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ADDITIONAL CHARACTERISATION OF THE THERMAL NEUTRON PILE AT THE NATIONAL PHYSICAL LABORATORY, UK
N P Hawkes1, P Kolkowski1, N J Roberts1
1National Physical Laboratory, Hampton Road, Teddington, Middlesex, UK.
Radiation Protection Dosimetry
|October 18, 2017
Summary
Researchers re-evaluated the UK
Area of Science:
- Nuclear Physics
- Metrology
Background:
- The National Physical Laboratory (NPL) operates a thermal neutron facility for neutron metrology.
- This facility utilizes accelerator-produced neutrons moderated by graphite bricks.
- Previous characterization of the neutron field (fluence rate and energy spectrum) exists.
Purpose of the Study:
- To renew and extend the characterization of the thermal neutron facility's neutron field.
- To investigate the impact of structural modifications, such as an enlarged central irradiation cavity.
- To enhance the understanding of the graphite pile's performance.
Main Methods:
- Neutron field characterization using established metrology techniques.
- Monte Carlo (MC) modelling for improved simulation and analysis.
- Comparison of experimental data with simulation results.
Main Results:
- Updated characterization of neutron fluence rate and energy spectrum at various positions.
- Insights into the neutronics of the modified graphite pile.
- Validation of Monte Carlo models for predicting neutron field characteristics.
Conclusions:
- The neutron field in the NPL thermal facility has been successfully re-characterized post-modification.
- Monte Carlo modelling provides a valuable tool for understanding and optimizing the facility's performance.
- The study provides essential data for ongoing neutron metrology applications.
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