Design, construction and characterization of a prompt gamma activation analysis facility at the Oregon State University TRIGAA® reactor

A prompt gamma neutron activation analysis facility has been designed, built, and characterized at the Oregon State University TRIGA(A (R)) reactor. This facility was designed for versatile multi-elemental analyses. The facility utilizes the leakage neutrons originating from beam port #4 of the Oregon State University TRIGA(A (R)) reactor. The neutrons are collimated through a series of lead and Boral(A (R)) collimators, and filtered through both a bismuth filter and single-crystal sapphire. Samples are irradiated in a sample chamber outside the biological shielding of the reactor, and the resulting gamma radiation produced from neutron interactions within the sample is monitored using a high-purity germanium detector (HPGe). The thermal and epithermal neutron fluxes were measured using gold-foil irradiations and found to be 2.81 x 10(7) and 1.70 x 10(4) cm(-2) s(-1), respectively. The resulting cadmium ratio was 106. Measured detection limits for boron, chlorine, and potassium in a NIST SRM 1571 orchard leaf were 5.6 x 10(-4) mg/g, 8.2 x 10(-2) mg/g, and 1.0 mg/g, respectively. Detection limits for additional elements and samples are presented.