First design of a diamond-based neutron spectrometer for cross section measurements

The initial design of a diamond-based neutron spectrometer for fast neutron induced prompt fission neutron spectrum measurements is presented. Initial design investigations have found that coupling a proton radiator to the diamond sensing medium decreases the ultimate neutron energy measurable by a factor of four. The optimum diamond thickness relative to the proton radiator thickness is dependent on the impinging neutron energy. Further, surface texturing is found to only appreciably increase the intrinsic detection efficiency of a given detection system design when the pattern has a depth into the diamond crystal several times the range of the proton in the proton radiator. The geometrical efficiency obstacle found when using a diamond-based detection system is overcome by using a diamond-based fission tagging system, where the expected timing uncertainty may be as low as 64 picoseconds.