MITOM: a new unfolding code based on a spectra model method applied to neutron spectrometry
M Tomás1, F Fernández, M Bakali
1Grup de Física de les Radiacions, Universitat Autònoma de Barcelona, Edifici Cc E-08193 Bellaterra, Spain.
Radiation Protection Dosimetry
|September 9, 2004
Summary
The MITOM code accurately unfolds neutron spectrometric measurements using Monte Carlo and Bayesian methods. It provides reliable results for Bonner spheres system (BSS) analysis, validated with ISO sources and facility applications.
Area of Science:
- Nuclear physics
- Radiation detection and measurement
Background:
- Bonner spheres systems (BSS) are crucial for neutron spectrometry.
- Accurate unfolding of neutron energy spectra is essential for radiation safety and research.
- Existing methods may require complex parameterization or lack comprehensive validation.
Purpose of the Study:
- To introduce and validate the MITOM code for neutron energy spectrum unfolding.
- To assess the performance of MITOM with Bonner spheres system (BSS) measurements.
- To demonstrate the code's applicability to characterize neutron sources.
Main Methods:
- Development of the MITOM code at UAB utilizing Monte Carlo simulations.
- Application of Bayesian theorem for iterative solution refinement.
- Initial parameterization of neutron energy components (thermal, intermediate, fast).
- Comparison of calculated and measured count rates to achieve acceptable solutions.
Main Results:
- Good agreement between reference values and unfolded magnitudes for ISO sources.
- Satisfactory characterization of thermal SIGMA and CANEL/T400 neutron sources.
- Demonstrated reliability of the MITOM code for BSS data analysis.
Conclusions:
- The MITOM code is a robust tool for neutron spectrometry unfolding.
- It offers a reliable method for analyzing BSS data and characterizing neutron sources.
- The code's performance is validated through diverse experimental applications.
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