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arXiv · 1612.05961

Progress in three-particle scattering from LQCD

Raúl A. Briceño·Maxwell T. Hansen·Stephen R. Sharpe
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Abstract

We present the status of our formalism for extracting three-particle scattering observables from lattice QCD (LQCD). The method relies on relating the discrete finite-volume spectrum of a quantum field theory with its scattering amplitudes. As the finite-volume spectrum can be directly determined in LQCD, this provides a method for determining scattering observables, and associated resonance properties, from the underlying theory. In a pair of papers published over the last two years, two of us have extended this approach to apply to relativistic three-particle scattering states. In this talk we summarize recent progress in checking and further extending this result. We describe an extension of the formalism to include systems in which two-to-three transitions can occur. We then present a check of the previously published formalism, in which we reproduce the known finite-volume energy shift of a three-particle bound state.

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Raúl A. Briceño, Maxwell T. Hansen, Stephen R. Sharpe. 2016-12-18. Progress in three-particle scattering from LQCD. https://doi.org/10.1051/epjconf%2F201713705004

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