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arXiv · 2609.36876

Wigner and mirror correlations in nuclear mass predictions with kernel ridge regression

X. H. Wu
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Abstract

Wigner- and mirror-correlated kernel ridge regression (WKRR) and its odd-even extension WKRRoe are developed to improve nuclear mass predictions. The Wigner and mirror correlations are encoded entirely in the kernel functions without introducing more weight parameters. For experimentally known nuclear masses, WKRRoe achieves a leave-one-out root-mean-square deviation of 98.0 keV, which falls below the often-quoted 100-keV scale discussed in connection with chaos-related limits. The gain is mainly concentrated in light nuclei near $N=Z$ and is especially large for mirror pairs. Further tests show that WKRRoe can potentially improve predictions for experimentally unknown nuclei near $N=Z$, particularly when their mirror partners have already been measured.

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X. H. Wu. 2026-09-29. Wigner and mirror correlations in nuclear mass predictions with kernel ridge regression. https://arxiv.org/abs/2609.36876

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