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  • Open Access

Physics-guided ensemble learning of nuclear masses for astrophysical applications

Srikrishna Agrawal*

N. Chandnani

T. Ghosh and N. Paar

G. Saxena†

B. K. Agrawal

  • Department of Physics, Manipal University Jaipur, Jaipur 303007, India and Department of Physics (H&S), Government Women Engineering College, Ajmer 305002, India

  • Department of Physics, Faculty of Science, University of Zagreb, Bijenička cesta 32, Zagreb 10000, Croatia

  • Department of Physics (H&S), Government Women Engineering College, Ajmer 305002, India

  • *Contact author: agrawalsrikrishna0411@gmail.com
  • †Contact author: gauravphy@gmail.com

APS Open Sci. 1, 000085 – Published 6 August, 2026

DOI: https://doi.org/10.1103/8n1w-f3b7

Abstract

The gradient boosting regressor, an ensemble learning technique, is utilized to correct the residuals in nuclear mass excess across six different nuclear mass models. The corrected residuals are substantially reduced and further improved by applying a weighted averaging method, which benefits from partial error cancellation among the models. Our proposed conflated model, combining ensemble learning with model averaging (ELMA), achieves a root mean square error (RMSE) of approximately 57 keV, well below the critical threshold of 100 keV, for the full dataset of the Atomic Mass Evaluation (AME2020). ELMA also improves predictions for nuclei beyond the training region, with the weighted ensemble reducing the RMSE by approximately 25%–45% relative to the best individual mass model on independent extrapolative datasets. The reliability of the ELMA approach is further validated through the calculation of α-decay Q values, where a clear reduction in deviations from experimental data is observed compared to individual nuclear mass model predictions. We have also compiled a mass excess and binding energy of 6300 nuclei, obtained using our framework and serves as a valuable resource for nuclear physics research and is publicly available through the ELMA web interface (https://ddnp.in/).

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