Title Design of light element analysis system in BNCT and every NCT

Introduction: The Monte Carlo simulation is used to enhance reliability in the experiments related to nuclear instruments. in addition, that is used to calculate the different components of the neutron and gamma ray fluxes in boron neutron capture therapy(BNCT) and neutron capture (NCT)applications. BNCT is one of the methods in radiotherapy, that is used the neutron beam for kill the cancer cells. The neutron activation analysis(NAA) is the method for identify light elements that the neutron is captured with light elements nucleus and emits characteristic gamma rays. Materials and Methods: the MCNPX code was used for calculation. Boron and other light elements exist in the liver tissue. The BNCT special set geometry was designed. In this designed, light elements analysis is performed simultaneously with the neutron therapy. The effective parameters such as source location, source type, detector location, detector material, patient couch, energy of source, moderator, collimator type, length and thickness of collimator, distance between sample and source, opening of collimator, geometry and location of detector was designed. Results: the best neutron source for BNCT and light element analysis is expanded neutron spectrum produced by the reactor with Paraffin moderator. Neutron Source Generator with every moderator had low efficiency. Collimator made of graphite, graphene and carbon compounds had better neutron output spectrum. Sodium iodide detector is suitable for the detection of light elements gamma rays. The collimator length 20 cm and thickness 6cm. The detectors are placed in a cylindrical arrangement and They should not be exposed to direct neutron radiation. Conclusion: the MCNP study is one of the best methods for BNCT and NCT. the NAA and BNCT is possible Performing Simultaneously. The expanded neutron spectrum from reactors is suitable for NAA and BNCT.