Filtered epithermal quasi-monoenergetic neutron beams at research reactor facilities

Area of Science:

• Nuclear Physics
• Materials Science

Background:

• Research reactors are crucial for generating neutron beams.
• Producing quasi-monoenergetic neutron beams with high purity is essential for various scientific applications.
• Existing methods may suffer from contamination by thermal neutrons, fast neutrons, and gamma rays.

Purpose of the Study:

• To develop and characterize filtered neutron techniques for producing quasi-monoenergetic neutron beams.
• To optimize filter components for enhanced beam purity and intensity.
• To develop a computational tool for simulating and calculating filtered neutron beam properties.

Main Methods:

• Application of filtered neutron techniques at research reactors.
• Utilizing simulation studies to characterize filter components and transmitted beam lines.
• Characterizing filtered beams based on optimal thickness of main and additive filter components.
• Development of a computer code ('QMNB') in MATLAB for calculations.

Main Results:

• Successfully produced quasi-monoenergetic neutron beams in the 1.5-133 keV energy range.
• Optimized filter component thicknesses for improved beam characteristics.
• Achieved high purity and intensity in filtered neutron beams.
• Demonstrated low contamination from thermal emission, fast neutrons, and gamma rays.
• Developed and validated the 'QMNB' simulation code.

Conclusions:

• Filtered neutron techniques are effective for generating high-quality quasi-monoenergetic neutron beams.
• The developed 'QMNB' code provides a valuable tool for designing and optimizing neutron filters.
• The characterized beams are suitable for applications requiring precise neutron energies and minimal background radiation.