% rubber: module pdftex \documentclass[english,aspectratio=43,8pt]{beamer} \usepackage{graphicx} \usepackage{amssymb} \usepackage{booktabs} \usepackage{siunitx} \usepackage{subcaption} \usepackage{marvosym} \usepackage{verbatim} \usepackage[normalem]{ulem} % Needed for /sout \newcommand{\pb}{\si{\pico\barn}}% \newcommand{\fb}{\si{\femto\barn}}% \newcommand{\invfb}{\si{\per\femto\barn}} \newcommand{\GeV}{\si{\giga\electronvolt}} \hypersetup{colorlinks=true,urlcolor=blue} \usetheme[]{bjeldbak} \begin{document} \title[e Reco. Validation]{Offline Electron Seeding Validation \-- Update} \author[C. Fangmeier]{\textbf{Caleb Fangmeier} \\ Ilya Kravchenko, Greg Snow} \institute[UNL]{University of Nebraska \-- Lincoln} \date{EGamma Workshop | November 21, 2017} \titlegraphic{% \begin{figure} \includegraphics[width=1in]{CMSlogo.png}\hspace{0.75in}\includegraphics[width=1in]{nebraska-n.png} \end{figure} } \begin{frame}[plain] \titlepage% \end{frame} \begin{frame}{Introduction} \begin{itemize} \item Our goal is to study \textbf{seeding} for the \textbf{offline} GSF tracking with the \textbf{new pixel detector}. \item Specifically, we want to optimize the window sizes used in the new pixel-matching scheme already implemented in HLT. \item Since last update\footnote{https://indico.cern.ch/event/662743/contributions/2744847/attachments/1534642/2403597/main.pdf}, \begin{itemize} \item Migrated Code from \texttt{9\_0\_2} to \texttt{9\_2\_8} \item Integrated the new pixel matching into the trackingNtuple. (although still a work-in-progress) \item Regenerated \texttt{trackingNtuple}s for dataset \\ {\tiny \vspace{0.05in}\hspace{-0.2in}\texttt{/ZToEE\_NNPDF30\_13TeV-powheg\_M\_120\_200/ \vspace{-0.05in}\hspace{-0.2in}RunIISummer17DRStdmix-NZSFlatPU28to62\_92X\_upgrade2017\_realistic\_v10-v1/GEN-SIM-RAW}}\vspace{0.05in} \item Ongoing work happening here: \url{https://github.com/cfangmeier/cmssw/tree/ValidationGsfTracks928_dev} \end{itemize} \item This Talk: \begin{itemize} \item Description of current Offline electron seeding \item Description of current HLT (future Offline) electron seeding \item Plans for 2018 \end{itemize} \end{itemize} \end{frame} \begin{frame}{Pair Electron Seeding I} \begin{columns} \begin{column}{0.75\textwidth} \begin{figure} \includegraphics[width=\textwidth]{diagrams/Gsf_Seeding1.png} \end{figure} \end{column} \begin{column}{0.25\textwidth} \begin{figure} \hspace{-1in} \vspace{-1in} \includegraphics[width=1.8\textwidth]{diagrams/window1.png} \end{figure} \end{column} \end{columns} \vfill \footnotesize{Windows from \url{https://indico.cern.ch/event/611042/contributions/2464057/attachments/1406271/2148742/ElectronTracking30112016.pdf}} \end{frame} \begin{frame}{Pair Electron Seeding II} \begin{columns} \begin{column}{0.66\textwidth} \begin{figure} \includegraphics[width=\textwidth]{diagrams/Gsf_Seeding2.png} \end{figure} \end{column} \begin{column}{0.33\textwidth} \begin{figure} \hspace{-0.75in} \vspace{1in} \includegraphics[width=1.5\textwidth]{diagrams/window2.png} \end{figure} \end{column} \end{columns} \end{frame} \begin{frame}{Pair Electron Seeding III} \begin{center} \begin{figure} \includegraphics[width=\textwidth]{diagrams/Gsf_Seeding3.png} \end{figure} \end{center} \end{frame} \begin{frame}{Triplet Electron Seeding - Setup} \begin{columns} \begin{column}{0.45\textwidth} \begin{itemize} \item Begin with ECAL super cluster and beam spot \end{itemize} \end{column} \begin{column}{0.55\textwidth} \begin{figure} \includegraphics[width=\textwidth]{diagrams/seeding_base.png} \end{figure} \end{column} \end{columns} \end{frame} \begin{frame}{Triplet Electron Seeding - Introduce Seed} \begin{columns} \begin{column}{0.45\textwidth} \begin{itemize} \item Now, examine, one-by-one seeds from general tracking* \item Note that we do not look at all hits in an event, but rather rely on general tracking to identify seeds. \end{itemize} \vspace{0.1in} \hline \vspace{0.1in} {\footnotesize *initialStepSeeds, highPtTripletStepSeeds, mixedTripletStepSeeds, pixelLessStepSeeds, tripletElectronSeeds, pixelPairElectronSeeds, stripPairElectronSeeds} \end{column} \begin{column}{0.55\textwidth} \begin{figure} \includegraphics[width=\textwidth]{diagrams/seeding_step1.png} \end{figure} \end{column} \end{columns} \end{frame} \begin{frame}{Triplet Electron Seeding - Match First Hit} \begin{columns} \begin{column}{0.5\textwidth} \begin{itemize} \item Using the beam spot, the SC position, and SC energy, propagate a path through the pixels. \item Next, require the first hit to be within a $\delta\phi$ and $\delta z$ window. ($\delta\phi$ and $\delta R$ for FPIX) \item $\delta z$ window for first hit is huge as SC and beam spot positions give very little information about $z$. \end{itemize} \end{column} \begin{column}{0.5\textwidth} \begin{figure} \includegraphics[width=\textwidth]{diagrams/seeding_step2.png} \end{figure} \end{column} \end{columns} \end{frame} \begin{frame}{Triplet Electron Seeding - Extrapolate Vertex} \begin{columns} \begin{column}{0.45\textwidth} \begin{itemize} \item Once we have a matched hit, use it with the SC position, to find the vertex z. \item Vertex x and y are still the beam spot's. \item Just a simple linear extrapolation. \end{itemize} \end{column} \begin{column}{0.55\textwidth} \begin{figure} \includegraphics[width=\textwidth]{diagrams/vertex_z.png} \end{figure} \end{column} \end{columns} \end{frame} \begin{frame}{Triplet Electron Seeding - Match Other Hits} \begin{columns} \begin{column}{0.45\textwidth} \begin{itemize} \item Now forget the SC position, and propagate a new track based on the vertex and first hit positions, and the SC energy. \item Progress one-by-one through the remaining hits in the seed and require each one fit within a specified window around the track. \item Quit when all hits are matched, or a hit falls outside the window. No skipping is allowed. \item However, \emph{layer} skipping is not ruled out if the original seed is missing a hit in a layer \end{itemize} \end{column} \begin{column}{0.55\textwidth} \begin{figure} \includegraphics[width=\textwidth]{diagrams/seeding_step3.png} \end{figure} \end{column} \end{columns} \end{frame} \begin{frame}{Triplet Electron Seeding - Window Sizes} \begin{columns} \begin{column}{0.55\textwidth} \begin{itemize} \item The $\delta\phi$ and $\delta R/z$ windows for each hit are defined using three parameters. \begin{itemize} \item \texttt{highEt} \item \texttt{highEtThreshold} \item \texttt{lowEtGradient} \end{itemize} \item From these, the window size is calculated as \\ $\texttt{highEt} + \min(0,\texttt{Et}-\texttt{highEtThreshold})*\texttt{lowEtGradient}$. \item For the first hit, these parameters for the $\delta \phi$ window are, \begin{itemize} \item $\texttt{highEt}=0.05$ \item $\texttt{highEtThreshold}=20$ \item $\texttt{lowEtGradient}=-0.002$ \end{itemize} \item For the first hit, these parameters for the $\delta \phi$ window are, \end{itemize} \end{column} \begin{column}{0.45\textwidth} \begin{figure} \includegraphics[width=\textwidth]{figures/dphi1_max.png} \end{figure} \end{column} \end{columns} \vspace{0.1in} \hrule \vspace{0.1in} These parameters can be specified for each successive hit, and in bins of $\eta$, so optimization is a challenge! \end{frame} \begin{frame}{Triplet Electron Seeding - Handle Missing Hits} \begin{columns} \begin{column}{0.45\textwidth} \begin{itemize} \item Finally, calculate the expected number of hits based on the number of working pixel modules the track passes through. \item Require exact$^1$ number of matched hits depending on the expected number of hits. \begin{itemize} \item If $N_{\textrm{exp}}=4$, require $N_{\textrm{match}}=3$ \item If $N_{\textrm{exp}}<4$, require $N_{\textrm{match}}=2$ \end{itemize} \item If the seed passes all requirements, all information, including \begin{itemize} \item Super cluster \item Original Seed \item Residuals (For both charge hypotheses) \end{itemize} are wrapped up and sent downstream to GSF tracking \end{itemize} \end{column} \begin{column}{0.55\textwidth} \begin{figure} \includegraphics[width=\textwidth]{diagrams/seeding_step4.png} \end{figure} \end{column} \end{columns} \vspace{0.1in} \hrule \vspace{0.1in} {\footnotesize $^1$Exact, rather than minimum to deal with duplicate seeds in input collection. Could switch to minimum with offline cross-cleaned seeds.} \end{frame} \begin{frame}{Outlook and Plans for 2018} \begin{itemize} \item Construct framework to measure efficiencies and fake-rates using MC-truth information. \item Use this framework to identify sources of inefficiency. \item Finally, optimize the window sizes for offline reconstruction. \end{itemize} \end{frame} \end{document}