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arXiv · 2305.18790

Effects of multiple single-particle basis states in scattering systems

Curtis D. Abell·Derek B. Leinweber·Anthony W. Thomas·Jia-Jun Wu
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Abstract

Low-lying baryon resonances have been explored using Hamiltonian Effective Field Theory (HEFT), in a formalism where resonances with a three-quark component are described by both two-particle meson-baryon states and a bare basis state. Here, we investigate the use of multiple bare states in the Hamiltonian, to extend the formalism to higher energy ranges, and represent a larger portion of the low-lying baryon spectrum. Introducing a second bare state into a toy model extension of the low-energy $\Delta(1232)$ system, we explore the influence of the second bare state on the position of poles in the infinite-volume $T$-matrix. Considering the same system in a finite-volume, we analyse the finite-volume energy spectrum in the presence of a second bare state, providing insight into the interplay between two bare basis states, representing quark-model states, and the relationship between infinite-volume poles and finite-volume eigenstates.

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Curtis D. Abell, Derek B. Leinweber, Anthony W. Thomas, Jia-Jun Wu. 2023-05-30. Effects of multiple single-particle basis states in scattering systems. https://arxiv.org/abs/2305.18790

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