Choice of the best region for channel-by-channel summation of estimating the intensity of single photopeaks

The influence of partial peak width integration on the statistical error has been investigated. It has been shown that integration of the central photopeak part —±(0.55–0.64) FWHM for narrow peaks and ±(0.50–0.53) FWHM for wide peaks-allows to decrease the statistical error 1.5–2.0 times in comparision with the TPA method. The results obtained are valid both for real photopeaks and for smoothed spectra. The theoretical results have been confirmed by experimental data.