SpectrumSearch: Automatical identification of the peaks in spectrum with the presence of the continuous background and statistical fluctuations - noise

Description

This function searches for peaks in source spectrum It is based on deconvolution method. First the background is removed (if desired), then Markov spectrum is calculated (if desired), then the response function is generated according to given sigma and deconvolution is carried out.

Usage

SpectrumSearch(y,sigma=3.0,threshold=10.0,background=FALSE,
               iterations=13,markov=FALSE,window=3)

Arguments

numeric vector of source spectrum

sigma

sigma of searched peaks

threshold

threshold value in % for selected peaks, peaks with amplitude less than threshold*highest_peak/100 are ignored

background

Remove background. Logical variable, set to TRUE if the removal of background before deconvolution is desired

iterations

number of iterations in deconvolution operation

markov

logical variable, if it is TRUE, first the source spectrum is replaced by new spectrum calculated using Markov chains method.

window

averanging window of searched peaks, applies only for Markov smoothing

Value

List with two vectors:
yDeconvoluted source vector
posIndexes of found peaks in y spectrum

encoding

latin1

Details

Algorithm is straightforward. The function removes background and smooths (if requested) source vector y, then deconvolves it using Gaussian with sigma as responce vector and after that searches for peaks in deconvoluted vector which are above threshold.

References

M.A. Mariscotti: A method for identification of peaks in the presence of background and its application to spectrum analysis. NIM 50 (1967), 309-320.

M. Morh�c, J. Kliman, V. Matousek, M. Veselsk�, I. Turzo.:Identification of peaks in multidimensional coincidence gamma-ray spectra. NIM, A443 (2000) 108-125. Z.K. Silagadze, A new algorithm for automatic photopeak searches. NIM A 376 (1996), 451.