Changeset 143 in svn
- Timestamp:
- Jan 7, 2009, 12:37:06 AM (16 years ago)
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- trunk/paper
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trunk/paper/notes.tex
r137 r143 91 91 A new framework, called \textsc{Delphes}~\cite{bib:Delphes}, is introduced here, for the fast simulation of a general purpose collider experiment. 92 92 Using the framework, observables can be estimated for specific signal and background channels, as well as their production and measurement rates, under a set of assumptions. 93 Starting from the output of event generators, the simulation of the detector response takes into account the subdetector resolutions, by smearing the kinematic alproperties of the visible final particles. Tracks of charged particles and calorimetric towers (or \textit{calotowers} are then created.93 Starting from the output of event generators, the simulation of the detector response takes into account the subdetector resolutions, by smearing the kinematics properties of the visible final particles. Tracks of charged particles and calorimetric towers (or \textit{calotowers} are then created. 94 94 95 95 \textsc{Delphes} includes the most crucial experimental features, like (1) the geometry of both central or forward detectors; (2) lepton isolation; (3) reconstruction of photons, leptons, jets, $b$-jets, $\tau$-jets and missing transverse energy; (4) trigger emulation and (5) an event display (Fig.~\ref{fig:FlowChart}). … … 99 99 %\includegraphics[width=0.9\textwidth]{FlowDelphes} 100 100 \includegraphics[scale=0.78]{FlowDelphes} 101 \caption{Flow chart describing the principles behind \textsc{Delphes}. Event files coming from external Monte Carlo generators are read by a convert or stage.102 The kinematic alvariables of the final state particles are then smeared according to the subdetector resolutions.101 \caption{Flow chart describing the principles behind \textsc{Delphes}. Event files coming from external Monte Carlo generators are read by a converter stage. 102 The kinematics variables of the final state particles are then smeared according to the subdetector resolutions. 103 103 Tracks are reconstructed in a simulated dipolar magnetic field and calorimetric towers sample the energy deposits. Based on these, dedicated algorithms are applied for particle identification, isolation and reconstruction. 104 104 The transport of very forward particle to the near-beam detectors is also simulated. 105 Finally, an output file is written, including generator level and analysis object data. If requested, a fully parametrisable trigger can be emulated. Option nally, the geometry and visualisation files for the 3D event display can also be produced.105 Finally, an output file is written, including generator level and analysis object data. If requested, a fully parametrisable trigger can be emulated. Optionally, the geometry and visualisation files for the 3D event display can also be produced. 106 106 All user parameters are set in the \textit{Smearing Card} and the \textit{Trigger Card}. } 107 107 \label{fig:FlowChart} … … 125 125 A central tracking system (\textsc{tracker}) is surrounded by an electromagnetic and a hadron calorimeters (\textsc{ecal} and \textsc{hcal}, resp.). Two forward calorimeters (\textsc{fcal}) ensure a larger geometric coverage for the measurement of the missing transverse energy. Finally, a muon system (\textsc{muon}) encloses the central detector volume 126 126 The fast simulation of the detector response takes into account geometrical acceptance of sub-detectors and their finite resolution, as defined in the smearing data card\footnote{\texttt{[code] }See the \texttt{RESOLution} class.}. 127 If no such file is provided, pred ifined values are used. The coverage of the various subsystems used in the default configuration are summarised in Tab.~\ref{tab:defEta}.127 If no such file is provided, predefined values are used. The coverage of the various subsystems used in the default configuration are summarised in Tab.~\ref{tab:defEta}. 128 128 129 129 \begin{table*}[t] … … 177 177 178 178 179 The particle four-momentum $p^\mu$ are smeared with a parametrisation directly derived from the detector tech inal designs\footnote{\texttt{[code] }The response of the detector is applied to the electromagnetic and the hadronic particles through the \texttt{SmearElectron} and \texttt{SmearHadron} functions.}.179 The particle four-momentum $p^\mu$ are smeared with a parametrisation directly derived from the detector technical designs\footnote{\texttt{[code] }The response of the detector is applied to the electromagnetic and the hadronic particles through the \texttt{SmearElectron} and \texttt{SmearHadron} functions.}. 180 180 In the default parametrisation, the calorimeter is assumed to cover the pseudorapidity range $|\eta|<3$ and consists in an electromagnetic and an hadronic part. Coverage between pseudorapidities of $3.0$ and $5.0$ is provided by forward calorimeters, with different response to electromagnetic objects ($e^\pm, \gamma$) or hadrons. 181 181 Muons and neutrinos are assumed no to interact with the calorimeters\footnote{In the current \textsc{Delphes} version, particles other than electrons ($e^\pm$), photons ($\gamma$), muons ($\mu^\pm$) and neutrinos ($\nu_e$, $\nu_\mu$ and $\nu_\tau$) are simulated as hadrons for their interactions with the calorimeters. The simulation of stable particles beyond the Standard Model should subsequently be handled with care.}. … … 229 229 As the detector is assumed to be symmetric in $\phi$ and with respect to the $\eta=0$ plane, the smearing card stores the number of calorimetric towers with $\phi=0$ and $\eta>0$ (default: $40$ towers). For a given $\eta$, the size of the $\phi$ segmentation is also specified. Fig.~\ref{fig:calosegmentation} illustrates the default segmentation of the $(\eta,\phi)$ plane. 230 230 231 232 233 231 \begin{figure}[!h] 234 232 \begin{center} … … 244 242 245 243 Most of the recent experiments in beam colliders have additional instrumentation along the beamline. These extend the $\eta$ coverage to higher values, for the detection of very forward final-state particles. 246 Zero Degree Calorimeters (\textsc{zdc}) are located at zero angle, i.e. are aligned with the beamline axis at the interaction point, and placed at the distance where the paths of incoming and outgoing beams separate (Fig.~\ref{fig:fdets}). These allow the measurement of stable neutral particles ($\gamma$ and $n$) coming from the interaction point, with large pseudorapi rities (e.g. $|\eta_{\textrm{n,}\gamma}| > 8.3$ in \textsc{cms}).247 Forward taggers (called here \textsc{rp220} and \textsc{fp420} as at the \textsc{lhc}) are meant for the measurement of particles following very closely the beam path. To be able to reach these detectors, such particles must have a charge identical to the beam particles, and a momentum very close to the nominal value for the beam. These taggers are near-beam detectors located a few millimet ers from the true beam trajectory and this distance defines their acceptance (Tab.~\ref{tab:fdetacceptance}).244 Zero Degree Calorimeters (\textsc{zdc}) are located at zero angle, i.e. are aligned with the beamline axis at the interaction point, and placed at the distance where the paths of incoming and outgoing beams separate (Fig.~\ref{fig:fdets}). These allow the measurement of stable neutral particles ($\gamma$ and $n$) coming from the interaction point, with large pseudorapidities (e.g. $|\eta_{\textrm{n,}\gamma}| > 8.3$ in \textsc{cms}). 245 Forward taggers (called here \textsc{rp220} and \textsc{fp420} as at the \textsc{lhc}) are meant for the measurement of particles following very closely the beam path. To be able to reach these detectors, such particles must have a charge identical to the beam particles, and a momentum very close to the nominal value for the beam. These taggers are near-beam detectors located a few millimetres from the true beam trajectory and this distance defines their acceptance (Tab.~\ref{tab:fdetacceptance}). 248 246 249 247 \begin{figure}[!h] … … 293 291 294 292 Analysis object data contain the final collections of particles ($e^\pm$, $\mu^\pm$, $\gamma$) or objects (light jets, $b$-jets, $\tau$-jets, $E_T^\textrm{miss}$) and are stored\footnote{\texttt{[code] }All these processed data are located under the \texttt{Analysis} tree.} in the output file created by \textsc{Delphes}. 295 In addition, some detector data are added: tracks, calor ometric towers and hits in \textsc{zdc}, \textsc{rp220} and \textsc{fp420}.293 In addition, some detector data are added: tracks, calorimetric towers and hits in \textsc{zdc}, \textsc{rp220} and \textsc{fp420}. 296 294 While electrons, muons and photons are easily identified, some other objects are more difficult to measure, like jets or missing energy due to invisible particles. 297 295 … … 324 322 325 323 A realistic analysis requires a correct treatment of final state particles which hadronise. Therefore, the most widely currently used jet algorithms have been integrated into the \textsc{Delphes} framework using the \textsc{FastJet} tools~\cite{bib:FastJet}. 326 Six different jet reconstruction schemes are available\footnote{\texttt{[code] }The choice is done by allocating the \texttt{JET\_jetalgo } input parameter in the smearing card.}. The first three belong to the cone algorithm class while the last three are using a sequential recombina ison scheme. For all of them, the towers are used as input of the jet clustering. Jet algorithms also differ with their sensitivity to soft particles or collinear splittings, and with their computing speed performance.324 Six different jet reconstruction schemes are available\footnote{\texttt{[code] }The choice is done by allocating the \texttt{JET\_jetalgo } input parameter in the smearing card.}. The first three belong to the cone algorithm class while the last three are using a sequential recombination scheme. For all of them, the towers are used as input of the jet clustering. Jet algorithms also differ with their sensitivity to soft particles or collinear splittings, and with their computing speed performance. 327 325 328 326 \subsubsection*{Cone algorithms} … … 336 334 In the following versions of \textsc{Delphes}, a new dedicated plug-in will be created on this purpose\footnote{\texttt{[code] }\texttt{JET\_coneradius} and \texttt{JET\_seed} variables in the smearing card.}. 337 335 338 \item {\it CDF MidPoint}~\cite{bib:midpoint}: Algorithm develop ped for the \textsc{cdf} Run II to reduce infrared and collinear sensitivity compared to purely seed-based cone by adding `midpoints' (energy barycenters) in the list of cone seeds.336 \item {\it CDF MidPoint}~\cite{bib:midpoint}: Algorithm developed for the \textsc{cdf} Run II to reduce infrared and collinear sensitivity compared to purely seed-based cone by adding `midpoints' (energy barycentres) in the list of cone seeds. 339 337 340 338 \item {\it Seedless Infrared Safe Cone}~\cite{bib:SIScone}: The \textsc{SISCone} algorithm is simultaneously insensitive to additional soft particles and collinear splittings, and fast enough to be used in experimental analysis. … … 397 395 398 396 Jets originating from $\tau$-decays are identified using an identification procedure consistent with the one applied in a full detector simulation~\cite{bib:cmsjetresolution}. 399 The tagging rely on two properties of the $\tau$ lepton. First, $77\%$ of the $\tau$ hadronic decays contain only one charged hadron associated to a few neutrals (Tab.~\ref{tab:taudecay}). Tracks are useful for this criteri um. Secondly, the particles arisen from the $\tau$ lepton produce narrow jets in the calorimeter (\textit{collimation}).397 The tagging rely on two properties of the $\tau$ lepton. First, $77\%$ of the $\tau$ hadronic decays contain only one charged hadron associated to a few neutrals (Tab.~\ref{tab:taudecay}). Tracks are useful for this criterion. Secondly, the particles arisen from the $\tau$ lepton produce narrow jets in the calorimeter (\textit{collimation}). 400 398 401 399 \begin{table}[!h] … … 539 537 Its quality and validity are assessed by comparing to resolution of the reconstructed data to the \textsc{cms} detector expectations. 540 538 541 Electrons and muons match by construction to the experiment designs, as the Gaussian smearing of their kinematic alproperties is defined according to the experiment resolution.539 Electrons and muons match by construction to the experiment designs, as the Gaussian smearing of their kinematics properties is defined according to the experiment resolution. 542 540 Similarly, the $b$-tagging efficiency (for real $b$-jets) and misidentification rates (for fake $b$-jets) are taken from the expected values of the experiment. 543 541 Unlike these simple objects, jets and missing transverse energy should be carefully cross-checked. … … 552 550 \end{equation} 553 551 The jets made of generator-level particles, or \textsc{mc} jets, are obtained by applying the same clustering algorithm to all particles considered as stable after hadronisation. 554 Jets produced by \textsc{Delphes} and satisfying the matching criteri umare called hereafter \textit{reconstructed jets}.552 Jets produced by \textsc{Delphes} and satisfying the matching criterion are called hereafter \textit{reconstructed jets}. 555 553 556 554 The ratio of the transverse energies of every reconstructed jet $E_T^\textrm{rec}$ and its corresponding \textsc{mc} jet $E_T^\textrm{MC}$ is calculated in each $\hat{p}_T$ bin. 557 The $E_T^\textrm{rec}/E_T^\textrm{MC}$ histogram is fitted with a Gaussian distribution in the interval \mbox{$\pm 2$~\textsc{rms}} cent ered around the mean value.555 The $E_T^\textrm{rec}/E_T^\textrm{MC}$ histogram is fitted with a Gaussian distribution in the interval \mbox{$\pm 2$~\textsc{rms}} centred around the mean value. 558 556 The resolution in each $\hat{p}_T$ bin is obtained by the fit mean $\langle x \rangle$ and variance $\sigma^2(x)$: 559 557 \begin{equation} … … 608 606 where the $\alpha$ parameter is depending on the resolution of the calorimeters. 609 607 610 The \textsc{met} resolution expected for the \textsc{cms} detector for similar events is $\sigma_x = (0.6-0.7) ~ (\Sigma E_T) ~ \mathrm{GeV}^{1/2}$ with no pile-up\footnote{\textit{Pile-up} events are extra simultaneous $pp$ collision occur ing at the same bunch crossing.}~\cite{bib:cmsjetresolution}.608 The \textsc{met} resolution expected for the \textsc{cms} detector for similar events is $\sigma_x = (0.6-0.7) ~ (\Sigma E_T) ~ \mathrm{GeV}^{1/2}$ with no pile-up\footnote{\textit{Pile-up} events are extra simultaneous $pp$ collision occurring at the same bunch crossing.}~\cite{bib:cmsjetresolution}. 611 609 The same quantity obtained by \textsc{Delphes} is in excellent agreement with the expectations of the general purpose detector, as $\alpha = 0.68$. 612 610 … … 651 649 % \end{figure} 652 650 653 Two and three-dimen tional representations of the detector configuration can be used for communication purpose, as it clearly shows the geometric coverage of the different detector subsystems. As an illustration, the generic detector geometry assumed in \textsc{Delphes} is shown in Fig.~\ref{fig:GenDet3}651 Two and three-dimensional representations of the detector configuration can be used for communication purpose, as it clearly shows the geometric coverage of the different detector subsystems. As an illustration, the generic detector geometry assumed in \textsc{Delphes} is shown in Fig.~\ref{fig:GenDet3} 654 652 %, \ref{fig:GenDet} 655 653 and~\ref{fig:GenDet2}. … … 667 665 668 666 Deeper understanding of interesting physics processes is possible by displaying the events themselves. 669 The visibility of each set of objects ($e^\pm$, $\mu^\pm$, $\tau^\pm$, jets, transverse missing energy) is enhanced by a colo r coding.670 Moreover, kinematic alinformation of each object is visible by a simple mouse action.667 The visibility of each set of objects ($e^\pm$, $\mu^\pm$, $\tau^\pm$, jets, transverse missing energy) is enhanced by a colour coding. 668 Moreover, kinematics information of each object is visible by a simple mouse action. 671 669 As an illustration, an associated photoproduction of a $W$ boson and a $t$ quark is shown in Fig.~\ref{fig:wt}. 672 670 This corresponds to a $pp(\gamma p \rightarrow Wt)pX$ process, where the $Wt$ couple is induced by an incoming photon emitted by one interacting proton~\cite{bib:wtphotoproduction}. … … 675 673 The experimental signature is a lack of hadronic activity in one forward hemisphere, where the surviving proton escapes. 676 674 The $t$ quark decays into a $W$ boson and a $b$ quark. 677 Both $W$ bosons decay into leptons ($W \rightarrow \mu \nu_\mu$ and $W \rightarrow \tau \nu_\tau$).678 The balance between the missing transverse energy and the charged lepton pair is clear, as well as the presence of an empty forward region. 679 675 Both $W$ bosons decay into leptons ($W \rightarrow \mu \nu_\mu$ and $W \rightarrow e \nu_e$). 676 The balance between the missing transverse energy and the charged lepton pair is clear, as well as the presence of an empty forward region. It is interesting to notice that the reconstruction algorithms build a fake $\tau$-jet around the electron. 677 680 678 \begin{figure}[!h] 681 679 \begin{center} 682 \includegraphics[width=\columnwidth]{Events_Delphes_1} 683 \caption{Example of $pp(\gamma p \rightarrow Wt)pY$ event, with $t \rightarrow Wb$. One $W$ boson decays into a $\mu \nu_\mu$ pair and the second one into a $\tau \nu_\tau$ pair. The surviving proton leaves a forward hemisphere with no hadronic activity. The isolated muon is shown as the blue vector. The $\tau$-jet is the cone around the green vector, while the reconstructed missing energy is shown in gray. One jet is visible in one forward region, along the beamline axis, opposite to the direction of the escaping proton.} 680 %\includegraphics[width=\columnwidth]{Events_Delphes_1} 681 \includegraphics[width=\columnwidth]{DisplayWt} 682 \caption{Example of $pp(\gamma p \rightarrow Wt)pY$ event, with $t \rightarrow Wb$. 683 One $W$ boson decays into a $\mu \nu_\mu$ pair and the second one into a $e \nu_e$ pair. 684 The surviving proton leaves a forward hemisphere with no hadronic activity. 685 The isolated muon is shown as the blue vector. 686 Around the electron, in red, is reconstructed a fake $\tau$-jet (green vector surrounded by a blue cone), while the reconstructed missing energy (in grey) is very small. One jet is visible in one forward region, along the beamline axis, opposite to the direction of the escaping proton.} 684 687 \label{fig:wt} 685 688 \end{center} 686 689 \end{figure} 690 691 For the comparison, Fig.~\ref{fig:gg} depicts an inclusive gluon pair production $pp \rightarrow ggX$. 692 The event final state contains more jets, in particular along the beam axis, which is expected as the interacting protons are destroyed by the collision. Two muon candidates and large missing transverse energy are also visible. 693 694 \begin{figure}[!h] 695 \begin{center} 696 %\includegraphics[width=\columnwidth]{Events_Delphes_1} 697 \includegraphics[width=\columnwidth]{Displayppgg} 698 \caption{Example of inclusive gluon pair production $pp \rightarrow ggX$. Many jets are visible in the event, in particular along the beam axis. Two muons (in blue) are produced and the missing transverse energy is significant in this event (grey vector).} 699 \label{fig:gg} 700 \end{center} 701 \end{figure} 702 687 703 688 704 \section{Conclusion and perspectives} … … 711 727 Moreover, the framework allows trigger emulation and 3D event visualisation. 712 728 713 \textsc{Delphes} has been develop ped using the parameters of the \textsc{cms} experiment but can be easily extended to \textsc{atlas} and other non-\textsc{lhc} experiments, as at Tevatron or at the \textsc{ilc}. Further developments include a more flexible design for the subdetector assembly and possibly the implementation of an event mixing module for pile-up event simulation.729 \textsc{Delphes} has been developed using the parameters of the \textsc{cms} experiment but can be easily extended to \textsc{atlas} and other non-\textsc{lhc} experiments, as at Tevatron or at the \textsc{ilc}. Further developments include a more flexible design for the subdetector assembly and possibly the implementation of an event mixing module for pile-up event simulation. 714 730 715 731 … … 717 733 \section*{Acknowledgements} 718 734 \addcontentsline{toc}{section}{Acknowledgements} 719 The authors would like to thank Vincent Lema\^itre, Muriel Vander Donckt and David d'Enterria for useful discussions and comments, and Loic Quertenmont for support in interfacing \textsc{Frog}. We are also really gr eatful to Alice Dechambre and Simon de Visscher for being beta testers of the complete package.735 The authors would like to thank Vincent Lema\^itre, Muriel Vander Donckt and David d'Enterria for useful discussions and comments, and Loic Quertenmont for support in interfacing \textsc{Frog}. We are also really grateful to Alice Dechambre and Simon de Visscher for being beta testers of the complete package. 720 736 Part of this work was supported by the Belgian Federal Office for Scientific, Technical and Cultural Affairs through the Interuniversity Attraction Pole P6/11. 721 737 … … 763 779 \section{User manual} 764 780 765 The available code is a zipped tar file which comes with everything needed to run the \textsc{Delphes} package, assuming a running .781 The available code is a zipped tar file which comes with everything needed to run the \textsc{Delphes} package, assuming a running \textsc{root} installation. 766 782 The package includes \texttt{ExRootAnalysis}~\cite{bib:ExRootAnalysis}, \textsc{Hector}~\cite{bib:Hector}, 767 783 \textsc{FastJet}~\cite{bib:FastJet}, and \textsc{Frog}~\cite{bib:Frog}, as well as the conversion codes to read standard \mbox{\textsc{s}td\textsc{hep}} input files (\texttt{mcfio} and \texttt{stdhep})~\cite{bib:mcfio}. … … 770 786 \subsection{Getting started} 771 787 772 In order to run \textsc{Delphes} on your system, first download is sources and compile it:\\ 788 In order to run \textsc{Delphes} on your system, first download its sources and compile it:\\ 789 \texttt{wget http://www.fynu.ucl.ac.be/users/s.ovyn/Delphes/files/Delphes\_V\_*.tar.gz}\\ 790 Replace the \texttt{*} symbol by the proper version number\footnote{Refer to the download page on the \textsc{Delphes} website \href{http://www.fynu.ucl.ac.be/users/s.ovyn/Delphes/download.html}{http://www.fynu.ucl.ac.be/users/s.ovyn/Delphes/download.html}.}. 791 773 792 \begin{quote} 774 793 \begin{verbatim} 775 me@mylap:~$ http://www.fynu.ucl.ac.be/users/s.ovyn/Delphes/files/Delphes_V_*.tar.gz 776 me@mylap:~$ tar -xvf Delphes_V_*.tar.gz 777 me@mylap:~$ cd Delphes_V_*.* 778 me@mylap:~$ ./genMakefile.tcl > Makefile 779 me@mylap:~$ make 794 me@mylaptop:~$ tar -xvf Delphes_V_*.tar.gz 795 me@mylaptop:~$ cd Delphes_V_*.* 796 me@mylaptop:~$ ./genMakefile.tcl > Makefile 797 me@mylaptop:~$ make 780 798 \end{verbatim} 781 \end{quote} 799 \end{quote} 800 Due to the large number of external utilities, the number of printed lines during the compilation can be high. 801 The user should not pay attention to possible warning messages. 802 When compilation is completed, the following message is printed: 803 \begin{quote} 804 \begin{verbatim} 805 me@mylaptop:~$ Delphes has been compiled 806 me@mylaptop:~$ Ready to run 807 \end{verbatim} 808 \end{quote} 809 782 810 \subsection{Running \textsc{Delphes} on your events} 783 811 784 In this chapter, we will explain how to use \textsc{Delphes} to perform a fast simulation of a general purpose detector on your event files. The first step to use \textsc{Delphes} is to create the list of input event files (e.g. {\verb inputlist.list }) file. As an important comment, don't forget that all the files comprised in the list file should have the same type (\texttt{*.hep}, \texttt{*.lhe} or \texttt{*.root}). In the simplest way of running \textsc{Delphes}, you need this input file and you need to specify the name of the output of \textsc{Delphes} that will contain the particle-level information ({\verb GEN } {\verb tree }), the analysis data objects after reconstruction ({\verb Analysis } {\verb tree }), and the results of the trigger emulation ({\verb Trigger } {\verb tree }).812 In this chapter, we will explain how to use \textsc{Delphes} to perform a fast simulation of a general purpose detector on your event files. The first step to use \textsc{Delphes} is to create the list of input event files (e.g. {\verb inputlist.list }). As an important comment, don't forget that all the files comprised in the list file should have the same type (\texttt{*.hep}, \texttt{*.lhe} or \texttt{*.root}). In the simplest way of running \textsc{Delphes}, you need this input file and you need to specify the name of the output file that will contain the generator-level data (\texttt{GEN} tree), the analysis data objects after reconstruction (\texttt{Analysis} tree), and the results of the trigger emulation (\texttt{Trigger} tree). 785 813 786 814 \begin{quote} … … 790 818 \end{quote} 791 819 792 \subsubsection{Setting the runconfiguration}820 \subsubsection{Setting up the configuration} 793 821 794 822 The program is driven by two datacards (default cards are {\verb data/DataCardDet.dat } and {\verb data/trigger.dat }) which allow a large spectrum of running conditions. 795 Please note that the either you provide those two datacards, either the running will be done using the default parameters defined in the constructor of the class {\verb RESOLution()}. If you chose a different detector or running configurationyou will need to edit the datacards accordingly.823 Please note that either the user provides these two datacards, either the running will be done using the default parameters defined in the constructor of the class \texttt{RESOLution}. If you choose a different detector or running configuration, you will need to edit the datacards accordingly. 796 824 797 825 \begin{enumerate} 798 826 799 \item{\bf The run card } 800 801 Contains all needed information to run \textsc{Delphes} 827 \item{\bf The smearing card } 828 829 The \textit{smearing} or \textit{run} card is by default \texttt{data/DataCard.dat}. 830 It contains all pieces of information needed to run \textsc{Delphes}: 802 831 \begin{itemize} 803 \item The following parameters are available: detector parameters, including calorimeter and tracking coverage and resolution, transverse energy thresholds allowed for reconstructed objects, jet algorithm to use as well as jetparameters.804 \item Four flags, {\verb FLAG_bfield }, {\verb FLAG_vfd }, {\verb FLAG_trigger } and {\verb FLAG_frog } should be assigned to decide if the magnetic field propagation, the very forward detectors acceptance, the trigger selection and the preparation for \textsc{Frog} display respectively are runningby \textsc{Delphes}.832 \item detector parameters, including calorimeter and tracking coverage and resolution, transverse energy thresholds for object reconstruction and jet algorithm parameters. 833 \item four flags ({\verb FLAG_bfield }, {\verb FLAG_vfd }, {\verb FLAG_trigger } and {\verb FLAG_frog }), which should be assigned if the magnetic field propagation, the very forward detectors simulation, the trigger selection and the preparation for \textsc{Frog} display (respectively) have to be run by \textsc{Delphes}. 805 834 \end{itemize} 806 835 807 If no datacard is provided ny the user, the default one is used that contains the followings smearing and running parameters:836 If no datacard is provided by the user, the default smearing and running parameters are used: 808 837 \begin{quote} 809 838 \begin{verbatim} 810 # Detector characteristics839 # Detector extension, in pseudorapidity units 811 840 CEN_max_tracker 2.5 // Maximum tracker coverage 812 841 CEN_max_calo_cen 3.0 // central calorimeter coverage … … 815 844 816 845 # Energy resolution for electron/photon 817 # \sigma/E = C + N/E + S/\sqrt{E} 846 # \sigma/E = C + N/E + S/\sqrt{E}, E in GeV 818 847 ELG_Scen 0.05 // S term for central ECAL 819 848 ELG_Ncen 0.25 // N term for central ECAL … … 824 853 825 854 # Energy resolution for hadrons in ecal/hcal/hf 826 # \sigma/E = C + N/E + S/\sqrt{E} 855 # \sigma/E = C + N/E + S/\sqrt{E}, E in GeV 827 856 HAD_Shcal 1.5 // S term for central HCAL 828 857 HAD_Nhcal 0. // N term for central HCAL … … 833 862 834 863 # Muon smearing 835 MU_SmearPt 0.01 864 MU_SmearPt 0.01 // transverse momentum Pt in GeV 836 865 837 866 # Tracking efficiencies 838 867 TRACK_ptmin 0.9 // minimal pT 839 TRACK_eff 100 // efficiency associated to the tracking 840 868 TRACK_eff 100 // efficiency associated to the tracking (%) 869 841 870 # Calorimetric towers 842 871 TOWER_number 40 … … 860 889 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 20 20 861 890 862 # Thresholds for reconstructed obje tcs891 # Thresholds for reconstructed objects, in GeV 863 892 PTCUT_elec 10.0 864 893 PTCUT_muon 10.0 … … 869 898 # General jet variable 870 899 JET_coneradius 0.7 // generic jet radius 871 JET_jetalgo 1 // Jet a glorithm selection872 JET_seed 1.0 // minimum seed to start jet reconstruction 873 874 # Tagging definition 875 BTAG_b 40 876 BTAG_mistag_c 10 877 BTAG_mistag_l 1 900 JET_jetalgo 1 // Jet algorithm selection 901 JET_seed 1.0 // minimum seed to start jet reconstruction, in GeV 902 903 # Tagging definition 904 BTAG_b 40 // b-tag efficiency (%) 905 BTAG_mistag_c 10 // mistagging (%) 906 BTAG_mistag_l 1 // mistagging (%) 878 907 879 908 # FLAGS … … 884 913 885 914 # In case BField propagation allowed 886 TRACK_radius 129 // radius of the BField coverage 887 TRACK_length 300 // length of the BField coverage 888 TRACK_bfield_x 0 // X composant of the BField 889 TRACK_bfield_y 0 // Y composant of the BField 890 TRACK_bfield_z 3.8 // Z composant of the BField 891 892 # In case Very forward detectors allowed 915 TRACK_radius 129 // radius of the BField coverage, in cm 916 TRACK_length 300 // length of the BField coverage, in cm 917 TRACK_bfield_x 0 // X composant of the BField, in T 918 TRACK_bfield_y 0 // Y composant of the BField, in T 919 TRACK_bfield_z 3.8 // Z composant of the BFieldn in T 920 921 # Very forward detector extension, in pseudorapidity 922 # if allowed 893 923 VFD_min_calo_vfd 5.2 // very forward calorimeter (if any) like CASTOR 894 924 VFD_max_calo_vfd 6.6 … … 906 936 \end{verbatim} 907 937 \end{quote} 908 938 In general, energies and momenta are expressed in GeV, and magnetic fields in T. 939 Geometrical extension are often referred in terms of pseudorapidity $\eta$, as the detectors are supposed to be symmetric in $\phi$. 909 940 910 941 \item{\bf The trigger card } 911 942 912 Contains the definition of all trigger bits. Cuts can be applied on the transverse momentum of electrons, muons, jets, tau-jets, photons and transverse missing energy. The following ``codename''should be used so that \textsc{Delphes} can correctly translate the input list of trigger bit into selection algorithms:943 This card contains the definitions of all trigger bits. Cuts can be applied on the transverse momentum $p_T$ of electrons, muons, jets, $\tau$-jets, photons and the missing transverse energy. The following codes should be used so that \textsc{Delphes} can correctly translate the input list of trigger bit into selection algorithms: 913 944 914 945 \begin{quote} 915 946 \begin{tabular}{ll} 916 {\it Trigger flag} & {\it Corresponding object}\\947 {\it Trigger code} & {\it Corresponding object}\\ 917 948 {\verb ELEC_PT } & electron \\ 918 949 {\verb MUON_PT } & muon \\ 919 950 {\verb JET_PT } & jet \\ 920 {\verb TAUJET_PT } & tau-jet \\921 {\verb ETMIS_PT } & transverse missingenergy \\951 {\verb TAUJET_PT } & $\tau$-jet \\ 952 {\verb ETMIS_PT } & missing transverse energy \\ 922 953 {\verb GAMMA_PT } & photon \\ 923 954 \end{tabular} 924 955 \end{quote} 925 956 926 Moreover, each line in the trigger datacard is allocated to exactly one trigger bit and start with the name of the correcponding trigger. Logical combinaison of several conditions is also possible. If the trigger bit uses the presence of multiple identical objects, the order of their thresholds is not meaningless: they must be defined in decreasing order. Finally, the different requirements on the objects must be separated by a {\verb && } flag. The default trigger card can be found in the data repository of \textsc{Delphes}. An exemple of trigger table consistent with the previous rules is given here:957 Each line in the trigger datacard is allocated to exactly one trigger bit and starts with the name of the corresponding trigger. Logical combination of several conditions is also possible. If the trigger bit requires the presence of multiple identical objects, the order of their $p_T$ thresholds is very important: they must be defined in \textit{decreasing} order. Finally, the different requirements on the objects must be separated by a {\verb && } flag. The default trigger card can be found in the data repository of \textsc{Delphes} (\texttt{data/trigger.dat}). An example of trigger table consistent with the previous rules is given here: 927 958 \begin{quote} 928 \begin{verbatim} DoubleElec >> ELEC_PT: '20' && ELEC_PT: '10' SingleElec and Single Muon >> ELEC_PT: '20' && MUON_PT: '15' 959 \begin{verbatim} 960 DoubleElec >> ELEC_PT: '20' && ELEC_PT: '10' 961 SingleElec and Single Muon >> ELEC_PT: '20' && MUON_PT: '15' 929 962 \end{verbatim} 930 963 \end{quote} … … 987 1020 \end{quote} 988 1021 989 In addition to their four-momentum and related quantities, additional properties are available for specific objects. Those are summari zed in the following table:1022 In addition to their four-momentum and related quantities, additional properties are available for specific objects. Those are summarised in the following table: 990 1023 \begin{quote} 991 1024 \begin{tabular}{ll} … … 1015 1048 \subsection{Running an analysis on your \textsc{Delphes} events} 1016 1049 1017 To analy ze the {\verb Root } {\verb TTree } ntuple of \textsc{Delphes}, the simplest way is to use the {\verb Analysis_Ex.cpp } code which is coming in the {\verb Examples } repository of \textsc{Delphes}. Note that all of this is optional and done to facilitate the analysis, as the output from \textsc{Delphes} is viewable with the standard TBrowser or \textsc{root} and can be analyzed using the MakeClass facility. To run the {\verb Examples/Analysis_Ex.cpp } code, the two following arguments are required: a text file containing the input \textsc{Delphes} root files to run, and the name of the output root file. To run the code:1050 To analyse the {\verb Root } {\verb TTree } ntuple of \textsc{Delphes}, the simplest way is to use the {\verb Analysis_Ex.cpp } code which is coming in the {\verb Examples } repository of \textsc{Delphes}. Note that all of this is optional and done to facilitate the analysis, as the output from \textsc{Delphes} is viewable with the standard TBrowser or \textsc{root} and can be analysed using the MakeClass facility. To run the {\verb Examples/Analysis_Ex.cpp } code, the two following arguments are required: a text file containing the input \textsc{Delphes} root files to run, and the name of the output root file. To run the code: 1018 1051 \begin{quote} 1019 1052 \begin{verbatim}
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