Estimate of a 1-MeV equivalent fluence for the McClellan Nuclear Radiation Center

The McClellan Nuclear Radiation Center (MNRC) is a facility which utilizes a TRIGA (training, research, isotope production General Atomics) research reactor for various applications. The facility design is based on production-scale neutron radiography; however, the reactor design is based on utilizing the versatility of the TRIGA, thus lending itself to several additional projects. One of these projects is nuclear hardness testing. To develop this capability, the neutron energy spectrum in the testing location must be evaluated. This [open quotes]characterization[close quotes] process involves a lengthy program of selecting and irradiating activation foils, counting the resulting activation product activity, calculating the neutron fluence from the activity, then assembling the fluences into an energy-dependent neutron spectrum. This spectrum can further be defined by calculating a 1-MeV equivalent fluence. The advantage of determining the 1-MeV equivalent fluence is intercomparison among other nuclear hardness testing facilities. This intercomparison brings the MNRC into the state-of-the-art community of hardness testing facilities.