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arXiv · 2512.04517

Complex-energy eigenvector continuation for nuclear many-body broad resonances

Rongzhe Hu·Nicolas Michel·Zhicheng Xu·Jianguo Li·Furong Xu
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Abstract

Broad resonances are a unique phenomenon in nuclear many-body systems. Theoretical studies usually involve the continuum degree of freedom, which drastically increases the model space of calculations, and may lead to non-convergence or instability of computations. In this paper, we present the extension of the eigenvector continuation (EC) method to the complex-energy space to treat the broad resonances of open quantum systems of nuclei. EC provides an efficient method to predict the solution of a large-space many-body problem within a small subspace. Using only a few bound and narrow resonance solutions as input in EC, we can obtain the solution of a broad resonance. We have applied the complex-energy EC to the broad resonances of $^4$H, four-neutron $^4n$, $^6$He and $^7$He systems.

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Rongzhe Hu, Nicolas Michel, Zhicheng Xu, Jianguo Li, Furong Xu. 2025-12-04. Complex-energy eigenvector continuation for nuclear many-body broad resonances. https://doi.org/10.1016/j.physletb.2025.140095

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