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arXiv · 2310.19547

Expansion of one-, two- and three-body matrix elements on a generic spherical basis for nuclear ab initio calculations

Alberto Scalesi·Carlo Barbieri·Enrico Vigezzi
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Abstract

Ab initio studies of atomic nuclei are based on Hamiltonians including one-, two- and three-body operators with very complicated structures. Traditionally, matrix elements of such operators are expanded on a Harmonic Oscillator single-particle basis, which allows for a simple separation of the center-of-mass motion from the intrinsic one. A few recent investigations have showed that the use of different single-particle bases can bring significant advantages to numerical nuclear structure computations. In this work, the complete analytical expression of the Hamiltonian matrix elements expanded on a generic spherical basis is presented for the first time. This will allow systematic studies aimed at the determination of optimal nuclear bases.

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Alberto Scalesi, Carlo Barbieri, Enrico Vigezzi. 2023-10-30. Expansion of one-, two- and three-body matrix elements on a generic spherical basis for nuclear ab initio calculations. https://doi.org/10.1016/j.aop.2024.169688

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