tried various font settings, go back to the default one
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@@ -3,7 +3,7 @@
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\section{Analysis modules}
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\section{Analysis modules}
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\label{sec:analysis_modules}
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\label{sec:analysis_modules}
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A full offline analysis has not been completed yet, but initial analysis
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A full analysis has not been completed yet, but initial analysis
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based on the existing modules (Table~\ref{tab:offline_modules}) is possible
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based on the existing modules (Table~\ref{tab:offline_modules}) is possible
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thanks to the modularity of the analysis framework.
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thanks to the modularity of the analysis framework.
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@@ -57,14 +57,14 @@ Figure~\ref{fig:tap_maxbin_bad}.
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The TSimpleMuonEvent first picks a muon candidate, then loops through all
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The TSimpleMuonEvent first picks a muon candidate, then loops through all
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pulses on all detector channels, and picks all pulses occur in
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pulses on all detector channels, and picks all pulses occur in
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a time window of $\pm 10$~\micro\second\ around each candidate to build a muon
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a time window of \SI{\pm 10}{\si{\micro\second}} around each candidate to build
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event. A muon candidates is a hit on the upstream plastic scintillator with
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a muon event. A muon candidates is a hit on the upstream plastic scintillator
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an amplitude higher than a threshold which was chosen to reject minimum ionising
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with an amplitude higher than a threshold which was chosen to reject minimum
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particles (MIPs). The
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ionising particles (MIPs). The period of \SI{10}{\si{\micro\second}} is long
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10~\micro\second\ is long enough compares to the mean life time of muons in the
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enough compares to the mean life time of muons in the target materials
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target materials (0.758~\micro\second\ for silicon, and 0.864~\micro\second\ for
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(\SI{0.758}{\si{\micro\second}} for silicon, and \SI{0.864}{\si{\micro\second}}
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aluminium~\cite{SuzukiMeasday.etal.1987}) so practically all of emitted charged
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for aluminium~\cite{SuzukiMeasday.etal.1987}) so practically all of emitted
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particles would be recorded in this time window.
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charged particles would be recorded in this time window.
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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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%\includegraphics[width=0.85\textwidth]{figs/tme_musc_threshold}
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%\includegraphics[width=0.85\textwidth]{figs/tme_musc_threshold}
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@@ -73,13 +73,13 @@ particles would be recorded in this time window.
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%\end{figure}
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%\end{figure}
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A pile-up protection mechanism is employed to reject multiple muons events: if
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A pile-up protection mechanism is employed to reject multiple muons events: if
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there exists another muon hit in less than 15~\micro\second\ from the candidate
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there exists another muon hit in less than \SI{15}{\si{\micro\second}} from the
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then both the candidate and the other muon are discarded. This pile-up
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candidate then both the candidate and the other muon are discarded. This
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protection would cut out less than 11\% total number of events because the beam
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pile-up protection would cut out less than 11\% total number of events because
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rate was generally less than 8~\kilo\hertz.
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the beam rate was generally less than \SI{8}{\kilo\hertz}.
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%In runs with active silicon targets, another requirement is applied for the
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%In runs with active silicon targets, another requirement is applied for the
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%candidate: a prompt hit on the target in $\pm 200$ \nano\second\ around the
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%candidate: a prompt hit on the target in $\pm 200$ \si{\nano\second}\ around the
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%time of the $\mu$Sc pulse. The number comes from the observation of the
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%time of the $\mu$Sc pulse. The number comes from the observation of the
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%time correlation between hits on the target and the $\mu$Sc
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%time correlation between hits on the target and the $\mu$Sc
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%(Figure~\ref{fig:tme_sir_prompt_rational}).
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%(Figure~\ref{fig:tme_sir_prompt_rational}).
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@@ -120,11 +120,12 @@ shown in Figure~\ref{fig:lldq}.
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The energy calibration for the silicon detectors were done routinely during the
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The energy calibration for the silicon detectors were done routinely during the
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run, mainly by an
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run, mainly by an
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$^{241}\textrm{Am}$ alpha source and a tail pulse generator. The source emits
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$^{241}\textrm{Am}$ alpha source and a tail pulse generator. The source emits
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79.5 $\alpha\per\second$ in a 2$\pi$~\steradian~solid angle. The most
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79.5 $\alpha$\si{\per\second} in a \SI{2\pi}{\steradian} solid angle. The most
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prominent alpha particles have energies of 5.484~\mega\electronvolt\
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prominent alpha particles have energies of \SI{5.484}{\si{\mega\electronvolt}}
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(85.2\%) and 5.442~\mega\electronvolt\ (12.5\%). A tail pulse with amplitude of
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(85.2\%) and \SI{5.442}{\si{\mega\electronvolt}} (12.5\%). A tail pulse with
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66 \milli\volt~was used to simulate the response of the silicon detectors'
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amplitude of
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preamplifiers to a particle with 1\mega\electronvolt~energy deposition.
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\SI{66}{\milli\volt}~was used to simulate the response of the silicon detectors'
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preamplifiers to a particle with \SI{1}{\si{\mega\electronvolt}} energy deposition.
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During data taking period, electrons in the beam were were also used for energy
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During data taking period, electrons in the beam were were also used for energy
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calibration of thick silicon detectors where energy deposition is large enough.
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calibration of thick silicon detectors where energy deposition is large enough.
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@@ -136,14 +137,14 @@ tuning period.
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According to Micron Semiconductor
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According to Micron Semiconductor
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\footnote{\url{http://www.micronsemiconductor.co.uk/}}, the
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\footnote{\url{http://www.micronsemiconductor.co.uk/}}, the
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manufacturer of the silicon detectors, the nominal thickness of the dead layer on
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manufacturer of the silicon detectors, the nominal thickness of the dead layer on
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each side is 0.5~\micron. The alpha particles from the source would deposit
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each side is 0.5~\si{\micro\meter}. The alpha particles from the source would deposit
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about 66~keV in this layer, and the peak would appear at 5418~keV
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about 66~keV in this layer, and the peak would appear at 5418~keV
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(Figure~\ref{fig:toyMC_alpha}).
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(Figure~\ref{fig:toyMC_alpha}).
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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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\includegraphics[width=0.6\textwidth]{figs/toyMC_alpha}
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\includegraphics[width=0.6\textwidth]{figs/toyMC_alpha}
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\caption{Energy loss of the alpha particles after a dead layer of
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\caption{Energy loss of the alpha particles after a dead layer of
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0.5~\micron.}
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0.5~\si{\micro\meter}.}
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\label{fig:toyMC_alpha}
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\label{fig:toyMC_alpha}
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\end{figure}
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\end{figure}
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@@ -190,18 +191,18 @@ found to be:
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\textrm{ E [keV]} = 0.1219 \times \textrm{ADC} + 1.1621
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\textrm{ E [keV]} = 0.1219 \times \textrm{ADC} + 1.1621
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\end{equation}
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\end{equation}
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The energy resolution (full width at half maximum) was better than
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The energy resolution (full width at half maximum) was better than
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2.6~\kilo\electronvolt\ for all the $^{152}\textrm{Eu}$ peaks. It was a little
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2.6~\si{\kilo\electronvolt}\ for all the $^{152}\textrm{Eu}$ peaks. It was a little
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worse at 3.1~\kilo\electronvolt~for the annihilation photons at
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worse at 3.1~\si{\kilo\electronvolt}~for the annihilation photons at
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511.0~\kilo\electronvolt.
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511.0~\si{\kilo\electronvolt}.
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The absolute efficiencies for the $(2p-1s)$ lines of aluminium
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The absolute efficiencies for the $(2p-1s)$ lines of aluminium
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(346.828~\kilo\electronvolt) and silicon (400.177~\kilo\electronvolt) are
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(346.828~\si{\kilo\electronvolt}) and silicon (400.177~\si{\kilo\electronvolt}) are
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presented in Table~\ref{tab:xray_eff}. In the process of efficiency calibration,
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presented in Table~\ref{tab:xray_eff}. In the process of efficiency calibration,
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corrections for true coincidence summing and self-absorption were not applied.
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corrections for true coincidence summing and self-absorption were not applied.
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The true coincidence summing probability is estimated to be very
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The true coincidence summing probability is estimated to be very
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small, about \sn{5.4}{-6}, thanks to the far geometry of the calibration. The
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small, about \sn{5.4}{-6}, thanks to the far geometry of the calibration. The
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absorption in the source cover made of 22~\milli\gram\per\centi\meter$^2$
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absorption in the source cover made of 22~\si{\milli\gram\per\si{\centi\meter}^2}
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polyethylene is less than \sn{4}{-4} for a 100~\kilo\electronvolt\ photon.
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polyethylene is less than \sn{4}{-4} for a 100~\si{\kilo\electronvolt}\ photon.
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\begin{table}[htb]
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\begin{table}[htb]
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\begin{center}
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\begin{center}
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@@ -224,8 +225,8 @@ polyethylene is less than \sn{4}{-4} for a 100~\kilo\electronvolt\ photon.
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\caption{Energy spectrum of the $\rm^{152}\textrm{Eu}$ calibration source
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\caption{Energy spectrum of the $\rm^{152}\textrm{Eu}$ calibration source
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recorded by the germanium detector. The most prominent peaks of
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recorded by the germanium detector. The most prominent peaks of
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$^{152}\textrm{Eu}$ along with their energies are
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$^{152}\textrm{Eu}$ along with their energies are
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annotated in red; the 1460.82 \kilo\electronvolt~line is background from
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annotated in red; the 1460.82 \si{\kilo\electronvolt}~line is background from
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$^{40}\textrm{K}$; and the annihilation 511.0~\kilo\electronvolt~photons
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$^{40}\textrm{K}$; and the annihilation 511.0~\si{\kilo\electronvolt}~photons
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come both from the source and the surrounding environment.}
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come both from the source and the surrounding environment.}
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\label{fig:ge_eu152_spec}
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\label{fig:ge_eu152_spec}
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\end{figure}
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\end{figure}
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@@ -505,8 +506,8 @@ listed in Table~\ref{tab:mucap_pars}.
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The muonic X-ray spectrum emitted from the active target is shown in
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The muonic X-ray spectrum emitted from the active target is shown in
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Figure~\ref{fig:sir2_xray}. The $(2p-1s)$ line is seen at
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Figure~\ref{fig:sir2_xray}. The $(2p-1s)$ line is seen at
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399.5~\kilo\electronvolt, 0.7~\kilo\electronvolt\ off from the
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399.5~\si{\kilo\electronvolt}, 0.7~\si{\kilo\electronvolt}\ off from the
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reference value of 400.177~\kilo\electronvolt. This discrepancy is within our
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reference value of 400.177~\si{\kilo\electronvolt}. This discrepancy is within our
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detector's resolution, and the calculated efficiency is
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detector's resolution, and the calculated efficiency is
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$(4.549 \pm 0.108)\times 10^{-5}$ -- a 0.15\% increasing from that of the
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$(4.549 \pm 0.108)\times 10^{-5}$ -- a 0.15\% increasing from that of the
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400.177~keV line, so no attempt for recalibration or correction was made.
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400.177~keV line, so no attempt for recalibration or correction was made.
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@@ -529,7 +530,7 @@ corrected for several effects:
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\item Self-absorption effect: the X-rays emitted could be absorbed by the
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\item Self-absorption effect: the X-rays emitted could be absorbed by the
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target itself, the probability of self-absorption becomes larger in case of
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target itself, the probability of self-absorption becomes larger in case of
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thick sample and low energy photons.
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thick sample and low energy photons.
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For this silicon target of 1500~\micron\ thick and the photon energy of
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For this silicon target of 1500~\si{\micro\meter}\ thick and the photon energy of
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400~keV, and assuming a narrow muon stopping distribution at the centre of
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400~keV, and assuming a narrow muon stopping distribution at the centre of
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the target, the self-absorption correction is estimated to be:
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the target, the self-absorption correction is estimated to be:
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\begin{align}
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\begin{align}
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@@ -556,8 +557,8 @@ corrected for several effects:
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\centering
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\centering
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\includegraphics[width=0.85\textwidth]{figs/sir2_ges_self_tdiff}
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\includegraphics[width=0.85\textwidth]{figs/sir2_ges_self_tdiff}
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\caption{Interval between to consecutive pulses on the germanium
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\caption{Interval between to consecutive pulses on the germanium
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detector. The peak at 57~\micro\second\ indicates the pulse length, and
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detector. The peak at 57~\si{\micro\second}\ indicates the pulse length, and
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the bump at about 2000~\micro\second\ shows the width of the reset
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the bump at about 2000~\si{\micro\second}\ shows the width of the reset
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pulses. The average count rate of this detector is extracted from the
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pulses. The average count rate of this detector is extracted from the
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decay constant of the time spectrum to be
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decay constant of the time spectrum to be
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$5.146 \times 10^{-7}\textrm{ ns}^{-1} = 514.6 \textrm{ s}^{-1}$}
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$5.146 \times 10^{-7}\textrm{ ns}^{-1} = 514.6 \textrm{ s}^{-1}$}
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@@ -690,13 +691,13 @@ So, the emission rate is:
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%\end{figure}
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%\end{figure}
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%The spectrum measured by Sobottka and Wills~\cite{SobottkaWills.1968} is
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%The spectrum measured by Sobottka and Wills~\cite{SobottkaWills.1968} is
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%reproduced in Figure~\ref{fig:sobottka_spec}, the spectral integral in the
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%reproduced in Figure~\ref{fig:sobottka_spec}, the spectral integral in the
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%energy region from 8 to 10~\mega\electronvolt\ is $2086.8 \pm 45.7$.
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%energy region from 8 to 10~\si{\mega\electronvolt}\ is $2086.8 \pm 45.7$.
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%The authors obtained the spectrum in a 4~\micro\second\ gate period which began
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%The authors obtained the spectrum in a 4~\si{\micro\second}\ gate period which began
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%1~\micro\second\ after a muon stopped, which would take 26.59\% of the emitted
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%1~\si{\micro\second}\ after a muon stopped, which would take 26.59\% of the emitted
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%particles into account. The number of stopped muons was not explicitly stated,
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%particles into account. The number of stopped muons was not explicitly stated,
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%but can be inferred to be $55715/0.06 = 92858.3$.
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%but can be inferred to be $55715/0.06 = 92858.3$.
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%The partial rate of charged particle from 8 to 10~\mega\electronvolt\ is then
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%The partial rate of charged particle from 8 to 10~\si{\mega\electronvolt}\ is then
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%calculated to be:
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%calculated to be:
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%\begin{equation}
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%\begin{equation}
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%R_{\textrm{8-10 MeV}}^{lit.} =
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%R_{\textrm{8-10 MeV}}^{lit.} =
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@@ -704,7 +705,7 @@ So, the emission rate is:
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%= 1.28 \times 10^{-2}
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%= 1.28 \times 10^{-2}
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%\end{equation}
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%\end{equation}
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%The authors did not mentioned how the uncertainties of their measurement was
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%The authors did not mentioned how the uncertainties of their measurement was
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%derived, but quoted the emission rate below 26~\mega\electronvolt\ to be $0.15
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%derived, but quoted the emission rate below 26~\si{\mega\electronvolt}\ to be $0.15
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%\pm 0.02$, which translates to a relative uncertainty of 0.133. The statistical
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%\pm 0.02$, which translates to a relative uncertainty of 0.133. The statistical
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%uncertainty from the spectral integral and the number of stopped muons is:
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%uncertainty from the spectral integral and the number of stopped muons is:
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%\begin{equation*}
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%\begin{equation*}
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@@ -712,14 +713,14 @@ So, the emission rate is:
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%\end{equation*}
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%\end{equation*}
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%Then their systematic uncertainty would be: $0.133 - 0.009 = 0.124$.
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%Then their systematic uncertainty would be: $0.133 - 0.009 = 0.124$.
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%For the partial spectrum from 8 to 10~\mega\electronvolt, the statistical
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%For the partial spectrum from 8 to 10~\si{\mega\electronvolt}, the statistical
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%contribution to the uncertainty is:
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%contribution to the uncertainty is:
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%\begin{equation*}
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%\begin{equation*}
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%\dfrac{1}{\sqrt{2086.8}} + \dfrac{1}{\sqrt{92858.3}} = 2.5 \times 10^{-2}
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%\dfrac{1}{\sqrt{2086.8}} + \dfrac{1}{\sqrt{92858.3}} = 2.5 \times 10^{-2}
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%\end{equation*}
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%\end{equation*}
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%So, the combined uncertainty of this partial rate calculation is: $0.124
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%So, the combined uncertainty of this partial rate calculation is: $0.124
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%+ 0.025 = 0.150$. The partial rate of charged particles from 8 to
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%+ 0.025 = 0.150$. The partial rate of charged particles from 8 to
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%10~\mega\electronvolt per muon capture is:
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%10~\si{\mega\electronvolt} per muon capture is:
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%\begin{equation}
|
%\begin{equation}
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%R_{\textrm{8-10 MeV}}^{lit.} = (1.28 \pm 0.19) \times 10^{-2}
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%R_{\textrm{8-10 MeV}}^{lit.} = (1.28 \pm 0.19) \times 10^{-2}
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%\end{equation}
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%\end{equation}
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@@ -729,8 +730,8 @@ So, the emission rate is:
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\section{Charged particles following muon capture on a thin silicon target}
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\section{Charged particles following muon capture on a thin silicon target}
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\label{sec:charged_particles_following_muon_capture_on_a_thin_silicon_target}
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\label{sec:charged_particles_following_muon_capture_on_a_thin_silicon_target}
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In this measurement, a passive, 62-\micron-thick silicon target was used as the
|
In this measurement, a passive, 62-\si{\micro\meter}-thick silicon target was used as the
|
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target. The silicon target is $5\times5$~\centi\meter$^2$ in area. The muon
|
target. The silicon target is $5\times5$~\si{\centi\meter}$^2$ in area. The muon
|
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momentum was chosen to be 1.06 after a scanning to maximise the stopping ratio.
|
momentum was chosen to be 1.06 after a scanning to maximise the stopping ratio.
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The charged particles were measured by two arms of silicon detectors. The
|
The charged particles were measured by two arms of silicon detectors. The
|
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plastic scintillators vetoing information were not used.
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plastic scintillators vetoing information were not used.
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@@ -754,17 +755,17 @@ tree contains total $1.452 \times 10^8$ muon events. %145212698
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\subsection{Particle identification by dE/dx and proton selection}
|
\subsection{Particle identification by dE/dx and proton selection}
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\label{sub:particle_identification_by_de_dx}
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\label{sub:particle_identification_by_de_dx}
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%All silicon hits with energy deposition larger than
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%All silicon hits with energy deposition larger than
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%200~\kilo\electronvolt\ that happened within $\pm 10$~\micro\second\ of the
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%200~\si{\kilo\electronvolt}\ that happened within $\pm 10$~\si{\micro\second}\ of the
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%muon hit are then
|
%muon hit are then
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%associated to the muon and stored in the muon event tree. The
|
%associated to the muon and stored in the muon event tree. The
|
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%200~\kilo\electronvolt\ cut effectively rejects all MIPs hits on thin silicon
|
%200~\si{\kilo\electronvolt}\ cut effectively rejects all MIPs hits on thin silicon
|
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%detectors of which the most probable value is about 40~\kilo\electronvolt.
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%detectors of which the most probable value is about 40~\si{\kilo\electronvolt}.
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|
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%In order to use dE/dx for particle identification, $\Delta$E and total E are
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%In order to use dE/dx for particle identification, $\Delta$E and total E are
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%needed.
|
%needed.
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The charged particle selection starts from searching for muon event
|
The charged particle selection starts from searching for muon event
|
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that has at least one hit on thick silicon. If there is a thin silicon hit
|
that has at least one hit on thick silicon. If there is a thin silicon hit
|
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within a coincidence window of $\pm 0.5$~\micro\second\ around the thick
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within a coincidence window of $\pm 0.5$~\si{\micro\second}\ around the thick
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silicon hit, the two hits are considered to belong to one particle with
|
silicon hit, the two hits are considered to belong to one particle with
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$\Delta$E being the energy of the thin hit, and total E being the sum energy of
|
$\Delta$E being the energy of the thin hit, and total E being the sum energy of
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the two hits. Particle identification is done using correlation between
|
the two hits. Particle identification is done using correlation between
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@@ -786,8 +787,8 @@ $\Delta$E-E plots can be identified as follows:
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\end{itemize}
|
\end{itemize}
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|
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%The electrons either from Michel decay or from the beam are MIPs particles,
|
%The electrons either from Michel decay or from the beam are MIPs particles,
|
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%which would deposit about 466~keV on the 1500-\micron-thick silicon detector,
|
%which would deposit about 466~keV on the 1500-\si{\micro\meter}-thick silicon detector,
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%and about 20~keV on the 65-\micron-thick silicon detector. Therefore our thin
|
%and about 20~keV on the 65-\si{\micro\meter}-thick silicon detector. Therefore our thin
|
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%silicon counters could not distinguish electrons from electronic
|
%silicon counters could not distinguish electrons from electronic
|
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%noise. The brightest spots on the $\Delta$E-E plots are identified as electrons
|
%noise. The brightest spots on the $\Delta$E-E plots are identified as electrons
|
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%due to
|
%due to
|
||||||
@@ -864,7 +865,7 @@ The double peaks of muonic X-rays from the lead shield at 431 and 438~keV are
|
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very intense, reflects the fact that the low momentum muon beam of
|
very intense, reflects the fact that the low momentum muon beam of
|
||||||
29.68~MeV\cc\ (scaling factor 1.06) was strongly scattered by the upstream
|
29.68~MeV\cc\ (scaling factor 1.06) was strongly scattered by the upstream
|
||||||
counters. After a prompt cut that requires the photon
|
counters. After a prompt cut that requires the photon
|
||||||
hit occured in $\pm 1$~\micro\second\ around the muon hit, the peaks from lead
|
hit occured in $\pm 1$~\si{\micro\second}\ around the muon hit, the peaks from lead
|
||||||
remain prominent which is an expected result because of all the lead shield
|
remain prominent which is an expected result because of all the lead shield
|
||||||
inside the chamber was to capture stray muons. The cut shows its effect on
|
inside the chamber was to capture stray muons. The cut shows its effect on
|
||||||
reducing the background level under the 400.177 keV peak by about one third.
|
reducing the background level under the 400.177 keV peak by about one third.
|
||||||
@@ -872,7 +873,7 @@ reducing the background level under the 400.177 keV peak by about one third.
|
|||||||
\begin{figure}[htb]
|
\begin{figure}[htb]
|
||||||
\centering
|
\centering
|
||||||
\includegraphics[width=0.98\textwidth]{figs/si16p_xray}
|
\includegraphics[width=0.98\textwidth]{figs/si16p_xray}
|
||||||
\caption{X-ray spectrum from the passive 62-\micron-thick silicon target with
|
\caption{X-ray spectrum from the passive 62-\si{\micro\meter}-thick silicon target with
|
||||||
and with out timing cut.}
|
and with out timing cut.}
|
||||||
\label{fig:si16_xray}
|
\label{fig:si16_xray}
|
||||||
\end{figure}
|
\end{figure}
|
||||||
@@ -918,10 +919,10 @@ Table~\ref{tab:si16p_ncapture_cal}.
|
|||||||
\label{sub:lifetime_measurement}
|
\label{sub:lifetime_measurement}
|
||||||
To check the origin of the protons recorded, lifetime measurements were made by
|
To check the origin of the protons recorded, lifetime measurements were made by
|
||||||
cutting on time difference between a hit on one thick silicon and the muon
|
cutting on time difference between a hit on one thick silicon and the muon
|
||||||
hit. Applying the time cut in 0.5~\micro\second\ time steps on the proton
|
hit. Applying the time cut in 0.5~\si{\micro\second}\ time steps on the proton
|
||||||
events in Figure~\ref{fig:si16p_proton_after_ecut}, the number of surviving
|
events in Figure~\ref{fig:si16p_proton_after_ecut}, the number of surviving
|
||||||
protons on each arm are plotted on Figure~\ref{fig:si16p_proton_lifetime}. The
|
protons on each arm are plotted on Figure~\ref{fig:si16p_proton_lifetime}. The
|
||||||
curves show decay constants of $762.9 \pm 13.7$~\nano\second\ and $754.6 \pm
|
curves show decay constants of $762.9 \pm 13.7$~\si{\nano\second}\ and $754.6 \pm
|
||||||
11.9$,
|
11.9$,
|
||||||
which are consistent with the each other, and with mean life time of muons in
|
which are consistent with the each other, and with mean life time of muons in
|
||||||
silicon in the literatures of $758 \pm 2$~\cite{}. This is the confirmation
|
silicon in the literatures of $758 \pm 2$~\cite{}. This is the confirmation
|
||||||
@@ -941,7 +942,7 @@ Therefore a timing cut from 500~ns is used to select good silicon events, the
|
|||||||
remaining protons are shown in Figure~\ref{fig:si16p_proton_ecut_500nstcut}.
|
remaining protons are shown in Figure~\ref{fig:si16p_proton_ecut_500nstcut}.
|
||||||
The spectra have a low energy cut off at 2.5~MeV because protons with energy
|
The spectra have a low energy cut off at 2.5~MeV because protons with energy
|
||||||
lower than that could not pass through the thin silicon to make the cuts as the
|
lower than that could not pass through the thin silicon to make the cuts as the
|
||||||
range of 2.5~MeV protons in silicon is about 68~\micron.
|
range of 2.5~MeV protons in silicon is about 68~\si{\micro\meter}.
|
||||||
\begin{figure}[htb]
|
\begin{figure}[htb]
|
||||||
\centering
|
\centering
|
||||||
\includegraphics[width=0.85\textwidth]{figs/si16p_proton_ecut_500nstcut}
|
\includegraphics[width=0.85\textwidth]{figs/si16p_proton_ecut_500nstcut}
|
||||||
@@ -1058,7 +1059,7 @@ The ratio between the number of protons and other particles at 500~ns is $(1927
|
|||||||
%\centering
|
%\centering
|
||||||
%\includegraphics[width=0.85\textwidth]{figs/si16p_toyMC}
|
%\includegraphics[width=0.85\textwidth]{figs/si16p_toyMC}
|
||||||
%\caption{An example of response function between the observed energy and
|
%\caption{An example of response function between the observed energy and
|
||||||
%initial energy of protons in a 62-\micron-target.}
|
%initial energy of protons in a 62-\si{\micro\meter}-target.}
|
||||||
%\label{fig:si16p_toyMC}
|
%\label{fig:si16p_toyMC}
|
||||||
%\end{figure}
|
%\end{figure}
|
||||||
|
|
||||||
@@ -1096,7 +1097,7 @@ The ratio between the number of protons and other particles at 500~ns is $(1927
|
|||||||
%\subsection{Proton emission rate and uncertainties estimation}
|
%\subsection{Proton emission rate and uncertainties estimation}
|
||||||
%\label{sub:proton_emission_rate_and_uncertainties_estimation}
|
%\label{sub:proton_emission_rate_and_uncertainties_estimation}
|
||||||
|
|
||||||
%The rate of proton emission from 2.5--10~\mega\electronvolt is:
|
%The rate of proton emission from 2.5--10~\si{\mega\electronvolt} is:
|
||||||
%\begin{equation}
|
%\begin{equation}
|
||||||
%R =
|
%R =
|
||||||
%\end{equation}
|
%\end{equation}
|
||||||
@@ -1119,7 +1120,7 @@ The ratio between the number of protons and other particles at 500~ns is $(1927
|
|||||||
\section{Proton emission following muon capture on an aluminium target}
|
\section{Proton emission following muon capture on an aluminium target}
|
||||||
\label{sec:proton_emission_following_muon_capture_on_an_aluminium_target}
|
\label{sec:proton_emission_following_muon_capture_on_an_aluminium_target}
|
||||||
The aluminium is the main object of the AlCap experiment, in this preliminary
|
The aluminium is the main object of the AlCap experiment, in this preliminary
|
||||||
analysis I chose one target, Al100 the 100-\micron-thick target, on
|
analysis I chose one target, Al100 the 100-\si{\micro\meter}-thick target, on
|
||||||
a sub-range of the data set runs 2808--2873, as a demonstration.
|
a sub-range of the data set runs 2808--2873, as a demonstration.
|
||||||
Because this is a passive target, the same procedure and cuts used in the
|
Because this is a passive target, the same procedure and cuts used in the
|
||||||
passive silicon runs were applied.
|
passive silicon runs were applied.
|
||||||
@@ -1163,8 +1164,8 @@ proton energy spectrum is shown in Figure~\ref{fig:al100_proton_spec}.
|
|||||||
|
|
||||||
The lifetime of these protons are shown in
|
The lifetime of these protons are shown in
|
||||||
Figure~\ref{fig:al100_proton_lifetime}, the fitted decay constant on the right
|
Figure~\ref{fig:al100_proton_lifetime}, the fitted decay constant on the right
|
||||||
arm is consistent with the reference value of $864 \pm 2$~\nano\second~\cite{}.
|
arm is consistent with the reference value of $864 \pm 2$~\si{\nano\second}~\cite{}.
|
||||||
But the left arm gives $918 \pm 16.1$~\nano\second, significantly larger than
|
But the left arm gives $918 \pm 16.1$~\si{\nano\second}, significantly larger than
|
||||||
the reference value.
|
the reference value.
|
||||||
%The longer lifetime suggested some contributions from
|
%The longer lifetime suggested some contributions from
|
||||||
%other lighter materials, one possible source is from muons captured on the back
|
%other lighter materials, one possible source is from muons captured on the back
|
||||||
@@ -1180,7 +1181,7 @@ the reference value.
|
|||||||
Further investigation of the problem of longer lifetime was made and the first
|
Further investigation of the problem of longer lifetime was made and the first
|
||||||
channel on the thin silicon detector on that channel was the offender. The
|
channel on the thin silicon detector on that channel was the offender. The
|
||||||
lifetime measurement with out that SiL1-1 channel gives a reasonable result,
|
lifetime measurement with out that SiL1-1 channel gives a reasonable result,
|
||||||
and the decay constant on the SiL1-1 alone was nearly about 1000~\micro\second.
|
and the decay constant on the SiL1-1 alone was nearly about 1000~\si{\micro\second}.
|
||||||
The reason for this behaviour is not known yet. For this emission rate
|
The reason for this behaviour is not known yet. For this emission rate
|
||||||
calculation, this channel is discarded and the rate on the left arm is scaled
|
calculation, this channel is discarded and the rate on the left arm is scaled
|
||||||
with a factor of 4/3. The proton spectrum from the aluminium target is plotted
|
with a factor of 4/3. The proton spectrum from the aluminium target is plotted
|
||||||
|
|||||||
@@ -51,7 +51,31 @@ bookmarks
|
|||||||
\RequirePackage{setspace}
|
\RequirePackage{setspace}
|
||||||
\RequirePackage{verbatim}
|
\RequirePackage{verbatim}
|
||||||
\RequirePackage{lipsum}
|
\RequirePackage{lipsum}
|
||||||
|
\RequirePackage{datatool}
|
||||||
|
\RequirePackage[capitalise]{cleveref}
|
||||||
|
\RequirePackage[final]{listings}
|
||||||
|
\RequirePackage{xfrac}
|
||||||
|
%% Units
|
||||||
\RequirePackage[]{siunitx}
|
\RequirePackage[]{siunitx}
|
||||||
|
%% Various fonts ...
|
||||||
|
%\RequirePackage[T1]{fontenc}
|
||||||
|
%\RequirePackage{charter}
|
||||||
|
%\RequirePackage[expert]{mathdesign}
|
||||||
|
|
||||||
|
|
||||||
|
%\usepackage[T1]{fontenc}
|
||||||
|
%\usepackage[bitstream-charter]{mathdesign}
|
||||||
|
|
||||||
|
|
||||||
|
%\RequirePackage{lmodern}
|
||||||
|
%\RequirePackage{libertine}
|
||||||
|
%\RequirePackage[libertine]{newtxmath}
|
||||||
|
|
||||||
|
% this works
|
||||||
|
%\usepackage[]{mathpazo} % With old-style figures and real smallcaps.
|
||||||
|
%\linespread{1.025} % Palatino leads a little more leading
|
||||||
|
%\usepackage[small]{eulervm}
|
||||||
|
|
||||||
\RequirePackage{tabularx}
|
\RequirePackage{tabularx}
|
||||||
\RequirePackage{color}
|
\RequirePackage{color}
|
||||||
\RequirePackage{pifont}
|
\RequirePackage{pifont}
|
||||||
|
|||||||
@@ -24,17 +24,17 @@ for the COMET experiment}
|
|||||||
\date{September, 2014}
|
\date{September, 2014}
|
||||||
|
|
||||||
\begin{document}
|
\begin{document}
|
||||||
\begin{frontmatter}
|
%\begin{frontmatter}
|
||||||
\input{chapters/frontmatter}
|
%\input{chapters/frontmatter}
|
||||||
\end{frontmatter}
|
%\end{frontmatter}
|
||||||
|
|
||||||
\mainmatter
|
\mainmatter
|
||||||
\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}
|
||||||
|
|
||||||
\begin{backmatter}
|
\begin{backmatter}
|
||||||
|
|||||||
Reference in New Issue
Block a user