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arXiv · 2412.09917

Improving the predictive power of empirical shell-model Hamiltonians

J. A. Purcell·B. A. Brown·B. C. He·S. R. Stroberg·W. B. Walters
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Abstract

We present two developments which enhance the predictive power of empirical shell-model Hamiltonians for cases in which calibration data are sparse. A recent improvement in the ab initio derivation of effective Hamiltonians leads to a much better starting point for the optimization procedure. In addition, we introduce a protocol to avoid overfitting, enabling a more reliable extrapolation beyond available data. These developments will enable more robust predictions for exotic isotopes produced at rare isotope beam facilities and in astrophysical environments.

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J. A. Purcell, B. A. Brown, B. C. He, S. R. Stroberg, W. B. Walters. 2024-12-13. Improving the predictive power of empirical shell-model Hamiltonians. https://doi.org/10.1103/physrevc.111.044313

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