Estimation of the smallest detail discernible in track-etch autoradiograph

An analytical model of the recording process in neutron induced autoradiography (NIA) utilizing solid state nuclear track detectors (SSNTD-s) is presented. The model is based on analysis of the inhomogenity of the image caused by statistical fluctuation in the number of tracks forming the image. With this model one can estimate the smallest detail discernible in an autoradiograph as a function of the confidence factor, the neutron exposure, the response of the SSNTD to neutrons for the element of interest and the bulk material the concentration of the element, the natural background, the track size and the unsharpness of the image. Illustrations of the effect of track density and neutron exposure on detection of boron in metals and uranium in uranium ore for the NIA facility at the TRIGA Mark II reactor in Ljubljana and for LR 115 SSNTDs are given