diff --git a/thesis/chapters/chap6_analysis.tex b/thesis/chapters/chap6_analysis.tex index 3d60cdf..3fa28dd 100644 --- a/thesis/chapters/chap6_analysis.tex +++ b/thesis/chapters/chap6_analysis.tex @@ -465,6 +465,22 @@ The proton emission rate in the range from \SIrange{5}{8}{\MeV} is therefore: \label{eq:proton_rate_al} \end{equation} -\subsection{Uncertainties of the emission rate} -\label{sub:uncertainties_of_the_emission_rate} +%\subsection{Uncertainties of the emission rate} +%\label{sub:uncertainties_of_the_emission_rate} +%The uncertainties of the emission rate come from: +%\begin{itemize} + %\item uncertainties in the number of protons: + %\begin{itemize} + %\item statistical uncertainty of the measured spectra; + %\item systematic uncertainty due to misidentification; + %\item systematic uncertainty from the unfolding + %\end{itemize} + %\item uncertainties in the number of nuclear captures: + %\begin{itemize} + %\item statistical uncertainty of the number of X-rays; + %\item uncertainty of the detector acceptance; + %\item uncertainty from the corrections: random summing and transistor + %reset amplifier + %\end{itemize} +%\end{itemize} diff --git a/thesis/chapters/chap7_results.tex b/thesis/chapters/chap7_results.tex index 0019bec..0e8d39e 100644 --- a/thesis/chapters/chap7_results.tex +++ b/thesis/chapters/chap7_results.tex @@ -1,74 +1,14 @@ -\chapter{Discussions} -\label{cha:discussions} +\chapter{Results and discussions} +\label{cha:results_and_discussions} +\section{Verification of the experimental method} +\label{sec:verification_of_the_experimental_method} -\section{Thick aluminium target measurement} -\label{sub:active_target_measurement} -With a thick and active silicon target, I have tried to reproduce an existing -result from Sobottka and Wills~\cite{SobottkaWills.1968}. This is important in -giving confidence in our experimental method. The idea is the same as that of -the old measurement, where muons were stopped inside a bulk active target and -the capture products were measured. Due to the limitation of the -currently available analysis tool, a direct comparison with the result of -Sobottka and Wills is not practical at the moment. +\subsection{Number of stopped muons normalisation} +\label{sub:number_of_stopped_muons_normalisation} -But a partial comparison is available for a part of the spectrum from 8 to -10~MeV, where my result of $(1.22 \pm 0.19) \times 10^{-2} $ is consistent with -the derived value $(1.28\pm0.19)\times10^{-2}$ from the paper of Sobottka and -Wills. The agreement was partly because of large error bars in both results. -In my part, the largest error came from the uncertainty on choosing the -integration window. This can be solved with a more sophisticated pulse -finding/calculating algorithm so that the contribution of muons in the energy -spectrum can be eliminated by imposing a cut in pulse timing. The -under-testing pulse template fitting module could do this job soon. - -The range of 8--10~MeV was chosen to be large enough so that the uncertainty of -integration window would not to be too great; and at the same time be small -enough so the protons (and other heavier charged particles) would not escape -the active target. This range is also more convenient for calculating the -partial rate from the old paper of Sobottka and Wills. - -% section protons_following_muon_capture_on_silicon (end) -%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% - -\section{Thin silicon target measurement} -\label{sub:thin_and_passive_target_measurement} -The charged particles in the low energy region of 2.5--8~MeV were measured by -dE/dx method. The particle identification was good in lower energy part, but -losing its resolution power as energy increases. The current set up could do -the PID up to about 8~MeV for protons. This energy range is exactly the -relevant range to the COMET experiment (Figure~\ref{fig:proton_impact_CDC}). - -In that useful energy range, the analysis showed a good separation of protons -from other heavy charged particles. The contribution of protons in the total -charged particles is 87\%. This is the high limit only since the heavier -particles at this energy range are most likely to stopped in the thin -detectors. More statistic would be needed to estimate the contributions from -other particles. - -The effective emission rate of protons per muon capture in this measurement is -4.20\%, with a large uncertainty contribution comes from limitation of the -timing determination. The spectral integral in the region 2.5--8~MeV on -Figure~\ref{fig:sobottka_spec} is about 70\% of the spectrum from 1.4 to -26~\MeV, and corresponds to an emission rate of about 10\% per muon capture. -The two figures are not in disagreement. - -In order to have a better comparison, a correction or unfolding for energy -loss and more MC simulation study are needed. I am on progress of these study. - -% subsection thin_and_passive_target_measurement (end) -%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% -\section{Aluminium target measurement} -\label{sec:aluminium_target_measurement} -The proton emission rate was derived as 2.37\%, but the problem on the SiL1-1 -channel was not solved yet. One possible cause is the muons captured on other -lighter material inside the chamber. More investigation will be made on this -matter. - -The rate of 2.37\% on aluminium appears to be smaller on that of silicon but -the two results are both effective rates, modified by energy loss inside the -target. Unfolding and MC study for the correction are ongoing. -% section aluminium_target_measurement (end) -%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% -% chapter discussions (end) +\subsection{Particle identification and unfolding} +\label{sub:particle_identification_and_unfolding} +\section{Emission rate of protons and the COMET Phase I's CDC} +\label{sec:emission_rate_of_protons_and_the_comet_phase_i_s_cdc} diff --git a/thesis/thesis.bib b/thesis/thesis.bib index 91adc65..154be37 100644 --- a/thesis/thesis.bib +++ b/thesis/thesis.bib @@ -119,8 +119,6 @@ Year = {2003}, Pages = {250-303}, Volume = {A506}, - - __markedentry = {[NT:6]}, Collaboration = {GEANT4}, Doi = {10.1016/S0168-9002(03)01368-8}, Owner = {NT}, @@ -487,8 +485,6 @@ Number = {1}, Pages = {154--197}, Volume = {562}, - - __markedentry = {[NT:]}, Doi = {10.1016/j.nima.2006.03.009}, File = {Published version:Bichsel.2006.pdf:PDF}, Owner = {NT}, @@ -1284,6 +1280,25 @@ Timestamp = {2014-04-01} } +@Article{IsaakEngfer.etal.1983, + Title = {{INCLUSIVE NEUTRON AND CHARGED PARTICLE SPECTRA FROM THE + ABSORPTION OF STOPPED NEGATIVE PIONS IN NICKEL ISOTOPES}}, + Author = {Isaak, H.P. and Engfer, R. and Hartmann, R. and Hermes, + E.A. and Pruys, H.S. and others}, + Journal = {Nucl.Phys.}, + Year = {1983}, + Pages = {385}, + Volume = {A392}, + + __markedentry = {[NT:]}, + Doi = {10.1016/0375-9474(83)90134-3}, + File = {Published version:IsaakEngfer.etal.1983.pdf:PDF}, + Owner = {NT}, + Reportnumber = {SIN-PR-81-12}, + Slaccitation = {%%CITATION = NUPHA,A392,385;%%}, + Timestamp = {2014-10-16} +} + @Article{Ishii.1959, Title = {An Analysis of the Charged Particles Emitted Following Negative Muon Absorptions in Photographic Emulsions}, Author = {Ishii, Chikai}, @@ -1511,6 +1526,54 @@ Url = {http://prola.aps.org/abstract/PR/v165/i4/p1190_1} } +@Article{KozlowskiZglinski.1978, + Title = {{The Nuclear Excitations and Particle Emission Following + Muon Capture}}, + Author = {Kozlowski, T. and Zglinski, A.}, + Journal = {Nucl.Phys.}, + Year = {1978}, + Pages = {368-380}, + Volume = {A305}, + + __markedentry = {[NT:]}, + Doi = {10.1016/0375-9474(78)90345-7}, + File = {Published version:KozlowskiZglinski.1978.pdf:PDF}, + Owner = {NT}, + Slaccitation = {%%CITATION = NUPHA,A305,368;%%}, + Timestamp = {2014-10-16} +} + +@Article{KozlowskiZglinski.1974, + Title = {{Nuclear muon capture - a simple model}}, + Author = {Kozlowski, T. and Zglinski, A.}, + Journal = {Phys.Lett.}, + Year = {1974}, + Pages = {222-224}, + Volume = {B50}, + + __markedentry = {[NT:]}, + Doi = {10.1016/0370-2693(74)90543-7}, + File = {Published version:KozlowskiZglinski.1974.pdf:PDF}, + Owner = {NT}, + Slaccitation = {%%CITATION = PHLTA,B50,222;%%}, + Timestamp = {2014-10-16} +} + +@Article{KozlowskiZglinski.1974b, + Title = {{Pre-equilibrium particle emission after the nuclear muon + capture}}, + Author = {Kozlowski, T. and Zglinski, A.}, + Journal = {Nukleonika}, + Year = {1974}, + Pages = {721-725}, + Volume = {19}, + + __markedentry = {[NT:6]}, + Owner = {NT}, + Slaccitation = {%%CITATION = NUKLA,19,721;%%}, + Timestamp = {2014-10-16} +} + @Article{KraneSharma.etal.1979, Title = {Energetic charged-particle spectrum following $\mu$-capture by nuclei}, Author = {Krane, KS and Sharma, TC and Swenson, LW and McDaniels, DK and Varghese, P and Wood, BE and Silbar, RR and Wohlfahrt, HD and Goulding, CA}, @@ -2503,6 +2566,7 @@ Year = {2003}, Pages = {MOLT007}, Volume = {C0303241}, + Archiveprefix = {arXiv}, Eprint = {physics/0306116}, File = {arXiv v1:VerkerkeKirkby.2003-eprintv1.pdf:PDF}, diff --git a/thesis/thesis.tex b/thesis/thesis.tex index ac73cc3..d9df6d7 100644 --- a/thesis/thesis.tex +++ b/thesis/thesis.tex @@ -29,13 +29,13 @@ for the COMET experiment} \end{frontmatter} \mainmatter -%\input{chapters/chap1_intro} -%\input{chapters/chap2_mu_e_conv} -%\input{chapters/chap3_comet} +\input{chapters/chap1_intro} +\input{chapters/chap2_mu_e_conv} +\input{chapters/chap3_comet} \input{chapters/chap4_alcap_phys} \input{chapters/chap5_alcap_setup} \input{chapters/chap6_analysis} -%\input{chapters/chap7_results} +\input{chapters/chap7_results} \begin{backmatter} \input{chapters/backmatter}