Lawrence Berkeley National Laboratory

Prompt Gamma Activation Analysis (PGAA) at nuclear reactors has undergone a renaissance with the advent of modern spectroscopy equipment, development of a precise database for PGAA analysis, and the development of guided neutron beams and remote target facilities far from the reactor core. PGAA at these facilities is complemented by short-lived Neutron Activation Analysis (NAA) because decay gamma rays are observed either simultaneously with prompt gamma rays or separately if the neutron beam is chopped. Activities with half-lives as short as 1 ms can now be analyzed with NAA. Sensitivity of less than 0.1 mg/g of any element except Helium has been achieved with a 106 ncm-2s-1 thermal neutron beam. This kind of analysis has so far been limited to a handful of reactor facilities around the world. At Lawrence Berkeley National Laboratory (LBNL) we are developing a PGAA/NAA analysis system based on a compact, low power, >4'109 n/s D+D (En>2.5 MeV) neutron generator. The generator creates minimal gamma-ray background so detectors can be placed close to the target where the neutron flux is comparable to the guided neutron beam at a reactor. A D+D generator requires less thickness of moderator to thermalize neutrons than a conventional D+T (En>14 MeV) generator and eliminates the environmental and political concerns raised by using tritium. This paper discusses our initial PGAA/NAA experimental results for the LBNL neutron generator and future plans to develop reactor-quality PGAA/NAA analysis in the laboratory.