Title: | A comparison of different theoretical models of positron lifetime spectra for polymers |
Authors: | Kansy, Jerzy |
Keywords: | anihilacja pozytonów; polimery |
Issue Date: | 2008 |
Citation: | Acta Physica Polonica A, Vol. 113, nr 5 (2008), s. 1397-1407 |
Abstract: | The same reference positron lifetime spectra of polyurethane, measured in temperature range 112 to 390 K, were analyzed with three theoretical models: the \conventional" model with three exponential decay component
of discrete values of lifetimes, a model with one discrete exponential component and two \packages" of exponentials with log-normal distribution of annihilation rates, and a model considering positronium slow localization, positronium internal relaxation as well as \delayed" formation of positronium. It turns out that the two latter models fit the experimental data with the same excellent quality, in spite of the fact that in both models the
ratio of intensities related to para-positronium and ortho-positronium was constrained to be as 1:3. |
URI: | http://hdl.handle.net/20.500.12128/8320 |
ISSN: | 0587-4246 |
Appears in Collections: | Artykuły (WNŚiT)
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