Multichannel Pulse Analysis Chapter 18 Multichannel Pulse Analysis GK Lec-No-35-37 Copyright © 2014 John Wiley & Sons, Inc. All rights reserved. 1

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Ch-18-V. SPECTRUM ANALYSIS-C. Analysis of Spectra with Peaks -GK-53 Although in principle it is possible to use general unfolding procedures for gamma-ray spectra,33 a full deconvolution of the spectrum is seldom carried out. One reason is that the response functions for scintillators or germanium detectors are quite complicated, and uncertainties quickly propagate over the entire spectrum. A more important reason, however, is that a full deconvolution is usually unnecessary. Gamma-ray spectra almost always consist of a number of discrete gamma-ray energies, and the response functions show a predominant peak. One would therefore expect a corresponding peak in the pulse height spectrum for every discrete energy in the incident radiation that can be resolved, and the spectrum analysis can consist of simply locating and quantifying these peaks. If continuous gamma-ray spectra are involved, individual peaks will not appear in the recorded spectrum and there is no recourse but to carry out a full deconvolution. Computer programs are continually being developed and improved for the automatic localization and quantification of peaks in multichannel spectra. Many are available as commercial packages supplied through the vendors of multichannel analysis equipment. Others are available as public domain software. Reviews of some of these programs as applied to germanium detector spectra t can be found in Refs. 34-36, and an intercomparison of their performance with test spectra is published in Ref. 37. Two representative examples (SAMPO and GAUSS) are described in Refs. 38 and 39. The programs serve two main purposes: (1) to locate the centroid position of all statistically significant peaks appearing in the spectrum and (2) to determine the net area under each peak that lies above the continuum or background on which the peak is superimposed.. © 2014 John Wiley & Sons, Inc. All rights reserved.

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