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arXiv · 2010.09820

Solving relativistic three-body integral equations in the presence of bound states

Andrew W. Jackura·Raúl A. Briceño·Sebastian M. Dawid·Md Habib E Islam·Connor McCarty
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Abstract

We present a systematically improvable method for numerically solving relativistic three-body integral equations for the partial-wave projected amplitudes. The method consists of a discretization procedure in momentum space, which approximates the continuum problem with a matrix equation. It is solved for different matrix sizes, and in the end, an extrapolation is employed to restore the continuum limit. Our technique is tested by solving a three-body problem of scalar particles with an $S$ wave two-body bound state. We discuss two methods of incorporating the pole contribution in the integral equations, both of them leading to agreement with previous results obtained using finite-volume spectra of the same theory. We provide an analytic and numerical estimate of the systematic errors. Although we focus on kinematics below the three-particle threshold, we provide numerical evidence that the methods presented allow for determination of amplitude above this threshold as well.

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Andrew W. Jackura, Raúl A. Briceño, Sebastian M. Dawid, Md Habib E Islam, Connor McCarty. 2020-10-19. Solving relativistic three-body integral equations in the presence of bound states. https://doi.org/10.1103/physrevd.104.014507

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