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diff --git a/macros/latex/contrib/hepthesis/example/chap2.tex b/macros/latex/contrib/hepthesis/example/chap2.tex new file mode 100644 index 0000000000..c365719223 --- /dev/null +++ b/macros/latex/contrib/hepthesis/example/chap2.tex @@ -0,0 +1,92 @@ +\chapter{The \LHCb experiment} +\label{chap:MoreStuff} + +\chapterquote{There, sir! that is the perfection of vessels!} +{Jules Verne, 1828--1905} + +\section{The \LHC} +The Large Hadron Collider (\LHC) at \CERN is a new hadron collider, +located in the same tunnel as the Large Electron-Positron collider +(\LEP)~\cite{Brianti:2004qq}. Where \LEP's chief task was the use +of \unit{90--207}{\GeV} \epluseminus collisions to establish the +precision physics of electroweak unification\dots + +% \begin{figure} +% \includegraphics[width=\largefigwidth]{ckmfitter-alpha-combined} +% \caption[CKM Fitter constraints on \alphaCKM.]% +% {CKM Fitter constraints on \alphaCKM from combined \BToPiPi, +% \BToRhoPi and \BToRhoRho decay analyses.} +% \label{fig:CKMFitter} +% \end{figure} + +\section{The \LHCb experiment} +\label{sec:LHCbInDetail} + +Since both \bhadron{s} are preferentially produced in the same direction +and are forward-boosted along the beam-pipe, the detector is not required +to have full $4\pi$ solid-angle coverage. \LHCb takes advantage of this +by using a wedge-shaped single-arm detector with angular acceptance +\unit{10-300}{\mrad} in the horizontal (bending) plane~\cite{Amato:1998xt}. + +\vspace{1cm} + +\begin{center} +{\hspace{1mm}\Large\vdots\hspace{1cm}} +\end{center} + +\vspace{1cm} + +The detector is illustrated in \FigureRef{fig:LHCbCrossSection}, showing +the overall scale of the experiment and the surrounding cavern structure. + +\begin{sidewaysfigure} + \begin{center} + \includegraphics[width=0.8\textheight]{lhcb-detector-cross-section} + \caption[Cross-section view of \LHCb, cut in the non-bending $y$--$z$ plane]% + {Cross-section view of \LHCb, cut in the non-bending $y$--$z$ plane.} + \label{fig:LHCbCrossSection} + \end{center} +\end{sidewaysfigure} + +The single-sided detector design was chosen in preference to a two-armed +design since the detector dimensions are restricted by the layout of the +IP8 (ex-Delphi) cavern in which \LHCb is located. Using all the available +space for a single-arm spectrometer more than compensates in performance +for the \about{50\percent} drop in luminosity. + +\section{The \Cerenkov mechanism} +A Huygens construction in terms of spherical shells of probability for photon +emission as the particle progresses along its track shows an effective +``shock-front'' of \Cerenkov emission. This corresponds to an emission cone of +opening angle \thetaCerenkov around the momentum vector for each point on the +track, +% +\begin{subequations} + \label{eq:cosThetaCk} + \begin{equation} + \cos\,\thetaCerenkov &= \frac{1}{n \beta} + + \frac{\hbar k}{2p}% + \parenths{ 1 - \frac{1}{n^2} } \\ + &\,\sim \frac{1}{n \beta}% + \label{eq:cosThetaCkApprox} + \end{equation} +\end{subequations} +% +where $\beta \equiv v/c$, the relativistic velocity fraction. + +\section{Trigger system} +\label{sec:triggers} +An overview of the \LHCb trigger characteristics broken down by level +is shown in \Table~\ref{tab:TriggerDetails}. + +\begin{table}[bp] + \begin{tabular}{lllll} + & L0 & L1 & HLT \\ + \midrule\\ + Input rate & \unit{40}{\MHz} & \unit{1}{\MHz} & \unit{40}{\kHz} \\ + Output rate & \unit{1}{\MHz} & \unit{40}{\kHz} & \unit{2}{\kHz} \\ + Location & On detector & Counting room & Counting room \\ + \end{tabular} + \caption{Characteristics of the trigger levels and offline analysis.} + \label{tab:TriggerDetails} +\end{table} |