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Abstract Boron Neutron Capture Therapy (BNCT) beam design needs a special methodology to satisfy the recommended beam parameters required for the proper delivery of treatment doses. In this work, a new design method for a multi-layered spectrum shifter is proposed in order to improve the design process of epithermal BNCT beams for research reactors. The design method is based on two concepts: stepwise spectrum shifting and separation of the design process into two design stages, namely the material selection and the thickness determination. The method has been applied to two case studies using two different sources: a Watt fission neutron spectrum and neutron-gamma spectra of a typical MTRTYPE reactor radial beam. The different beam components have been designed and more concern has been given for the spectrum shifter. Java-based Nuclear Information Software (JANIS) has been used for cross sections computations needed for the selection of the spectrum shifter materials. Monte Carlo N–Particle code “MCNP5” has been used for the beam design. To validate the proposed spectrum shifter design method, comparisons have been done between the proposed spectrum shifter and the known patented material “FLUENTALTM” for both cases. The results of comparisons confirm that the proposed design outperforms the “FLUENTALTM” material. The proposed method proved to be time-saving, simple, effective and efficient. Above all, it is based on a systematic approach rather than the commonly used trial and error approach. Thus, this method can be applied for other epithermal beams as well as other BNCT facilities such as accelerator-based BNCT facilities. This thesis also investigates the present thermal column beam at ETRR-2 reactor. The MCNP model has been validated by comparisons versus experimental results of our measurements and previous measurements as well as other calculations using TRITON code. Also, the design problems in the beam have been analysed. Both of thermal and epithermal BNCT beams are considered. The developed methodology has been applied to design an epithermal BNCT beam in ETRR-2. It has been found that the beam could be very efficient for research purposes, either using thermal or epithermal neutrons. However, using the beam as a thermal facility for clinical treatment will be not feasible. Considering the epithermal BNCT beam for clinical treatment purposes, it has been found to be comparable to Petten BNCT beam. |