An analytical representation of the response of the NaI(Tl) detector for the gamma-ray spectrum analysis

An analytical function for describing the response function of γ-rays from the NaI(Tl) detector was constructed with the purpose of establishing the method of automatic γ-ray spectrum analysis. The response was found to be divided into six portions; the function of each portion joins smoothly to the one representing the adjacent part. Empirical equations for the parameters specifying the response function were found as functions of the γ-ray energy in relation to the detector dimension. The obtained response function was fitted to the observed spectrum by the least squares method. The calculated spectrum agreed well with the observed one. (author)