Spectrum Analysis Program Research Articles

Automatic interpretation of gamma-ray data obtained in non-destructive activation analysis

The procedure in use at our institute for the extraction of the desired element concentrations in a sample from the peak data obtained by a spectrum analysis program, is described in detail. The method is based on the use of zinc as a single comparator and takes into consideration primary activation products as well as their daughter isotopes. After assigning isotopes to spectrum peaks on the basis of γ-ray energies, the list of possible isotopes is reduced to a list of present isotopes with their concentrations using criteria based on half life, specificity and intensity of γ-rays. For elements not observed, detection limits are estimated. The procedure has been used extensively during the last two years and has shown to produce reliable results.

A new peak search method for an automatic spectrum analysis program

A new method for the automatic identification of peaks in a spectrum has been devised. A region centred on each channel i of the spectrum is fitted by a peak of given shape superimposed on a constant background. A maximum as a function of i in the height of the fitted peak is used to indicate the presence of a peak in the spectrum. Close-lying doublets and triplets that are not resolved by other methods can be found using this method. The sensitivity of the method to small peaks and to fluctuations in the background has been investigated. Together with a least-squares peak fitting routine using the Marquardt algorithm, the peak search subroutine forms an automatic spectrum analysis program, which has been used extensively for the analysis of charged particle and γ-ray spectra. The peak shape used for these spectra consists of a Gaussian in the top, an exponential on the right-hand side and a double exponential on the left-hand side. Several examples of analysed spectra used for a test of the search and fitting methods are presented together with a discussion of the errors in the fitted parameters.

A Versatile Data Processing System for Nuclear Gamma-Rays Spectroscopy with a Minicomputer

A versatile data-processing system using a mini-computer USC-3 has been developed for nuclear gamma-ray spectroscopy with Ge(Li) detectors. In order to perform data analyses in a conversation mode more easily and rapidly a light-pen system was constructed and connected to the USC-3 computer. The light-pen system made with a photo-diode and TTL digital IC's was designed so as to be applicable to any computer-aided pulse-height analysis system. The gamma-ray spectrum data are analyzed with the aid of the light-pen system and software programs in the assembler language. The spectrum analysis programs mainly consist of the smoothing of the original data, the automatic search for peaks in the spectrum and the evaluation of the peak positions and areas after background subtraction. The design principle and the circuits of the light-pen system and softwares for spectrum analyses are described.

Computer methods in analytical mass spectrometry. Development of programs for analysis of low-resolution mass spectra

Computer methods in analytical mass spectrometry. Development of programs for analysis of low-resolution mass spectra

Mesure de l'énergie des rayonnements gamma du césium 138

Ge(Li) gamma spectrometry is used to determine gamma-ray energies and intensities of fission products. Experimental devices are shown: reactor loop, electronics, programs for analysis of spectra. Gamma energies and relative gamma intensities of 138Cs are measured. The principal photopeaks are: 1435.9±0.2 keV, 462.8±0.1 keV and 1009.8±0.2 keV.