Recent Developments in Scintillation Spectrometry

The most important area of development in gamma-ray scintillation spectrometry at the present time is the adaptation of digital computer techniques to the analysis of pulse-height spectra. The use of multi-dimensional pulse analyzers capable of storing 256 spectra, each containing up to 256 channels of digital information, has greatly increased the need for automated data processing techniques. As a first step, logical adders and tape input-output systems have been added to modern analyzers to permit some reduction of data within the machine itself. The development of analytical techniques adaptable to machine programming, however, appears to represent the only reasonable solution of the problem. A series of computer programs are described which have been successfully applied to the reduction of pulse-height data using digital computers. The calculations carried out by these programs include: determination of pulse-height vs energy response of a NaI detector; calculation of coincidence sum spectra; and the analysis of complex pulse-height spectra to obtain energies and relative intensities of individual gamma rays or relative abundances from a mixture of radionuclides. Measurement problems and instrumental requirements are discussed in detail.