. We calculate the three-$\pi^+$ spectrum unraveling the three-body dynamics that is tightly intertwined with the $S$-matrix principle of three-body unitarity and compare it with recent lattice QCD results. For this purpose, we develop a formalism for three-body systems in moving frames and apply it numerically.

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M. Mai, M. Döring, C. Culver, A. Alexandru. 2019-09-12. Three-body unitarity versus finite-volume $\pi^+\pi^+\pi^+$ spectrum from lattice QCD. https://doi.org/10.1103/physrevd.101.054510

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