fix chap4
This commit is contained in:
@@ -347,18 +347,18 @@ $n_{avg} = (0.3 \pm 0.02)A^{1/3}$~\cite{Singer.1974}.
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The neutron emission can be explained by several mechanisms:
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The neutron emission can be explained by several mechanisms:
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\begin{enumerate}
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\begin{enumerate}
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\item Direct emission follows reaction~\eqref{eq:mucap_proton}: these neutrons
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\item Direct emission follows reaction~\eqref{eq:mucap_proton}: these neutrons
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have fairly high energy, from a few \si{\mega\electronvolt}~to as high as 40--50
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have fairly high energy, from a few \si{\si{\MeV}}~to as high as 40--50
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\si{\mega\electronvolt}.
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\si{\si{\MeV}}.
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\item Indirect emission through an intermediate compound nucleus: the energy
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\item Indirect emission through an intermediate compound nucleus: the energy
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transferred to the neutron in the process~\eqref{eq:mucap_proton} is 5.2
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transferred to the neutron in the process~\eqref{eq:mucap_proton} is 5.2
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\si{\mega\electronvolt} if the initial proton is at rest, in nuclear
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\si{\si{\MeV}} if the initial proton is at rest, in nuclear
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environment, protons have a finite momentum distribution, therefore the
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environment, protons have a finite momentum distribution, therefore the
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mean excitation energy of the daughter nucleus is around 15 to 20
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mean excitation energy of the daughter nucleus is around 15 to 20
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\si{\mega\electronvolt}~\cite{Mukhopadhyay.1977}. This is above the nucleon
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\si{\si{\MeV}}~\cite{Mukhopadhyay.1977}. This is above the nucleon
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emission threshold in all complex nuclei, thus the daughter nucleus can
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emission threshold in all complex nuclei, thus the daughter nucleus can
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de-excite by emitting one or more neutrons. In some actinide nuclei, that
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de-excite by emitting one or more neutrons. In some actinide nuclei, that
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excitation energy might trigger fission reactions. The energy of indirect
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excitation energy might trigger fission reactions. The energy of indirect
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neutrons are mainly in the lower range $E_n \le 10$ \si{\mega\electronvolt}
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neutrons are mainly in the lower range $E_n \le 10$ \si{\si{\MeV}}
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with characteristically exponential shape of evaporation process. On top of
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with characteristically exponential shape of evaporation process. On top of
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that are prominent lines might appear where giant resonances occur.
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that are prominent lines might appear where giant resonances occur.
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\end{enumerate}
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\end{enumerate}
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@@ -382,7 +382,7 @@ data. There are two reasons for that:
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neutron emission. The rate is about 15\% for light nuclei and
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neutron emission. The rate is about 15\% for light nuclei and
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reduces to a few percent for medium and heavy nuclei.
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reduces to a few percent for medium and heavy nuclei.
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\item The charged particles are short ranged: the emitted protons,
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\item The charged particles are short ranged: the emitted protons,
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deuterons and alphas are typically low energy (2--20~\mega\electronvolt).
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deuterons and alphas are typically low energy ( \SIrange{2}{20}{\MeV}).
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But a relatively thick target is normally needed in order to achieve
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But a relatively thick target is normally needed in order to achieve
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a reasonable muon stopping rate and charged particle statistics. Therefore,
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a reasonable muon stopping rate and charged particle statistics. Therefore,
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emulsion technique is particularly powerful.
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emulsion technique is particularly powerful.
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@@ -411,9 +411,9 @@ statistics and in fair agreement with Morigana and Fry
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Protons with higher energy are technically easier to measure, but because of
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Protons with higher energy are technically easier to measure, but because of
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the much lower rate, they can only be studied at meson facilities. Krane and
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the much lower rate, they can only be studied at meson facilities. Krane and
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colleagues~\cite{KraneSharma.etal.1979} measured proton emission from
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colleagues~\cite{KraneSharma.etal.1979} measured proton emission from
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aluminium, copper and lead in the energy range above 40 \mega\electronvolt~and
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aluminium, copper and lead in the energy range above \SI{40}{\MeV} and
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found a consistent exponential shape in all targets. The integrated yields
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found a consistent exponential shape in all targets. The integrated yields
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above 40 \mega\electronvolt~are in the \sn{}{-4}--\sn{}{-3} range (see
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above \SI{40}{\MeV} are in the \sn{}{-4}--\sn{}{-3} range (see
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Table~\ref{tab:krane_proton_rate}), a minor contribution to total proton
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Table~\ref{tab:krane_proton_rate}), a minor contribution to total proton
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emission rate.
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emission rate.
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\begin{table}[htb]
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\begin{table}[htb]
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@@ -462,16 +462,16 @@ The aforementioned difficulties in charged particle measurements could be
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solved using an active target, just like nuclear emulsion. Sobottka and
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solved using an active target, just like nuclear emulsion. Sobottka and
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Wills~\cite{SobottkaWills.1968} took this approach when using a Si(Li) detector
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Wills~\cite{SobottkaWills.1968} took this approach when using a Si(Li) detector
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to stop muons. They obtained a spectrum of charged particles up to 26
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to stop muons. They obtained a spectrum of charged particles up to 26
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\mega\electronvolt~in Figure~\ref{fig:sobottka_spec}. The peak below 1.4
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\si{\MeV}~in Figure~\ref{fig:sobottka_spec}. The peak below 1.4
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\mega\electronvolt~is due to the recoiling $^{27}$Al. The higher energy events
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\si{\MeV}~is due to the recoiling $^{27}$Al. The higher energy events
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including protons, deuterons and alphas constitute $(15\pm 2)\%$ of capture
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including protons, deuterons and alphas constitute $(15\pm 2)\%$ of capture
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events, which is consistent with a rate of $(12.9\pm1.4)\%$ from gelatine
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events, which is consistent with a rate of $(12.9\pm1.4)\%$ from gelatine
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observed by Morigana and Fry. This part has an exponential
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observed by Morigana and Fry. This part has an exponential
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decay shape with a decay constant of 4.6 \mega\electronvolt. Measday
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decay shape with a decay constant of 4.6 \si{\MeV}. Measday
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noted~\cite{Measday.2001} the fractions of events in
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noted~\cite{Measday.2001} the fractions of events in
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the 26--32 \mega\electronvolt~range being 0.3\%, and above 32
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the 26--32 \si{\MeV}~range being 0.3\%, and above 32
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\mega\electronvolt~range being 0.15\%. This figure is in agreement with the
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\si{\MeV}~range being 0.15\%. This figure is in agreement with the
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integrated yield above 40 \mega\electronvolt~from Krane et al.
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integrated yield above 40 \si{\MeV}~from Krane et al.
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In principle, the active target technique could be applied to other material
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In principle, the active target technique could be applied to other material
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such as germanium, sodium iodine, caesium iodine, and other scintillation
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such as germanium, sodium iodine, caesium iodine, and other scintillation
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@@ -480,7 +480,7 @@ identification like in nuclear emulsion, the best one can achieve after all
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corrections is a sum of all charged particles. It should be noted here
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corrections is a sum of all charged particles. It should be noted here
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deuterons can contribute significantly, Budyashov et
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deuterons can contribute significantly, Budyashov et
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al.~\cite{BudyashovZinov.etal.1971} found deuteron components to be
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al.~\cite{BudyashovZinov.etal.1971} found deuteron components to be
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$(34\pm2)\%$ of the charged particle yield above 18 \mega\electronvolt~in
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$(34\pm2)\%$ of the charged particle yield above 18 \si{\MeV}~in
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silicon, and $(17\pm4)\%$ in copper.
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silicon, and $(17\pm4)\%$ in copper.
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\begin{figure}[htb]
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\begin{figure}[htb]
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\centering
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\centering
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@@ -547,7 +547,7 @@ protons were taken.
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Wyttenbach et al.\ saw that the cross section of each reaction decreases
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Wyttenbach et al.\ saw that the cross section of each reaction decreases
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exponentially with increasing Coulomb barrier. The decay constant for all
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exponentially with increasing Coulomb barrier. The decay constant for all
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$(\mu^-,\nu pxn)$ is about 1.5 per \mega\electronvolt~of Coulomb barrier. They
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$(\mu^-,\nu pxn)$ is about 1.5 per \si{\MeV}~of Coulomb barrier. They
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also commented a ratio for different de-excitation channels:
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also commented a ratio for different de-excitation channels:
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\begin{equation}
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\begin{equation}
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(\mu^-,\nu p):(\mu^-,\nu pn):(\mu^-,\nu p2n):(\mu^-,\nu p3n) = 1:6:4:4,
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(\mu^-,\nu p):(\mu^-,\nu pn):(\mu^-,\nu p2n):(\mu^-,\nu p3n) = 1:6:4:4,
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@@ -572,7 +572,7 @@ nucleus is formed, and then it releases energy by statistical emission of
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various particles. Three models for momentum distribution of protons in the
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various particles. Three models for momentum distribution of protons in the
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nucleus were used: (I) the Chew-Goldberger distribution
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nucleus were used: (I) the Chew-Goldberger distribution
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$\rho(p) \sim A/(B^2 + p^2)^2$; (II) Fermi gas at zero temperature; and (III)
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$\rho(p) \sim A/(B^2 + p^2)^2$; (II) Fermi gas at zero temperature; and (III)
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Fermi gas at a finite temperature ($kT = 9$ \mega\electronvolt).
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Fermi gas at a finite temperature ($kT = 9$ \si{\MeV}).
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A very good agreement with the experimental result for the alpha emission was
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A very good agreement with the experimental result for the alpha emission was
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obtained with distribution (III), both in the absolute percentage and the energy
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obtained with distribution (III), both in the absolute percentage and the energy
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@@ -598,7 +598,7 @@ the nucleon, the average excitation energy will increase, but the proton
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emission rate does not significantly improve and still could not explain the
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emission rate does not significantly improve and still could not explain the
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large discrepancy. He concluded that the evaporation mechanism can account
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large discrepancy. He concluded that the evaporation mechanism can account
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for only a small fraction of emitted protons. Moreover, the high energy protons
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for only a small fraction of emitted protons. Moreover, the high energy protons
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of 25--50 \mega\electronvolt~cannot be explained by the evaporation mechanism.
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of 25--50 \si{\MeV}~cannot be explained by the evaporation mechanism.
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He and Lifshitz~\cite{LifshitzSinger.1978, LifshitzSinger.1980} proposed two
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He and Lifshitz~\cite{LifshitzSinger.1978, LifshitzSinger.1980} proposed two
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major corrections to Ishii's model:
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major corrections to Ishii's model:
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\begin{enumerate}
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\begin{enumerate}
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@@ -611,14 +611,14 @@ major corrections to Ishii's model:
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is possibility for particles to escape from the nucleus.
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is possibility for particles to escape from the nucleus.
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\end{enumerate}
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\end{enumerate}
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With these improvements, the calculated proton spectrum agreed reasonably with
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With these improvements, the calculated proton spectrum agreed reasonably with
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data from Morigana and Fry in the energy range $E_p \le 30$ \mega\electronvolt.
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data from Morigana and Fry in the energy range $E_p \le 30$ \si{\MeV}.
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Lifshitz and Singer noted the pre-equilibrium emission is more important for
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Lifshitz and Singer noted the pre-equilibrium emission is more important for
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heavy nuclei. Its contribution in light nuclei is about a few percent,
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heavy nuclei. Its contribution in light nuclei is about a few percent,
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increasing to several tens of percent for $100<A<180$, then completely
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increasing to several tens of percent for $100<A<180$, then completely
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dominating in very heavy nuclei. This trend is also seen in other nuclear
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dominating in very heavy nuclei. This trend is also seen in other nuclear
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reactions at similar excitation energies. The pre-equilibrium emission also
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reactions at similar excitation energies. The pre-equilibrium emission also
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dominates the higher-energy part, although it falls short at energies higher
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dominates the higher-energy part, although it falls short at energies higher
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than 30 \mega\electronvolt. The comparison between the calculated proton
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than 30 \si{\MeV}. The comparison between the calculated proton
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spectrum and experimental data is shown in
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spectrum and experimental data is shown in
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Fig.~\ref{fig:lifshitzsinger_cal_proton}.
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Fig.~\ref{fig:lifshitzsinger_cal_proton}.
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\begin{figure}[htb]
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\begin{figure}[htb]
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@@ -670,7 +670,7 @@ higher than average, though not as high as Vil'gel'mora et
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al.~\cite{VilgelmovaEvseev.etal.1971} observed.
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al.~\cite{VilgelmovaEvseev.etal.1971} observed.
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For protons with higher energies in the range of
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For protons with higher energies in the range of
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40--90 \mega\electronvolt~observed in the emulsion data as well as in later
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40--90 \si{\MeV}~observed in the emulsion data as well as in later
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experiments~\cite{BudyashovZinov.etal.1971,BalandinGrebenyuk.etal.1978,
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experiments~\cite{BudyashovZinov.etal.1971,BalandinGrebenyuk.etal.1978,
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KraneSharma.etal.1979}, Lifshitz and Singer~\cite{LifshitzSinger.1988}
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KraneSharma.etal.1979}, Lifshitz and Singer~\cite{LifshitzSinger.1988}
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suggested another contribution from capturing on correlated two-nucleon
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suggested another contribution from capturing on correlated two-nucleon
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@@ -700,7 +700,7 @@ smaller in cases of Al and Cu, and about 10 times higher in case of AgBr
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\end{tabular}
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\end{tabular}
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\end{center}
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\end{center}
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\caption{Probability of proton emission with $E_p \ge 40$
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\caption{Probability of proton emission with $E_p \ge 40$
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\mega\electronvolt~as calculated by Lifshitz and
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\si{\MeV}~as calculated by Lifshitz and
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Singer~\cite{LifshitzSinger.1988} in comparison with available data.}
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Singer~\cite{LifshitzSinger.1988} in comparison with available data.}
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\label{tab:lifshitzsinger_cal_proton_rate_1988}
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\label{tab:lifshitzsinger_cal_proton_rate_1988}
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\end{table}
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\end{table}
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@@ -710,17 +710,17 @@ smaller in cases of Al and Cu, and about 10 times higher in case of AgBr
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\label{sub:summary_on_proton_emission_from_aluminium}
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\label{sub:summary_on_proton_emission_from_aluminium}
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There is no direct measurement of proton emission following
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There is no direct measurement of proton emission following
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muon capture in the relevant energy for the COMET Phase-I of 2.5--10
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muon capture in the relevant energy for the COMET Phase-I of 2.5--10
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\mega\electronvolt:
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\si{\MeV}:
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\begin{enumerate}
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\begin{enumerate}
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\item Spectrum wise, only one energy spectrum (Figure~\ref{fig:krane_proton_spec})
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\item Spectrum wise, only one energy spectrum (Figure~\ref{fig:krane_proton_spec})
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for energies above 40 \mega\electronvolt~is available from Krane et
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for energies above 40 \si{\MeV}~is available from Krane et
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al.~\cite{KraneSharma.etal.1979},
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al.~\cite{KraneSharma.etal.1979},
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where an exponential decay shape with a decay constant of
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where an exponential decay shape with a decay constant of
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$7.5 \pm 0.4$~\mega\electronvolt. At low energy range, the best one can get is
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$7.5 \pm 0.4$~\si{\MeV}. At low energy range, the best one can get is
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the charged particle spectrum, which includes protons, deuterons and alphas,
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the charged particle spectrum, which includes protons, deuterons and alphas,
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from the neighbouring element silicon (Figure~\ref{fig:sobottka_spec}).
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from the neighbouring element silicon (Figure~\ref{fig:sobottka_spec}).
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This charged particle spectrum peaks around 2.5 \mega\electronvolt~and
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This charged particle spectrum peaks around 2.5 \si{\MeV}~and
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reduces exponentially with a decay constant of 4.6 \mega\electronvolt.
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reduces exponentially with a decay constant of 4.6 \si{\MeV}.
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\item The activation data from Wyttenbach et
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\item The activation data from Wyttenbach et
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al.~\cite{WyttenbachBaertschi.etal.1978} only gives rate of
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al.~\cite{WyttenbachBaertschi.etal.1978} only gives rate of
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$^{27}\textrm{Al}(\mu^-,\nu pn)^{25}\textrm{Na}$ reaction, and set a lower
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$^{27}\textrm{Al}(\mu^-,\nu pn)^{25}\textrm{Na}$ reaction, and set a lower
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@@ -748,9 +748,9 @@ A spectrum shape at this energy range is not available.
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\label{sub:motivation_of_the_alcap_experiment}
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\label{sub:motivation_of_the_alcap_experiment}
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As mentioned, protons from muon capture on aluminium might cause a very high
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As mentioned, protons from muon capture on aluminium might cause a very high
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rate in the COMET Phase-I CDC. The detector is designed to accept particles
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rate in the COMET Phase-I CDC. The detector is designed to accept particles
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with momenta in the range of 75--120 \mega\electronvolt\per\cc.
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with momenta in the range of 75--120 \si{\MeV\per\cc}.
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Figure~\ref{fig:proton_impact_CDC} shows that protons with kinetic energies of
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Figure~\ref{fig:proton_impact_CDC} shows that protons with kinetic energies of
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2.5--8 \mega\electronvolt~will hit the CDC. Such events are troublesome due to
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2.5--8 \si{\MeV}~will hit the CDC. Such events are troublesome due to
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their large energy deposition. Deuterons and alphas at that momentum range is
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their large energy deposition. Deuterons and alphas at that momentum range is
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not of concern because they have lower kinetic energy and higher stopping
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not of concern because they have lower kinetic energy and higher stopping
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power, thus are harder to escape the muon stopping target.
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power, thus are harder to escape the muon stopping target.
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@@ -758,9 +758,9 @@ power, thus are harder to escape the muon stopping target.
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\centering
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\centering
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\includegraphics[width=0.85\textwidth]{figs/proton_impact_CDC}
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\includegraphics[width=0.85\textwidth]{figs/proton_impact_CDC}
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\caption{Momentum-kinetic energy relation of protons, deuterons and alphas
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\caption{Momentum-kinetic energy relation of protons, deuterons and alphas
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below 10\mega\electronvolt. Shaded area is the acceptance of the COMET
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below 10\si{\MeV}. Shaded area is the acceptance of the COMET
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Phase-I's CDC. Protons with energies in the range of 2.5--8
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Phase-I's CDC. Protons with energies in the range of 2.5--8
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\mega\electronvolt~are in the acceptance of the CDC. Deuterons and alphas at
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\si{\MeV}~are in the acceptance of the CDC. Deuterons and alphas at
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low energies should be stopped inside the muon stopping target.}
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low energies should be stopped inside the muon stopping target.}
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\label{fig:proton_impact_CDC}
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\label{fig:proton_impact_CDC}
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\end{figure}
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\end{figure}
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@@ -793,10 +793,10 @@ function given by:
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where $T$ is the kinetic energy of the proton, and the fitted parameters are
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where $T$ is the kinetic energy of the proton, and the fitted parameters are
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$A=0.105\textrm{ MeV}^{-1}$, $T_{th} = 1.4\textrm{ MeV}$, $\alpha = 1.328$ and
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$A=0.105\textrm{ MeV}^{-1}$, $T_{th} = 1.4\textrm{ MeV}$, $\alpha = 1.328$ and
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$T_0 = 3.1\textrm{ MeV}$. The baseline
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$T_0 = 3.1\textrm{ MeV}$. The baseline
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design of the absorber is 1.0 \milli\meter~thick
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design of the absorber is 1.0 \si{\mm}~thick
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carbon-fibre-reinforced-polymer (CFRP) which contributes
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carbon-fibre-reinforced-polymer (CFRP) which contributes
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195~\kilo\electronvolt\per\cc~to the momentum resolution. The absorber also
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195~\si{\keV\per\cc}~to the momentum resolution. The absorber also
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down shifts the conversion peak by 0.7 \mega\electronvolt. This is an issue as
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down shifts the conversion peak by 0.7 \si{\MeV}. This is an issue as
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it pushes the signal closer to the DIO background region. For those reasons,
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it pushes the signal closer to the DIO background region. For those reasons,
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a measurement of the rate and spectrum of proton emission after muon capture is
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a measurement of the rate and spectrum of proton emission after muon capture is
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required in order to optimise the CDC design.
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required in order to optimise the CDC design.
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@@ -804,41 +804,40 @@ required in order to optimise the CDC design.
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\subsection{Experimental method for proton measurement}
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\subsection{Experimental method for proton measurement}
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\label{sub:experimental_method}
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\label{sub:experimental_method}
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We planned to use a low energy, narrow momentum spread available at PSI to
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We planned to use a low-energy, narrow-momentum-spread available at PSI to
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fight the aforementioned difficulties in measuring protons. The beam momentum
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fight the aforementioned difficulties in measuring protons. The beam momentum
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is tunable from 28 to 45~\mega\electronvolt\ so that targets at different
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is tunable from \SIrange{28}{45}{\MeV} so that targets at different
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thickness from 25 to 100 \micro\meter\ can be studied. The $\pi$E1 beam line
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thickness from \SIrange{25}{100}{\um} can be studied. The $\pi$E1 beam line
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could provide about \sn{}{3} muons\per\second\ at 1\% momentum spread, and
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could deliver \sn{}{3} muons/\si{\s} at 1\% momentum spread, and
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\sn{}{4} muons\per\second\ at 3\% momentum spread. With this tunable beam, the
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\sn{}{4} muons/\si{\s} at 3\% momentum spread. The muon stopping distribution
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stopping distribution of the muons is well-defined.
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of the muons could be well-identified using this excellent beam.
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The principle of the particle identification used in the AlCap experiment is
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Emitting charged particles from nuclear muon capture will be identified by the
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that for each species, the function describes the relationship between energy
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specific energy loss. The specific energy loss is calculated as energy loss
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loss per unit length (dE/dx) and the particle energy E is uniquely defined.
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per unit path length \sdEdx at a certain energy $E$. The quantity is uniquely
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With a simple system of two detectors, dE/dx can be obtained by
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defined for each particle species.
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measuring energy deposit $\Delta$E in one detector of known thickness
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$\Delta$x, and E is the sum of energy deposit in both detector if the particle
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is fully stopped.
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In the AlCap, we realise the idea with a pair of silicon detectors: one thin
|
The specific energy loss is measured in the AlCap using a pair of silicon
|
||||||
detector of 65~\micron\ serves as the $\Delta$E counter, and one thick detector
|
detectors: a \SI{65}{\um}-thick detector, and a \SI{1500}{\um}-thick detector.
|
||||||
of 1500~\micron\ that can fully stop protons up to about 12~MeV. Since the
|
Each detector is $5\times5$ \si{\cm^2} in area.
|
||||||
$\Delta \textrm{d}=65$~\micron\ is known, the function relates dE/dx to
|
The thinner one provides $\mathop{dE}$ information, while the sum energy
|
||||||
E reduces to a function between $\Delta$E and E. Figure~\ref{fig:pid_sim} shows
|
deposition in the two gives $E$, if the particle is fully stopped. The silicon
|
||||||
that the function of protons can be clearly distinguished from other charged
|
detectors pair could help distinguish protons from other charged particles from
|
||||||
particles in the energy range of interest.
|
\SIrange{2.5}{12}{\MeV} as shown in \cref{fig:pid_sim}.
|
||||||
\begin{figure}[htbp]
|
\begin{figure}[htbp]
|
||||||
\centering
|
\centering
|
||||||
\includegraphics[width=0.75\textwidth]{figs/pid_sim}
|
\includegraphics[width=0.75\textwidth]{figs/pid_sim}
|
||||||
\caption{Simulation study of PID using a pair of silicon detectors}
|
\caption{Simulation study of PID using a pair of silicon detectors. The
|
||||||
|
detector resolutions follow the calibration results provided by the
|
||||||
|
manufacturer.}
|
||||||
\label{fig:pid_sim}
|
\label{fig:pid_sim}
|
||||||
\end{figure}
|
\end{figure}
|
||||||
|
|
||||||
The AlCap uses two pairs of detector with large area, placed symmetrically with
|
Two pairs of detectors, placed symmetrically with
|
||||||
respect to the target provide a mean to check for muon stopping distribution.
|
respect to the target, provide a mean to check for muon stopping distribution
|
||||||
The absolute number of stopped muons are inferred
|
inside the target. The absolute number of stopped muons is calculated
|
||||||
from the number of muonic X-rays recorded by a germanium detector. For
|
from the number of muonic X-rays recorded by a germanium detector. For
|
||||||
aluminium, the $(2p-1s)$ line is at 346 \kilo\electronvolt. The acceptances of
|
aluminium, the $(2p-1s)$ line is at \SI{346.828}{\keV}. The acceptances of
|
||||||
detectors will be assessed by detailed Monte Carlo study using Geant4.
|
detectors will be assessed by detailed Monte Carlo study using Geant4.
|
||||||
|
|
||||||
% subsection experimental_method (end)
|
% subsection experimental_method (end)
|
||||||
@@ -855,7 +854,7 @@ Particle Emission after Muon Capture.}\\ Protons emitted after nuclear muon
|
|||||||
capture in the stopping target dominate the single-hit rates in the tracking
|
capture in the stopping target dominate the single-hit rates in the tracking
|
||||||
chambers for both the Mu2e and COMET Phase-I experiments. We plan to measure
|
chambers for both the Mu2e and COMET Phase-I experiments. We plan to measure
|
||||||
both the total rate and the energy spectrum to a precision of 5\% down to
|
both the total rate and the energy spectrum to a precision of 5\% down to
|
||||||
proton energies of 2.5 MeV.
|
proton energies of \SI{2.5}{\MeV}.
|
||||||
\item[WP2:] (Lynn(PNNL), Miller(BU))
|
\item[WP2:] (Lynn(PNNL), Miller(BU))
|
||||||
\textbf{Gamma and X-ray Emission after Muon Capture.}\\ A Ge detector will
|
\textbf{Gamma and X-ray Emission after Muon Capture.}\\ A Ge detector will
|
||||||
be used to measure X-rays from the muonic atomic cascade, in order to provide
|
be used to measure X-rays from the muonic atomic cascade, in order to provide
|
||||||
@@ -884,7 +883,7 @@ than 1 MeV up to 10 MeV. \\
|
|||||||
\end{itemize}
|
\end{itemize}
|
||||||
|
|
||||||
WP1 is the most developed
|
WP1 is the most developed
|
||||||
project in this program. Most of the associated apparatus has been built and
|
project in this program with most of the associated apparatus has been built and
|
||||||
optimized. We are ready to start this experiment in 2013, while preparing and
|
optimized. We are ready to start this experiment in 2013, while preparing and
|
||||||
completing test measurements and simulations to undertake WP2 and WP3.
|
completing test measurements and simulations to undertake WP2 and WP3.
|
||||||
|
|
||||||
|
|||||||
@@ -50,6 +50,9 @@ $\mu^- \rightarrow e^- \nu_\mu \overline{\nu}_e e^+ e^-$\xspace
|
|||||||
|
|
||||||
\newcommand{\cc}{$c$\xspace}
|
\newcommand{\cc}{$c$\xspace}
|
||||||
|
|
||||||
|
\newcommand{\dEdx}{$\dfrac{\mathop{dE}}{\mathop{dx}}$\xspace}
|
||||||
|
\newcommand{\sdEdx}{$\sfrac{\mathop{dE}}{\mathop{dx}}$\xspace}
|
||||||
|
|
||||||
\newcommand{\rootana}{{\ttfamily rootana}}
|
\newcommand{\rootana}{{\ttfamily rootana}}
|
||||||
\newcommand{\alcapana}{{\ttfamily alcapana}}
|
\newcommand{\alcapana}{{\ttfamily alcapana}}
|
||||||
\newcommand{\tpulseisland}{{\ttfamily TPulseIsland}}
|
\newcommand{\tpulseisland}{{\ttfamily TPulseIsland}}
|
||||||
|
|||||||
@@ -32,8 +32,8 @@ for the COMET experiment}
|
|||||||
%\input{chapters/chap1_intro}
|
%\input{chapters/chap1_intro}
|
||||||
%\input{chapters/chap2_mu_e_conv}
|
%\input{chapters/chap2_mu_e_conv}
|
||||||
%\input{chapters/chap3_comet}
|
%\input{chapters/chap3_comet}
|
||||||
%\input{chapters/chap4_alcap_phys}
|
\input{chapters/chap4_alcap_phys}
|
||||||
%\input{chapters/chap5_alcap_setup}
|
\input{chapters/chap5_alcap_setup}
|
||||||
\input{chapters/chap6_analysis}
|
\input{chapters/chap6_analysis}
|
||||||
%\input{chapters/chap7_results}
|
%\input{chapters/chap7_results}
|
||||||
|
|
||||||
|
|||||||
Reference in New Issue
Block a user