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arXiv · 2111.05418

Infinite volume, three-body scattering formalisms in the presence of bound states

Sebastian M. Dawid
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Abstract

Strong interactions produce a rich spectrum of resonances that decay into three or more hadrons. Understanding their phenomenology requires a theoretical framework to extract parameters fromexperimental data and Lattice QCD simulations of hadron scattering. Two classes of relativistic three-body approaches are currently being pursued: the EFT-based and unitarity-based one. We consider a model of relativistic three-body scattering with an S-wave bound state in the two-body sub-channel using both formalisms. We present and discuss numerical solutions for the multi-hadron scattering amplitudes in different kinematical regions, obtained from integral equationsof the EFT-based approach. The connection of our work to the ongoing program of computingthe three-body spectrum from the lattice is highlighted. Finally, we show how to generalizethe unitarity-based framework to include all relevant open channels, discuss the nonphysicalsingularities near the physical region, and show how to eliminate them in a simple case.

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Sebastian M. Dawid. 2021-11-09. Infinite volume, three-body scattering formalisms in the presence of bound states. https://arxiv.org/abs/2111.05418

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