SpectrumSearch {Peaks} | R Documentation |
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.
SpectrumSearch(y,sigma=3.0,threshold=10.0,background=FALSE, iterations=13,markov=FALSE,window=3)
y |
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 |
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
.
List with two vectors:
y |
Deconvoluted source vector |
pos |
Indexes of found peaks in y spectrum |
Miroslav Morhác
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. Morhác, J. Kliman, V. Matousek, M. Veselský, 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.
SpectrumSmoothMarkov
,
SpectrumBackground
, SpectrumDeconvolution