A computer method of γ-ray spectra stabilization

A numerical method for correction of shift and gain instability in γ-spectroscopy has been developed. It is proposed to apply the correction to partial spectra obtained for a short counting time. The resulting spectrum is then obtained by summing up the partial spectra. The procedure does not change the peak parameters, such as peak area and the full-width-at-half-maximum (FWHM). The changes in the position of two reference peaks are used for correction. To test the method, two spectra were shifted by 0.5 channel: a standard spectrum obtained from the IAEA in Vienna and a spectrum of neutron activated geological sample. The changes in peak area and FWHM after such shifting are much smaller than their relative standard deviations. The spectra were also modified by changing the gain. The obtained results were similar to those obtained by shifting.