Scattered neutron background in thermal neutron detectors
arXiv:1801.05686 · doi:10.1016/j.nima.2018.04.055
Abstract
Inelastic neutron scattering instruments require very low background; therefore the proper shielding for suppressing the scattered neutron background, both from elastic and inelastic scattering is essential. The detailed understanding of the background scattering sources is required for effective suppression. The Multi-Grid thermal neutron detector is an Ar/CO gas filled detector with a BC neutron converter coated on aluminium substrates. It is a large-area detector design that will equip inelastic neutron spectrometers at the European Spallation Source (ESS). To this end a parameterised Geant4 model is built for the Multi-Grid detector. This is the first time thermal neutron scattering background sources have been modelled in a detailed simulation of detector response. The model is validated via comparison with measured data of prototypes installed on the IN6 instrument at ILL and on the CNCS instrument at SNS. The effect of scattering originating in detector components is smaller than effects originating elsewhere.
arXiv commentMinor typos corrected, 2 new references added. Updated simulation geometry in Section 4: extended results and discussion, unchanged main conclusion
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Cited by in corpus (6)
- Detector rates for the Small Angle Neutron Scattering instruments at the European Spallation Source
- Performance evaluation of the Boron Coated Straws detector with Geant4
- Suppression of intrinsic neutron background in the Multi-Grid detector
- Time- and energy-resolved effects in the boron-10 based Multi-Grid and helium-3 based thermal neutron detectors
- Performance study of the Jalousie detector baseline design for the ESS thermal powder diffractometer HEIMDAL through GEANT4 simulations
- Investigation of neutron scattering in the Multi-Blade detector with Geant4 simulations