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arXiv · 1811.00368

Finite-volume matrix elements of two-body states

Alessandro Baroni·Raúl A. Briceño·Maxwell T. Hansen·Felipe G. Ortega-Gama
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Abstract

In this talk, we present a framework for studying structural information of resonances and bound states coupling to two-hadron scattering states. This makes use of a recently proposed finite-volume formalism to determine a class of observables that are experimentally inaccessible but can be accessed via lattice QCD. In particular, we shown that finite-volume two-body matrix elements with one current insertion can be directly related to scattering amplitudes coupling to the external current. For two-hadron systems with resonances or bound states, one can extract the corresponding form factors of these from the energy-dependence of the amplitudes.

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Alessandro Baroni, Raúl A. Briceño, Maxwell T. Hansen, Felipe G. Ortega-Gama. 2018-11-01. Finite-volume matrix elements of two-body states. https://arxiv.org/abs/1811.00368

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