Results of the EURADOS international comparison exercise on neutron spectra unfolding in Bonner spheres spectrometry

TL;DR

This paper reports on an international comparison of neutron spectra unfolding in Bonner spheres spectrometry, highlighting the accuracy and discrepancies in results across different methods and scenarios, and proposing improvements.

Contribution

It provides a comprehensive analysis of neutron spectra unfolding results from multiple participants in various realistic scenarios, identifying key discrepancies and suggesting enhancements.

Findings

Some results agree well with reference solutions

Significant energy-dependent discrepancies were observed

Proposed methods for improving unfolding accuracy

Abstract

This paper summarizes the results obtained from an international comparison exercise on neutron spectra unfolding in Bonner spheres spectrometry, organized within the activities of EURADOS working group 6: computational dosimetry. Four realistic situations were considered: a medical accelerator, a workplace field, an irradiation room and a skyshine scenario. The reference solutions are presented, given in terms of idealized fluence-energy distributions and dose rates, along with details of their derivation using verified Monte Carlo codes. The wide variety of unfolded results that were submitted by the participants are then provided, with some shown to agree well with the reference solutions but others showing significant energy-dependent discrepancies. Finally, explanations for some of these discrepancies are proposed, along with suggested methods for how they might be improved.