1 | \section{Complementary parameterised and theoretical treatment} |
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2 | |
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3 | Absorption of negative pions and kaons at rest from a nucleus |
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4 | is described in literature |
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5 | \cite{Gadioli}, \cite{Chiang}, \cite{Ashery}, \cite{Weyer} |
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6 | as consisting of two main components: |
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7 | \begin{itemize} |
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8 | \item a primary absorption process, involving the interaction of the |
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9 | incident stopped hadron with one or more nucleons of the target nucleus; |
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10 | \item the deexcitation of the remnant nucleus, left in an excitated |
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11 | state as a result of the occurrence of the primary absorption process. |
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12 | \end{itemize} |
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13 | |
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14 | This interpretation is supported by several experiments |
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15 | \cite{Hartmann}, \cite{Madley}, \cite{Schleputz}, \cite{Orth}, |
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16 | \cite{Pruys}, \cite{Heusi}, \cite{Isaak}, |
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17 | that have measured various features characterizing these processes. |
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18 | In many cases |
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19 | the experimental measurements are capable to distinguish the final |
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20 | products originating from the primary absorption process and those |
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21 | resulting from the nuclear deexcitation component. |
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22 | |
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23 | A set of stopped particle absorption processes is implemented in GEANT4, |
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24 | based on this two-component model (PiMinusAbsorptionAtRest and |
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25 | KaonMinusAbsorptionAtRest classes, for $\pi^{-}$ and $K^{-}$ respectively. |
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26 | Both implementations adopt the same approach: |
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27 | the primary absorption component of the process is parameterised, |
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28 | based on available experimental data; |
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29 | the nuclear deexcitation component is handled through the theoretical models |
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30 | described elsewhere in this Manual. |
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31 | |
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