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arXiv · 2506.05512

Simulated-Annealing Optimization of Mean-Field Parameters in a Correlated-Basis Nuclear Model with Realistic Short-Range Correlations

Abstract

We optimize a six-parameter spherical Woods-Saxon mean field within a first-order correlated-basis-function description of finite nuclei containing central, spin-isospin, and tensor Short-Range Correlations (SRC). Monte Carlo importance sampling makes the multidimensional simulated-annealing search practical. The final objective contains 17 selected charge radii compared with a common theoretical scale of 0.030 fm. This light-to-heavy set is a representative compromise between mass-isospin coverage and the cost of repeatedly evaluating the correlated objective;Two independent fits are performed: S/S, in which the SRC theory uses its own fitted parameters, and 0/0, in which the no-SRC theory uses a separately fitted parameter set. A diagnostic S/0 calculation inserts the no-SRC-fitted parameters into the SRC theory. Its radius metric is 17.49 times the S/S value, demonstrating that the mean field must be refitted when explicit SRC are introduced. After separate optimization, radii, charge densities, and elastic form factors show no universal advantage for either consistent route. The corrected genuinely off-diagonal OBDM retains both uncorrelated kernels and the complete spectator-exchange spin contraction. In momentum space, the correlated S/S and diagnostic S/0 calculations generate the several-percent high-momentum strength observed in 12C and 40Ca, whereas the consistent no-SRC route 0/0 does not. The high-momentum tail is therefore the clearest signature of explicit SRC in the present calculation.

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BibTeXRIS

Tianyang Ma, Shalom Shlomo. 2025-06-05. Simulated-Annealing Optimization of Mean-Field Parameters in a Correlated-Basis Nuclear Model with Realistic Short-Range Correlations. https://arxiv.org/abs/2506.05512

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