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arXiv · 2312.05085

Feasibility of perturbative generation of bound-states from resonances or virtual states

C. -J. Yang
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Abstract

I investigate whether it is possible to generate bound-states from resonances or virtual states through first-order perturbation theory. Using contact-type potentials as those appeared in pionless effective field theory, I show that it is possible to obtain negative-energy states by sandwiching a next-to-leading order (NLO) interaction with the leading-order (LO) wavefunctions, under the presence of LO resonances or virtual states. However, at least under the framework of time-independent Schr\"odinger equation and Hermitian Hamiltonian, there is an inability to create bound-states with structure similar to those formed by the non-perturbative treatments.

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C. -J. Yang. 2023-12-08. Feasibility of perturbative generation of bound-states from resonances or virtual states. https://doi.org/10.1103/physrevc.109.054003

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