1 | % GEANT4 Physics Reference Manual - Scintillation Process |
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2 | % in LaTex 2e - by P. Gumplinger |
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3 | |
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4 | %\documentclass[11pt,twoside,a4page]{article} |
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5 | %\usepackage{epsfig} |
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6 | |
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7 | %\setlength{\parindent}{0pt} |
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8 | |
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9 | %\begin{document} |
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10 | |
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11 | %\title{Scintillation} |
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12 | %\author{P.~Gumplinger} |
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13 | %\date{December 7, 1998} |
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14 | %\maketitle |
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15 | |
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16 | \section{Scintillation} |
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17 | |
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18 | Every scintillating material has a characteristic light yield, $Y\, |
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19 | (photons/MeV$), and an intrinsic resolution which generally broadens |
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20 | the statistical distribution, $\sigma_i/\sigma_s > 1$, due to impurities |
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21 | which are typical for doped crystals like NaI(Tl) and CsI(Tl). The |
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22 | average yield can have a non-linear dependence on the local energy |
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23 | deposition. Scintillators also have a time distribution spectrum with |
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24 | one or more exponential decay time constants, $\tau_{i}$, with each |
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25 | decay component having its intrinsic photon emission spectrum. These are |
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26 | empirical parameters typical for each material. \\ |
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27 | |
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28 | \noindent |
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29 | The generation of scintillation light can be simulated by sampling the |
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30 | number of photons from a Poisson distribution. This distribution is based |
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31 | on the energy lost during a step in a material and on the scintillation |
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32 | properties of that material. The frequency of each photon is sampled from |
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33 | the empirical spectra. The photons are generated evenly along the track |
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34 | segment and are emitted uniformly into $4\pi$ with a random linear |
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35 | polarization. |
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36 | |
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37 | \subsection{Status of this document} |
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38 | 07.12.98 created by P.Gumplinger |
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39 | |
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40 | %\end{document} |
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