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arXiv · 2307.00202

Ab initio translationally invariant nucleon-nucleus optical potentials

M. Burrows·K. D. Launey·A. Mercenne·R. B. Baker·G. H. Sargsyan·T. Dytrych·D. Langr
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Abstract

We combine the \textit{ab initio} symmetry-adapted no-core shell model (SA-NCSM) with the single-particle Green's function approach to construct optical potentials rooted in first principles. Specifically, we show that total cross sections and phase shifts for neutron elastic scattering from a $^4$He target with projectile energies between 0.5 and 10 MeV closely reproduce the experiment. In addition, we discuss an important new development that resolves a long-standing issue with spurious center-of-mass motion in the Green's function formalism for many-body approaches. The new development opens the path for first-principle predictions of cross sections for elastic scattering of single-nucleon projectiles, nucleon capture and deuteron breakup reactions, feasible for a broad range of open-shell spherical and deformed nuclei in the SA-NCSM approach.

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M. Burrows, K. D. Launey, A. Mercenne, R. B. Baker, G. H. Sargsyan, T. Dytrych, D. Langr. 2023-07-01. Ab initio translationally invariant nucleon-nucleus optical potentials. https://doi.org/10.1103/physrevc.109.014616

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