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Stopping criteria for neutron spectrum unfolding algorithms
Igor Andrade Machado1, Roberto García-Baonza2, Hector Rene Vega-Carrillo3
1Laboratório de Calibração de Dosímetros. Centro de Desenvolvimento da Tecnologia Nuclear, CDTN, Av. Presidente Antônio Carlos, 6627, Pampulha, CEP: 31270-901, Belo Horizonte, MG, Brazil.
Summary
New Average Ratio Scaled (AVGS) and Relative Change in AVGS (dAVGS) criteria improve neutron spectrum unfolding convergence assessment. These methods offer a robust alternative to the Root Mean Square Error (RMSE) for radiation protection and dosimetry applications.
Area of Science:
- Nuclear physics
- Radiation detection and measurement
Background:
- Neutron spectrum unfolding is vital for radiation protection and dosimetry.
- Iterative algorithms used in unfolding require reliable convergence criteria.
- The Root Mean Square Error (RMSE) is a commonly used but sometimes limited criterion.
Purpose of the Study:
- To introduce and evaluate new convergence criteria for neutron spectrum unfolding.
- To address limitations of the RMSE criterion in specific scenarios.
- To provide improved methods for assessing iterative algorithm convergence in dosimetry.
Main Methods:
- Development of Average Ratio Scaled (AVGS) and Relative Change in AVGS (dAVGS) criteria.
- Extensive validation testing of the new criteria.
- Comparison of AVGS and dAVGS performance against RMSE.
Main Results:
- The new AVGS and dAVGS criteria demonstrated high agreement with reference spectra.
- Validation tests covered a diverse range of unfolding scenarios.
- The proposed criteria offer a viable alternative to RMSE for convergence assessment.
Conclusions:
- AVGS and dAVGS provide effective convergence criteria for neutron spectrum unfolding.
- These new methods enhance the reliability of radiation protection and dosimetry.
- The study validates the utility of AVGS and dAVGS in complex unfolding applications.
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