%% Title
%\titlepage[\vspace{5mm}Department of Physics,\\
%Graduate School of Science]%
%{A dissertation submitted to the Osaka University\\
%for the degree of Doctor of Philosophy}
\titlepage[]{\vspace{5mm}Department of Physics, Graduate School of Science\\
Osaka University}

%% Abstract
\begin{abstract}
  %[\smaller \thetitle\\ \vspace*{1cm} \smaller {\theauthor}]
  \thispagestyle{empty}
  COMET [1] is an experiment that aims to search for a charged lepton flavour
violation (CLFV) process, the muon-to-electron conversion in the presence of
a nucleus,
\muec. The process is forbidden in the Standard Model (SM), however is
predicted to occur in various extensions of SM, such as . Current experimental
upper limit of the branching ratio is $BR(\mu^{-} + Au \rightarrow e^{-} + Au)
< 7 \times 10^{-13}$, set by the SINDRUM II experiment [2].

Using the J-PARC proton beam and the pion capture by
a solenoidal field, COMET will have a single event sensitivity  10,000 times
better than the current limit. The COMET collaboration has taken a phased
approach in which the first phase, COMET Phase-I [3], starts in 2013 and
initial data taking in around 2017. 

In order to optimize detector design for the Phase-I, backgrounds from nuclear
muon capture are crucial. We have proposed a dedicated experiment, namely
AlCap, at PSI, Switzerland to study the backgrounds, including protons,
neutrons and photons. The measurements of proton rate and spectrum on
aluminium have been carried out in the 2013 run. The second run to study
neutrons and photons is planned in 2015.

The preliminary results from the analysis of the 2013 run are presented in this
thesis. The measured proton spectrum peaks at \SI{4}{\MeV} and decays
exponentially with the decay constant of \SI{2.6}{\MeV}. The emission
rate of protons in the energy range from \SIrange{4}{8}{\MeV} is
$(1.7\pm0.1)\%$. The total proton emission rate is estimated to be
$(3.5\pm0.2)\%$ assuming the spectrum shape holds.
The resulted proton rate and spectrum were used to optimise the tracking
detector hit rate of the COMET Phase-I.

\end{abstract}


%% Declaration
\begin{declaration}
  \thispagestyle{empty}
  This dissertation is the result of my own work, except where explicit
  reference is made to the work of others, and has not been submitted
  for another qualification to this or any other university. 
  \vspace*{1cm}
  \begin{flushright}
    Nam Hoai Tran
  \end{flushright}
\end{declaration}


% Acknowledgements
%\begin{acknowledgements}
  %\thispagestyle{empty}
  %Of the many people who deserve thanks, some are particularly prominent,
  %such as my supervisor Professor Yoshitaka Kuno.
%\end{acknowledgements}


%% Preface
%\begin{preface}
  %\thispagestyle{empty}
  %The thesis is about measurements of products of nuclear muon capture on an
  %aluminium target, which is important for optimization of a tracking detector
  %of a search for muon to electron conversion, the E21 experiment - so called
  %COMET - at Japan Proton Accelerator Complex (J-PARC).
%\end{preface}

%% ToC
\tableofcontents


%% Strictly optional!
%\frontquote{%
	%Writing in English is the most ingenious torture\\
%ever devised for sins committed in previous lives.}%
%{James Joyce}
