Studies relating to the choice of gamma -ray detectors for in vivo nitrogen measurement by prompt-capture neutron activation analysis

The choice of gamma-ray detectors for in vivo nitrogen determination is examined. NaI(Tl), BiGeO and hyperpure Ge detectors are investigated. It is shown that several small (5.1 cm diameter*10.2 cm long) NaI(Tl) detectors offer advantages over a single large detector (15.2 cm diameter*15.2 cm long). BiGeO has the disadvantage of an interference peak at 10.2 MeV, whilst hyperpure Ge detectors are expensive, and therefore not cost effective, unless used for simultaneous multi-elemental analysis.