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Changeset 532 in svn

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Sep 18, 2009, 5:57:14 PM (15 years ago)

Author:

Xavier Rouby

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Update commentaires VL

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trunk/paper/CommPhysComp/notes.tex

-              r525
+              r532
 \ead{severine.ovyn@uclouvain.be}
+\author{X. Rouby\fnref{freiburg}}
+\fntext[freiburg]{Now in Physikalisches Institut, Albert-Ludwigs-Universit\"at Freiburg}
+\author{X. Rouby}
+%\author{X. Rouby\fnref{freiburg}}
+%\fntext[freiburg]{Now in Physikalisches Institut, Albert-Ludwigs-Universit\"at Freiburg}
 %\ead{xavier.rouby@cern.ch}
 …
 \begin{abstract}
+It is always delicate to  know whether theoretical predictions are visible and measurable in a high energy collider experiment due to the complexity of the related detectors, data acquisition chain and software.
+We introduce here a new \texttt{C++}-based framework, \textit{Delphes}, for fast simulation of
+a general-purpose experiment. The simulation includes a tracking system, embedded into a magnetic field, calorimetry and a muon
+system, and possible very forward detectors arranged along the beamline.
+The framework is interfaced to standard file formats (e.g.\ Les Houches Event File or \texttt{HepMC}) and outputs observable objects for analysis, like missing transverse energy and collections of electrons or jets.
+The simulation of detector response takes into account the detector resolution, and usual reconstruction algorithms, such as FastJet. A simplified preselection can also be applied on processed data for trigger emulation. Detection of very forward scattered particles relies on the transport in beamlines with the \textit{Hector} software. Finally, the \textsc{FROG} 2D/3D event display is used for visualisation of the collision final states.
+An overview of \textit{Delphes} is given as well as a few \textsc{LHC} use-cases for illustration.\\ \\
+% It is always delicate to  know whether theoretical predictions are visible and measurable in a high energy collider experiment due to the complexity of the related detectors, data acquisition chain and software.
+% We introduce here a new \texttt{C++}-based framework, \textit{Delphes}, for fast simulation of
+% a general-purpose experiment. The simulation includes a tracking system, embedded into a magnetic field, calorimetry and a muon
+% system, and possible very forward detectors arranged along the beamline.
+% The framework is interfaced to standard file formats (e.g.\ Les Houches Event File or \texttt{HepMC}) and outputs observable objects for analysis, like missing transverse energy and collections of electrons or jets.
+% The simulation of detector response takes into account the detector resolution, and usual reconstruction algorithms, such as FastJet. A simplified preselection can also be applied on processed data for trigger emulation. Detection of very forward scattered particles relies on the transport in beamlines with the \textit{Hector} software. Finally, the \textsc{FROG} 2D/3D event display is used for visualisation of the collision final states.
+% An overview of \textit{Delphes} is given as well as a few \textsc{LHC} use-cases for illustration.\\ \\
+It is sometimes difficult to know whether theoretical predictions can be observed in a high energy collider experiment, especially when expected experimental signature involve jets and missing transverse energy.
+For this purpose, we have designed a new \texttt{C++}-based framework, \textit{Delphes}, performing a fast multipurpose detector response simulation.
+The simulation includes a tracking system, embedded into a magnetic field, calorimeters and a muon system, and possible very forward detectors arranged along the beamline.
+The framework is interfaced to standard file formats (e.g.\ Les Houches Event File or \texttt{HepMC}) and outputs observables such as isolated leptons, missing transverse energy and collection of jets which can be used for dedicated analyses.
+The simulation of the detector response takes into account the effect of magnetic field, the granularity of the calorimeters and subdetector resolutions.
+A simplified preselection can also be applied on processed events for trigger emulation. Detection of very forward scattered particles relies on the transport in beamlines with the \textit{Hector} software. Finally, the \textsc{FROG} 2D/3D event display is used for visualisation of the collision final states.
+\\ \\
 \textit{Preprint:} \texttt{CP3-09-01}, \texttt{arXiv:0903.2225 [hep-ph]}\\ \\
 %\includegraphics[scale=0.8]{DELPHESLogoSml}\\
 …
 \section{Introduction}
+Experiments at high energy colliders are very complex systems for several reasons. Firstly, in terms of the various detector subsystems, including tracking, central calorimetry, forward calorimetry, and muon chambers. Such apparatus differ in their detection principles, technologies, geometrical acceptances, resolutions and sensitivities. Secondly, due to the requirement of a highly effective online selection (i.e.\ a \textit{trigger}), subdivided into several levels for an optimal reduction factor of ``uninteresting'' events, but based only on partially processed data. Finally, in terms of the experiment software, with different data formats (like \textit{raw} or \textit{reconstructed} data), many reconstruction algorithms and particle identification approaches.
+This complexity is handled by large collaborations of thousands of people, but the data and the expertise are only available to their members. Real data analyses require a full detector simulation, including transport of the primary and secondary particles through the detector material accounting for the various detector inefficiencies, the dead material, the imperfections and the geometrical details. Moreover, control of the detector calibration and alignment are crucial. Such simulation is very complicated, technical and requires a large \texttt{CPU} power. On the other hand, phenomenological studies, looking for the observability of given signals, may require only fast but realistic estimates of the expected signals and associated backgrounds.
+% Experiments at high energy colliders are very complex systems for several reasons. Firstly, in terms of the various detector subsystems, including tracking, central calorimetry, forward calorimetry, and muon chambers. Such apparatus differ in their detection principles, technologies, geometrical acceptances, resolutions and sensitivities. Secondly, due to the requirement of a highly effective online selection (i.e.\ a \textit{trigger}), subdivided into several levels for an optimal reduction factor of ``uninteresting'' events, but based only on partially processed data. Finally, in terms of the experiment software, with different data formats (like \textit{raw} or \textit{reconstructed} data), many reconstruction algorithms and particle identification approaches.
+Multipurpose detectors at high energy colliders are very complex systems. Their simulation is in general performed by means of the GEANT~\citep{bib:geant} package and final observables used for analyses usually require sophisticated reconstruction algorithms.
+This complexity is handled by large collaborations, and data and the expertise on reconstruction and simulation software are only available to their members. Precise data analyses require a full detector simulation, including transport of the primary and secondary particles through the detector material accounting for the various detector inefficiencies, the dead material, the imperfections and the geometrical details.
+%\textcolor{blue}{Moreover, control of the detector calibration and alignment are crucial}.
+Such simulation is very complicated, technical and requires a large \texttt{CPU} power. On the other hand, phenomenological studies, looking for the observability of given signals, may require only fast but realistic estimates of the expected signal signatures and their associated backgrounds.
 A new framework, called \textit{Delphes}~\citep{bib:delphes}, is introduced here, for the fast simulation of a general-purpose collider experiment.
 Using the framework, observables can be estimated for specific signal and background channels, as well as their production and measurement rates.
+Starting from the output of event generators, the simulation of the detector response takes into account the subdetector resolutions, by smearing the kinematic properties of the final-state particles\footnote{Throughout the paper, final-state particles refer as particles considered as stable by the event generator.}. Tracks of charged particles and deposits of energy in calorimetric cells (or \textit{calotowers}) are then created.
+Starting from the output of event generators, the simulation of the detector response takes into account the subdetector resolutions, by smearing the kinematic properties of the final-state particles (i.e. those considered as stable by the event generator
+\footnote{In the current \textit{Delphes} version, particles other than electrons ($e^\pm$), photons ($\gamma$), muons ($\mu^\pm$), neutrinos ($\nu_e$, $\nu_\mu$ and $\nu_\tau$) and neutralinos are simulated as hadrons for their interactions with the calorimeters. The simulation of stable particles beyond the Standard Model should therefore be handled with care~\citep{qr:invisibleparticles}.}). Tracks of charged particles and deposits of energy in calorimetric cells (or \textit{calotowers}) are then created. These two types of quantities are used for the reconstruction of jets and the isolation of leptons.
 \textit{Delphes} includes the most crucial experimental features, such as (Fig.~\ref{fig:FlowChart}):
 \begin{enumerate}
 \item the geometry of both central and forward detectors,
 \item magnetic field for tracks
+\item magnetic field for tracks and energy flow
 \item reconstruction of photons, leptons, jets, $b$-jets, $\tau$-jets and missing transverse energy,
 \item lepton isolation,
 …
 \caption{Flow chart describing the principles behind \textit{Delphes}. Event files coming from external Monte Carlo generators are read by a converter stage (top).
 The kinematics variables of the final-state particles are then smeared according to the tunable subdetector resolutions.
 Tracks are reconstructed in a simulated solenoidal magnetic field and calorimetric towers sample the energy deposits. Based on these low-level objects, dedicated algorithms are applied for particle identification, isolation and reconstruction.
+Tracks are reconstructed in a simulated solenoidal magnetic field and calorimetric cells sample the energy deposits. Based on these low-level objects, dedicated algorithms are applied for particle identification, isolation and reconstruction.
 The transport of very forward particles to the near-beam detectors is also simulated.
 Finally, an output file is written, including generator-level and analysis-object data.
 …
 Although this kind of approach yields much realistic results than a simple ``parton-level" analysis, a fast simulation comes with some limitations. Detector geometry is idealised, being uniform, symmetric around the beam axis, and having no cracks nor dead material. Secondary interactions, multiple scatterings, photon conversion and bremsstrahlung are also neglected.
+Four datafile formats can be used as input in \textit{Delphes}\footnote{\texttt{[code] }See the \texttt{HEPEVTConverter}, \texttt{HepMCConverter}, \texttt{LHEFConverter} and \texttt{STDHEPConverter} classes.}. In order to process events from many different generators, the standard Monte Carlo event structures \texttt{StdHEP}~\citep{bib:stdhep} and \texttt{HepMC}~\citep{bib:hepmc} can be used as an input. Besides, \textit{Delphes} can also provide detector response for events read in ``Les Houches Event Format'' (\textsc{LHEF}~\citep{bib:lhe}) and \texttt{*.root} files obtained from \texttt{*.hbook} using the \texttt{h2root} utility from the \textsc{ROOT} framework~\citep{bib:Root}.
+Several datafile formats can be used as input in \textit{Delphes} \citep{qr:inputformat},
+%\footnote{\texttt{[code] }See the \texttt{HEPEVTConverter}, \texttt{HepMCConverter}, \texttt{LHEFConverter} and \texttt{STDHEPConverter} classes.}.
+in order to process events from many different generators. The standard Monte Carlo event structures \texttt{StdHEP}~\citep{bib:stdhep} and \texttt{HepMC}~\citep{bib:hepmc} can be used as an input. Besides, \textit{Delphes} can also provide detector response for events read in ``Les Houches Event Format'' (\textsc{LHEF}~\citep{bib:lhe}) and \texttt{*.root} files obtained from \texttt{*.hbook} using the \texttt{h2root} utility from the \textsc{ROOT} framework~\citep{bib:Root}.
 %Afterwards, \textit{Delphes} performs a simple trigger simulation and reconstruct "high-level objects". These informations are organised in classes and each objects are ordered with respect to the transverse momentum.
 \textit{Delphes} uses the \texttt{ExRootAnalysis} utility~\citep{bib:ExRootAnalysis} to create output data in a \texttt{*.root} ntuple.
 This output contains a copy of the generator-level data (\texttt{GEN} tree), the analysis data objects after reconstruction (\texttt{Analysis} tree), and possibly the results of the trigger emulation (\texttt{Trigger} tree).
+In option\footnote{\texttt{[code]} See the \texttt{FLAG\_LHCO} variable in the detector datacard. This text file format is shortly described in the user manual.}, \textit{Delphes} can produce a reduced output file in \texttt{*.LHCO} text format, which is limited to the list of the reconstructed high-level objects in the final states.
+The program is driven by input cards. The detector card (\texttt{data/DetectorCard.dat}) allows a large spectrum of running conditions by modifying basic detector parameters, including calorimeter and tracking coverage and resolution, thresholds or jet algorithm parameters. The trigger card (\texttt{data/TriggerCard.dat}) lists the user algorithms for the simplified online preselection. Even if \textit{Delphes} has been developped for the simulation of general-purpose detectors at the \textsc{LHC} (namely, \textsc{CMS} and \textsc{ATLAS}), the input cards allow a flexible parametrisation for other cases, e.g.\ at future linear colliders.
+\section{Detector simulation}
+The overall layout of the general-purpose detector simulated by \textit{Delphes} is shown in Fig.~\ref{fig:GenDet3}.
+A central tracking system (\textsc{TRACKER}) is surrounded by an electromagnetic and a hadron calorimeters (\textsc{ECAL} and \textsc{HCAL}, resp., each with a central region and two endcaps). 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
+The fast simulation of the detector response takes into account geometrical acceptance of sub-detectors and their finite resolution, as defined in the detector data card\footnote{\texttt{[code] }See the \texttt{RESOLution} class.}.
+If no such file is provided, predefined values based on ``typical'' \textsc{CMS} acceptances and resolutions are used\footnote{\texttt{[code] }Detector and trigger cards for the \textsc{ATLAS} and \textsc{CMS} experiments are also provided in \texttt{data/} directory.}. The geometrical coverage of the various subsystems used in the default configuration are summarised in Tab.~\ref{tab:defEta}.
+\begin{table*}[t]
+In option
+%\footnote{\texttt{[code]} See the \texttt{FLAG\_LHCO} variable in the detector datacard. This text file format is shortly described in the user manual.},
+\textit{Delphes} can produce a reduced output file in \texttt{*.lhco} text format, which is limited to the list of the reconstructed high-level objects in the final states~\citep{qr:lhco}.
+\section{Simulation of the detector response}
+The overall layout of the multipurpose detector simulated by \textit{Delphes} is shown in Fig.~\ref{fig:GenDet3}.
+It consists in a central tracking system (\textsc{TRACKER}) surrounded by an electromagnetic and a hadron calorimeters (\textsc{ECAL} and \textsc{HCAL}, each with a central region and two endcaps). 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.
+A detector card \citep{qr:detectorcard} allows a large spectrum of running conditions by modifying basic detector parameters, including calorimeter and tracking coverage and resolution, thresholds or jet algorithm parameters.
+Even if \textit{Delphes} has been developped for the simulation of general-purpose detectors at the \textsc{LHC} (namely, \textsc{CMS} and \textsc{ATLAS}), this input parameter file interfaces a flexible parametrisation for other cases, e.g.\ at future linear colliders~\citep{qr:datacards}.
+If no detector card is provided, predefined values based on ``typical'' \textsc{CMS} acceptances and resolutions are used.
+%\footnote{\texttt{[code] }Detector and trigger cards for the \textsc{ATLAS} and \textsc{CMS} experiments are also provided in \texttt{data/} directory.}.
+The geometrical coverage of the various subsystems used in the default configuration are summarised in Tab.~\ref{tab:defEta}.
+\begin{table}[t]
+% \begin{table*}[t]
 \begin{center}
 \caption{Default extension in pseudorapidity $\eta$ of the different subdetectors.
 Full azimuthal ($\phi$) acceptance is assumed.
+The corresponding parameter name, in the detector card, is given. \vspace{0.5cm}}
+\begin{tabular}{llcc}
+ \vspace{0.5cm}}
+% \begin{tabular}{llcc}
+% \hline
+% Subdetector & & $\eta$ & $\phi$ \\
+% \textsc{TRACKER}      & {\verb CEN_max_tracker }      & $[-2.5; 2.5]$         & $[-\pi ; \pi]$\\
+% \textsc{ECAL}, \textsc{HCAL} & {\verb CEN_max_calo_cen }& $[-1.7 ; 1.7]$      & $[-\pi ; \pi]$\\
+% \textsc{ECAL}, \textsc{HCAL} endcaps & {\verb CEN_max_calo_ec }& $[-3 ; -1.7] \& [1.7 ; 3]$   & $[-\pi ; \pi]$\\
+% \textsc{FCAL}                 & {\verb CEN_max_calo_fwd }     & $[-5 ; -3]$ \& $[3 ;5]$     & $[-\pi ; \pi]$\\
+% \textsc{MUON}                 & {\verb CEN_max_mu }           & $[-2.4 ; 2.4]$        & $[-\pi ; \pi]$\\ \hline
+% \end{tabular}
+\begin{tabular}{lcc}
 \hline
+Subdetector & & $\eta$ & $\phi$ \\
 \textsc{TRACKER}        & {\verb CEN_max_tracker }      & $[-2.5; 2.5]$         & $[-\pi ; \pi]$\\
 \textsc{ECAL}, \textsc{HCAL} & {\verb CEN_max_calo_cen }& $[-1.7 ; 1.7]$        & $[-\pi ; \pi]$\\
 \textsc{ECAL}, \textsc{HCAL} endcaps & {\verb CEN_max_calo_ec }& $[-3 ; -1.7] \& [1.7 ; 3]$     & $[-\pi ; \pi]$\\
 \textsc{FCAL}           & {\verb CEN_max_calo_fwd }     & $[-5 ; -3]$ \& $[3 ;5]$     & $[-\pi ; \pi]$\\
 \textsc{MUON}           & {\verb CEN_max_mu }           & $[-2.4 ; 2.4]$        & $[-\pi ; \pi]$\\ \hline
+ & $\eta$ & $\phi$ \\ \hline
+\textsc{TRACKER}        & $[-2.5; 2.5]$                 & $[-\pi ; \pi]$\\
+\textsc{ECAL}, \textsc{HCAL} & $[-1.7 ; 1.7]$           & $[-\pi ; \pi]$\\
+\textsc{ECAL}, \textsc{HCAL} endcaps & $[-3 ; -1.7]$ \& $[1.7 ; 3]$     & $[-\pi ; \pi]$\\
+\textsc{FCAL}           & $[-5 ; -3]$ \& $[3 ;5]$       & $[-\pi ; \pi]$\\
+\textsc{MUON}           & $[-2.4 ; 2.4]$                & $[-\pi ; \pi]$\\ \hline
 \end{tabular}
 \label{tab:defEta}
 \end{center}
+\end{table*}
+% \end{table*}
+\end{table}
 \begin{figure}[!ht]
 …
+\subsubsection*{Magnetic field}
+In addition to the subdetectors, the effects of a solenoidal magnetic field are simulated for the charged particles\footnote{\texttt{[code] }See the \texttt{TrackPropagation} class.}. This affects the position at which charged particles enter the calorimeters and their corresponding tracks. The field extension is limited to the tracker volume and is in particular not applied for muon chambers. Howerver, this is not a limiting factor as the resolution applied for muon reconstruction is the one expected by the experiment, which consequently includes the effects of the magnetic field within the muon system.
+\subsection{Magnetic field}
+In addition to the subdetectors, the effects of a solenoidal magnetic field are simulated for the charged particles~\citep{qr:magneticfield}
+%\footnote{\texttt{[code] }See the \texttt{TrackPropagation} class.}
+. This affects the position at which charged particles enter the calorimeters and their corresponding tracks. The field extension is limited to the tracker volume and is in particular not applied for muon chambers. Howerver, this is not a limiting factor as the resolution applied for muon reconstruction is the one expected by the experiment, which consequently includes the effects of the magnetic field within the muon system.
 \subsection{Tracks reconstruction}
 Every stable charged particle with a transverse momentum above some threshold and lying inside the detector volume covered by the tracker provides a track.
+By default, a track is assumed to be reconstructed with $90\%$ probability\footnote{\texttt{[code]} The reconstruction efficiency is defined in the detector datacard by the \texttt{TRACKING\_EFF} term.} if its transverse momentum $p_T$ is higher than $0.9~\textrm{GeV}/c$ and if its pseudorapidity $|\eta| \leq 2.5$.
+\subsection{Simulation of central calorimeters}
+The energy of each particle considered as stable in the generator particle list is smeared, with a Gaussian distribution depending on the calorimeter resolution. This resolution varies with the sub-calorimeter (\textsc{ECAL}, \textsc{HCAL}, \textsc{FCAL}) measuring the particle.
+The response of each sub-calorimeter is parametrised as a function of the energy:
+By default, a track is assumed to be reconstructed with $90\%$ probability
+%\footnote{\texttt{[code]} The reconstruction efficiency is defined in the detector datacard by the \texttt{TRACKING\_EFF} term.}
+if its transverse momentum $p_T$ is higher than $0.9~\textrm{GeV}/c$ and if its pseudorapidity
+$|\eta| \leq 2.5$~\citep{qr:tracks}. No smearing is currently applied on tracks.
+\subsection{Calorimetric cells}
+The response of the calorimeters to energy deposits of incoming particles depends on their segmentation and resolution. In CMS and ATLAS detectors, for instance, the calorimeter characteristics are not identical in every direction, with typically finer resolution and granularity in the central regions~\citep{bib:cmsjetresolution,bib:ATLASresolution}. It is thus very important to compute the exact coordinates of the entry point of the particles into the calorimeters, via the magnetic field calculations.
+The response of each sub-calorimeter is parametrised through a Gaussian smearing of the particle energy with a variance $\sigma$:
 \begin{equation}
 \frac{\sigma}{E} = \frac{S}{\sqrt{E}} \oplus \frac{N}{E} \oplus C,
 \label{eq:caloresolution}
 \end{equation}
+where $S$, $N$ and $C$ are the \textit{stochastic}, \textit{noise} and \textit{constant} terms, respectively, and $\oplus$ stands for quadratic additions.\\
+The particle four-momentum $p^\mu$ are smeared with a parametrisation directly derived from typical 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.} \citep{bib:cmsjetresolution,bib:ATLASresolution}.
+where $S$, $N$ and $C$ are the \textit{stochastic}, \textit{noise} and \textit{constant} terms, respectively, and $\oplus$ stands for quadratic additions~\citep{qr:energysmearing}.\\
+%\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.}
 In the default parametrisation, the calorimeter is assumed to cover the pseudorapidity range $|\eta|<3$ and consists in an electromagnetic and hadronic parts. 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.
+Muons and neutrinos are assumed not to interact with the calorimeters\footnote{In the current \textit{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 therefore be handled with care.}.
+Muons and neutrinos are assumed not to interact with the calorimeters~\citep{qr:invisibleparticles}.
+%\footnote{In the current \textit{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 therefore be handled with care.}.
 The default values of the stochastic, noise and constant terms are given in Tab.~\ref{tab:defResol}.\\
 \begin{table}[!h]
 \begin{center}
+\caption{Default values for the resolution of the central and forward calorimeters. Resolution is parametrised by the \textit{stochastic} ($S$), \textit{noise} ($N$) and \textit{constant} ($C$) terms (Eq.~\ref{eq:caloresolution}).
+The corresponding parameter name, in the detector card, is given. \vspace{0.5cm}}
+\begin{tabular}[!h]{lllc}
+\caption{Default values for the resolution of the central and forward calorimeters (for both electromagnetic and hadronic parts). Resolution is parametrised by the \textit{stochastic} ($S$), \textit{noise} ($N$) and \textit{constant} ($C$) terms (Eq.~\ref{eq:caloresolution})~\citep{qr:resolutionterms}.
+%The corresponding parameter name, in the detector card, is given.
+\vspace{0.5cm}}
+\begin{tabular}[!h]{lccc}
 \hline
+\multicolumn{2}{c}{Resolution Term}   & Card flag & Value\\\hline
+ \multicolumn{4}{l}{\textsc{ECAL}} \\
+        & $S$ (GeV$^{1/2}$) & {\verb ELG_Scen }  & $0.05$ \\
+        & $N$ (GeV)& {\verb ELG_Ncen }  & $0.25$ \\
+        & $C$ & {\verb ELG_Ccen }  & $0.0055$ \\
+ \multicolumn{4}{l}{\textsc{ECAL}, end caps} \\
+        & $S$ (GeV$^{1/2}$) & {\verb ELG_Sec }  & $0.05$ \\
+        & $N$ (GeV)& {\verb ELG_Nec }  & $0.25$ \\
+        & $C$ & {\verb ELG_Cec }  & $0.0055$ \\
+ \multicolumn{4}{l}{\textsc{FCAL}, electromagnetic part} \\
+        & $S$ (GeV$^{1/2}$)& {\verb ELG_Sfwd }  & $2.084$ \\
+        & $N$ (GeV)& {\verb ELG_Nfwd }  & $0$ \\
+        & $C$ & {\verb ELG_Cfwd }  & $0.107$ \\
+ \multicolumn{4}{l}{\textsc{HCAL}} \\
+        & $S$ (GeV$^{1/2}$)& {\verb HAD_Scen } & $1.5$ \\
+        & $N$ (GeV)& {\verb HAD_Ncen } & $0$\\
+        & $C$ & {\verb HAD_Ccen } & $0.05$\\
+ \multicolumn{4}{l}{\textsc{HCAL}, end caps} \\
+        & $S$ (GeV$^{1/2}$)& {\verb HAD_Sec } & $1.5$ \\
+        & $N$ (GeV)& {\verb HAD_Nec } & $0$\\
+        & $C$ & {\verb HAD_Cec } & $0.05$\\
+ \multicolumn{4}{l}{\textsc{FCAL}, hadronic part} \\
+        & $S$ (GeV$^{1/2}$)& {\verb HAD_Sfwd }   & $2.7$\\
+        & $N$ (GeV)& {\verb HAD_Nfwd }   & $0$ \\
+        & $C$ & {\verb HAD_Cfwd }   & $0.13$\\
+%\multicolumn{2}{c}{Resolution Term}   & Value\\\hline
+        & $S$ (GeV$^{1/2}$) & $N$ (GeV) & $C$ \\\hline
+ %\multicolumn{4}{l}{\textsc{ECAL}} \\
+  ECAL            & $0.05$   & $0.25$ & $0.0055$ \\
+ %\multicolumn{4}{l}{\textsc{ECAL}, end caps} \\
+  ECAL, end caps  & $0.05$  & $0.25$ & $0.0055$ \\
+ %\multicolumn{4}{l}{\textsc{FCAL}, electromagnetic part} \\
+  FCAL, e.m. part & $2.084$ & $0$    & $0.107$ \\
+ %\multicolumn{4}{l}{\textsc{HCAL}} \\
+  HCAL            & $1.5$   & $0$    & $0.05$\\
+ %\multicolumn{4}{l}{\textsc{HCAL}, end caps} \\
+  HCAL, end caps  & $1.5$   & $0$    & $0.05$\\
+ %\multicolumn{4}{l}{\textsc{FCAL}, hadronic part} \\
+  FCAL, had. part & $2.7$   & $0$    & $0.13$\\
 \hline
 \end{tabular}
 …
 \end{table}
+The energy of electrons and photons found in the particle list are smeared using the \textsc{ECAL} resolution terms. Charged and neutral final-state hadrons interact with the \textsc{ECAL}, \textsc{HCAL} and \textsc{FCAL}.
+Some long-living particles, such as the $K^0_s$ and $\Lambda$'s, with lifetime $c\tau$ smaller than $10~\textrm{mm}$ are considered as stable particles although they decay before the calorimeters. The energy smearing of such particles is performed using the expected fraction of the energy, determined according to their decay products, that would be deposited into the \textsc{ECAL} ($E_{\textsc{ECAL}}$) and into the \textsc{HCAL} ($E_{\textsc{HCAL}}$). Defining $F$ as the fraction of the energy leading to a \textsc{HCAL} deposit, the two energy values are given by
+% \begin{table}[!h]
+% \begin{center}
+% \caption{Default values for the resolution of the central and forward calorimeters. Resolution is parametrised by the \textit{stochastic} ($S$), \textit{noise} ($N$) and \textit{constant} ($C$) terms (Eq.~\ref{eq:caloresolution}).
+% The corresponding parameter name, in the detector card, is given. \vspace{0.5cm}}
+% \begin{tabular}[!h]{lllc}
+% \hline
+% \multicolumn{2}{c}{Resolution Term}   & Card flag & Value\\\hline
+%  \multicolumn{4}{l}{\textsc{ECAL}} \\
+%       & $S$ (GeV$^{1/2}$) & {\verb ELG_Scen }  & $0.05$ \\
+%         & $N$ (GeV)& {\verb ELG_Ncen }  & $0.25$ \\
+%         & $C$ & {\verb ELG_Ccen }  & $0.0055$ \\
+%  \multicolumn{4}{l}{\textsc{ECAL}, end caps} \\
+%         & $S$ (GeV$^{1/2}$) & {\verb ELG_Sec }  & $0.05$ \\
+%         & $N$ (GeV)& {\verb ELG_Nec }  & $0.25$ \\
+%         & $C$ & {\verb ELG_Cec }  & $0.0055$ \\
+%  \multicolumn{4}{l}{\textsc{FCAL}, electromagnetic part} \\
+%         & $S$ (GeV$^{1/2}$)& {\verb ELG_Sfwd }  & $2.084$ \\
+%         & $N$ (GeV)& {\verb ELG_Nfwd }  & $0$ \\
+%         & $C$ & {\verb ELG_Cfwd }  & $0.107$ \\
+%  \multicolumn{4}{l}{\textsc{HCAL}} \\
+%         & $S$ (GeV$^{1/2}$)& {\verb HAD_Scen } & $1.5$ \\
+%         & $N$ (GeV)& {\verb HAD_Ncen } & $0$\\
+%         & $C$ & {\verb HAD_Ccen } & $0.05$\\
+%  \multicolumn{4}{l}{\textsc{HCAL}, end caps} \\
+%         & $S$ (GeV$^{1/2}$)& {\verb HAD_Sec } & $1.5$ \\
+%         & $N$ (GeV)& {\verb HAD_Nec } & $0$\\
+%         & $C$ & {\verb HAD_Cec } & $0.05$\\
+%  \multicolumn{4}{l}{\textsc{FCAL}, hadronic part} \\
+%         & $S$ (GeV$^{1/2}$)& {\verb HAD_Sfwd }   & $2.7$\\
+%         & $N$ (GeV)& {\verb HAD_Nfwd }   & $0$ \\
+%         & $C$ & {\verb HAD_Cfwd }   & $0.13$\\
+% \hline
+% \end{tabular}
+% \label{tab:defResol}
+% \end{center}
+% \end{table}
+The energy of electrons and photons found in the particle list are smeared using only the \textsc{ECAL} resolution terms, while charged and neutral final-state hadrons interact with all calorimeters.
+Some long-living particles, such as the $K^0_s$ and $\Lambda$'s, with lifetime $c\tau$ smaller than $10~\textrm{mm}$ are considered as stable particles by the generators although they decay before the calorimeters. The energy smearing of such particles is performed using the expected fraction of the energy, determined according to their decay products, that would be deposited into the \textsc{ECAL} ($E_{\textsc{ECAL}}$) and into the \textsc{HCAL} ($E_{\textsc{HCAL}}$). Defining $F$ as the fraction of the energy leading to a \textsc{HCAL} deposit, the two energy values are given by
 \begin{equation}
 \left\{
 …
 \end{equation}
 where $0 \leq F \leq 1$. The electromagnetic part is handled the same way for the electrons and photons.
 The resulting calorimetry energy measurement given after the application of the smearing is then $E = E_{\textsc{HCAL}} + E_{\textsc{ECAL}}$. For $K_S^0$ and $\Lambda$ hadrons\footnote{\texttt{[code]} To implement different ratios for other particles, see the \texttt{BlockClasses} class.}, the energy fraction is $F$ is assumed to be $0.7$.\\
+\subsection{Calorimetric towers}
 The smallest unit for geometrical sampling of the calorimeters is a \textit{tower}; it segments the $(\eta,\phi)$ plane for the energy measurement. No longitudinal segmentation is available in the simulated calorimeters. All undecayed particles, except muons and neutrinos deposit energy in a calorimetric tower, either in \textsc{ECAL}, in \textsc{HCAL} or \textsc{FCAL}.
 As the detector is assumed to be cylindrical (e.g.\ symmetric in $\phi$ and with respect to the $\eta=0$ plane), the detector 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 calorimeter segmentation, which is common for the electromagnetic and hadronic sections at a given $(\eta,\phi)$.
+The resulting calorimetry energy measurement given after the application of the smearing is then $E = E_{\textsc{HCAL}} + E_{\textsc{ECAL}}$. For $K_S^0$ and $\Lambda$ hadrons
+%\footnote{\texttt{[code]} To implement different ratios for other particles, see the \texttt{BlockClasses} class.}
+, the energy fraction is $F$ is assumed to be $0.7$~\citep{qr:emhadratios}.\\
+The smallest unit for geometrical sampling of the calorimeters is a \textit{cell}; it segments the $(\eta,\phi)$ plane for the energy measurement. No longitudinal segmentation is available in the simulated calorimeters. \textit{Delphes} assumes that ECAL and HCAL have the same segmentations and that the detector is symmetric in $\phi$ and with respect to the $\eta=0$ plane~\citep{qr:calorimetriccells}.
+Fig.~\ref{fig:calosegmentation} illustrates the default calorimeter segmentation.
 \begin{figure}[!ht]
 …
 \end{figure}
+The calorimetric towers directly enter in the calculation of the missing transverse energy (\textsc{MET}), and as input for the jet reconstruction algorithms. No sharing between neighbouring towers is implemented when particles enter a tower very close to its geometrical edge. Smearing is applied directly on the accumulated electromagnetic and hadronic energies of each calorimetric tower.
+\subsection{Very forward detector simulation}
+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. In \textit{Delphes}, Zero Degree Calorimeters, roman pots and forward taggers have been implemented (Fig.~\ref{fig:fdets}).
+\begin{figure}[!ht]
+\begin{center}
+%\includegraphics[width=\columnwidth]{fdets}
+\includegraphics[width=\columnwidth]{fig4}
+\caption{Default location of the very forward detectors, including \textsc{ZDC}, \textsc{RP220} and \textsc{FP420} in the \textsc{LHC} beamline.
+Incoming (beam 1, red) and outgoing (beam 2, black) beams on one side of the fifth interaction point (\textsc{IP5}, $s=0~\textrm{m}$ on the plot).
+The Zero Degree Calorimeter is located in perfect alignment with the beamline axis at the interaction point, at $140~\textrm{m}$, the beam paths are separated. The forward taggers are near-beam detectors located at $220~\textrm{m}$ and $420~\textrm{m}$. Beamline simulation with \textit{Hector}~\citep{bib:hector}. All very forward detectors are located symmetrically around the interaction point. }
+\label{fig:fdets}
+\end{center}
+\end{figure}
+\begin{table*}[t]
+\begin{center}
+\caption{Default parameters for the forward detectors: distance from the interaction point and detector acceptance. The \textsc{LHC} beamline is assumed around the fifth \textsc{LHC} interaction point (\textsc{IP}). For the \textsc{ZDC}, the acceptance depends only on the pseudorapidity $\eta$ of the particle, which should be neutral and stable.
+The tagger acceptance is fully determined by the distance in the transverse plane of the detector to the real beam position~\citep{bib:hector}. It is expressed in terms of the particle energy ($E$).
+All detectors are located on both sides of the interaction point.
+\vspace{0.5cm}}
+\begin{tabular}{llcl}
+\hline
+Detector & Distance from \textsc{IP}& Acceptance & \\ \hline
+\textsc{ZDC}   & $\pm 140$ m & $|\eta|> 8.3$       & for $n$ and $\gamma$\\
+\textsc{RP220} & $\pm 220$ m & $E \in [6100 ; 6880]$ (GeV) & at $2~\textrm{mm}$\\
+\textsc{FP420} & $\pm 420$ m & $E \in [6880 ; 6980]$ (GeV) & at $4~\textrm{mm}$\\
+\hline
+\end{tabular}
+\label{tab:fdetacceptance}
+\end{center}
+\end{table*}
+\subsubsection*{Zero Degree Calorimeters}
+In direct sight of the interaction point, on both sides of the central detector, the Zero Degree Calorimeters (\textsc{ZDC}s) are located at zero angle, i.e.\ are aligned with the beamline axis at the interaction point. They are placed beyond the point where the paths of incoming and outgoing beams separate. 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{ATLAS} and \textsc{CMS}).
+The trajectory of the neutrals observed in the \textsc{ZDC}s is a straight line, while charged particles are deflected away from their acceptance window by the powerful magnets located in front of them. The fact that additional charged particles may enter the \textsc{ZDC} acceptance is neglected here.
+The \textsc{ZDC}s have the ability to measure the time-of-flight of the particle.
+This corresponds to the delay after which the particle is observed in the detector, with respect to the bunch crossing reference time at the interaction point ($t_0$). The measured time-of-flight $t$ is simply given by:
+\begin{equation}
+ t = t_0 + \frac{1}{v} \times \Big( \frac{s-z}{\cos \theta}\Big),
+\end{equation}
+where $t_0$ is thus the true time coordinate of the vertex from which the particle originates, $v$ the particle velocity, $s$ is the \textsc{ZDC} distance to the interaction point, $z$ is the longitudinal coordinate of the vertex, $\theta$ is the particle emission angle. It is then assumed that the neutral particle observed in the \textsc{ZDC} is highly relativistic, i.e.\ travelling at the speed of light $c$. We also assume that $\cos \theta = 1$, i.e.\ $\theta \approx 0$ or equivalently $\eta$ is large. As an example, $\eta = 5$ leads to $\theta = 0.013$ and $1 - \cos \theta < 10^{-4}$.
+The formula then reduces to
+\begin{equation}
+ t = \frac{1}{c} \times (s-z).
+\end{equation}
+For example, a photon takes $0.47~\mu\textrm{s}$ to reach a \textsc{ZDC} located at $s=140~\textrm{m}$, neglecting $z$ and $\theta$. For the time-of-flight measurement, a Gaussian smearing can be applied according to the detector resolution (Tab.~\ref{tab:defResolZdc}). In the current version of \textit{Delphes}, only neutrons, antineutrons and photons are assumed to be able to reach the \textsc{ZDC}s, all other particles being neglected.
+The \textsc{ZDC}s are composed of an electromagnetic and a hadronic sections, for the measurement of photons and neutrons, respectively. The energy of the observed neutral is smeared according to Eq.~\ref{eq:caloresolution} and the corresponding section resolutions (Tab.~\ref{tab:defResolZdc}). The \textsc{ZDC} hits do not enter in the calorimeter tower list used for reconstruction of jets and missing transverse energy.
+\begin{table}[!h]
+\begin{center}
+\caption{Default values for the resolution of the zero degree calorimeters. Resolution on energy measurement is parametrised by the \textit{stochastic} ($S$), \textit{noise} ($N$) and \textit{constant} ($C$) terms (Eq.~\ref{eq:caloresolution}). The time-of-flight is smeared according to a Gaussian function.
+The corresponding parameter name, in the detector card, is given. \vspace{0.5cm}}
+\begin{tabular}[!h]{lllc}
+\hline
+\multicolumn{2}{c}{Resolution Term}   & Card flag & Value\\\hline
+ \multicolumn{4}{l}{\textsc{ZDC}, electromagnetic part} \\
+        & $S$ (GeV$^{1/2}$)& \texttt{ELG\_Szdc}  & $0.7$ \\
+        & $N$ (GeV)& \texttt{ELG\_Nzdc}  & $0.0$ \\
+        & $C$ & \texttt{ELG\_Czdc}  & $0.08$ \\
+ \multicolumn{4}{l}{\textsc{ZDC}, hadronic part} \\
+        & $S$ (GeV$^{1/2}$)& \texttt{HAD\_Szdc}   & $1.38$\\
+        & $N$ (GeV)& \texttt{HAD\_Nzdc}   & $0$ \\
+        & $C$ & \texttt{HAD\_Czdc}   & $0.13$\\
+ \multicolumn{4}{l}{\textsc{ZDC}, timing resolution} \\
+        & $\sigma_t$ (s) & \texttt{ZDC\_T\_resolution} & $0$ \\
+\hline
+\end{tabular}
+\label{tab:defResolZdc}
+\end{center}
+\end{table}
+\subsubsection*{Forward taggers}
+Forward taggers (called here \textsc{RP220}, for ``roman pots at $220~\textrm{m}$'' and \textsc{FP420} ``for forward proton taggers at $420~\textrm{m}$'', as at the \textsc{LHC}) are meant for the measurement of particles following very closely the beam path. Such devices, also used at \textsc{HERA} and Tevatron, are located very far away from the interaction point (further than $150$~m in the \textsc{LHC} case).
+To be able to reach these detectors, particles must have a charge identical to the beam particles, and a momentum very close to the nominal value of 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}).
+For instance, roman pots at $220~\textrm{m}$ from the  \textsc{IP} and $2~\textrm{mm}$ from the beam will detect all forward protons with an energy between $120$ and $900~\textrm{GeV}$~\citep{bib:hector}.
+In practice, in the \textsc{LHC}, only positively charged muons ($\mu^+$) and protons can reach the forward taggers as other particles with a single positive charge coming from the interaction points will decay before their possible tagging. In \textit{Delphes}, extra hits coming from the beam-gas events or secondary particles hitting the beampipe in front of the detectors are not taken into account.
+While neutral particles propagate along a straight line to the \textsc{ZDC}, a dedicated simulation of the transport of charged particles is needed for \textsc{RP220} and \textsc{FP420}. This fast simulation uses the \textit{Hector} software~\citep{bib:hector}, which includes the chromaticity effects and the geometrical aperture of the beamline elements of any arbitrary collider.
+Forward taggers are able to measure the hit positions ($x,y$) and angles ($\theta_x,\theta_y$) in the transverse plane at the location of the detector ($s$ meters away from the \textsc{IP}), as well as the time-of-flight\footnote{It should be noted that for both \textsc{CMS} and \textsc{ATLAS} experiments, the taggers located at $220$~m are not able to measure the time-of-flight, contrary to \textsc{FP420} detectors.} ($t$). Out of these the particle energy ($E$) and the momentum transfer it underwent during the interaction ($q^2$) can be reconstructed\footnote{The reconstruction of $E$ and $q^2$ are not implemeted in \textit{Delphes} but can be performed at the analysis level.}. The time-of-flight measurement can be smeared with a Gaussian distribution (default value\footnote{\texttt{[code] } The resolution is defined by the \texttt{RP220\_T\_resolution} and \texttt{RP420\_T\_resolution} parameters in the detector card.} $\sigma_t = 0~\textrm{s}$).
+No sharing between neighbouring cells is implemented when particles enter a cell very close to its geometrical edge. Due to the finite segmentation, the smearing, as defined in Eq.~\ref{eq:caloresolution}, is applied directly on the accumulated electromagnetic and hadronic energies of each calorimetric cell. The calorimetric cells directly enter in the calculation of the missing transverse energy (\textsc{MET}), and as input for the jet reconstruction algorithms.
 …
 \section{High-level object reconstruction}
+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 \textit{Delphes}.
+In addition, some detector data are added: tracks, calorimetric towers and hits in \textsc{ZDC}, \textsc{RP220} and \textsc{FP420}.
+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.
+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 \textit{Delphes}~\citep{qr:analysistree}.
+In addition, some detector data are added: tracks, calorimetric cells and hits in the very forward detectors (\textsc{ZDC}, \textsc{RP220} and \textsc{FP420}, Sec.~\ref{sec:vfd}). 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.
 For most of these objects, their four-momentum and related quantities are directly accessible in \textit{Delphes} output ($E$, $\vec{p}$, $p_T$, $\eta$ and $\phi$). Additional properties are available for specific objects (like the charge and the isolation status for $e^\pm$ and $\mu^\pm$, the result of application of $b$-tag for jets and time-of-flight for some detector hits).
 \subsection{Photon and charged lepton reconstruction}
 From here onwards, \textit{electrons} refer to both positrons ($e^+$) and electrons ($e^-$), and $\textit{charged leptons}$ refer to electrons and muons ($\mu^\pm$), leaving out the $\tau^\pm$ leptons as they decay before being detected.
+From here onwards, \textit{electrons} refer to both positrons ($e^+$) and electrons ($e^-$), and $\textit{charged leptons}$ refer to electrons and muons ($\mu^\pm$), leaving out the $\tau^\pm$ leptons as they decay before being detected. The collections of electrons, photons and muons are filled in with candidates observing some fiducial and reconstruction cuts, and are based on the true particle ID provided by the generator. Consequently, no fake candidates enter these collections. However, when needed, fake candidates can be added into the collections at the analysis level, when processing \textit{Delphes} output data. As effects like bremsstrahlung are not taken into account along the lepton propagation in the tracker, no clustering is needed for the electron reconstruction in \textit{Delphes}.
 \subsubsection*{Electrons and photons}
 Electron ($e^\pm$) and photon candidates are reconstructed if they fall into the acceptance of the tracking system and have a transverse momentum above a threshold (default $p_T > 10~\textrm{GeV}/c$). A calorimetric tower will be seen in the detector, as electrons will leave in addition a track. Subsequently, electrons and photons create a candidate in the jet collection.
 Assuming a good measurement of the track parameters in the real experiment, the electron energy can be reasonably recovered. In \textit{Delphes}, electron energy is smeared according to the resolution of the calorimetric tower where it points to, but independently from any other deposited energy is this tower. This approach is still conservative as the calorimeter resolution is worse than the tracker one.
+Real electron ($e^\pm$) and photon candidates are identified if they fall into the acceptance of the tracking system and have a transverse momentum above a threshold (default $p_T > 10~\textrm{GeV}/c$). A calorimetric cell will be activated in the detector and electrons will leave in addition a track. Subsequently, electrons and photons create a candidate in the jet collection.
+Assuming a good measurement of the track parameters in the real experiment, the electron energy can be reasonably recovered. In \textit{Delphes}, electron energy is smeared according to the resolution of the calorimetric cell where it points to, but independently from any other deposited energy is this cell. This approach is still conservative as the calorimeter resolution is worse than the tracker one.
 \subsubsection*{Muons}
 Generator-level muons entering the detector acceptance are considered as candidates for the analysis level.
 The acceptance is defined in terms of a transverse momentum threshold to be overpassed that should be computed using the chosen geometry of the detector and the magnetic field considered (default : $p_T > 10~\textrm{GeV}/c$) and of the pseudorapidity coverage of the muon system (default: $-2.4 \leq \eta \leq 2.4$).
+The application of the detector resolution on the muon momentum depends on a Gaussian smearing of the $p_T$ variable\footnote{\texttt{[code]} See the \texttt{SmearMuon} method.}. Neither $\eta$ nor $\phi$ variables are modified beyond the calorimeters: no additional magnetic field is applied. Multiple scattering is neglected. This implies that low energy muons have in \textit{Delphes} a better resolution than in a real detector. Furthermore, muons leave no deposit in calorimeters. At last, the particles which might leak out of the calorimeters into the muon systems (\textit{punch-through}) will not be see
+n as muon candidates in \textit{Delphes}.
+The application of the detector resolution on the muon momentum depends on a Gaussian smearing of the $p_T$ variable~\citep{qr:muonsmearing}.
+%\footnote{\texttt{[code]} See the \texttt{SmearMuon} method.}.
+Neither $\eta$ nor $\phi$ variables are modified beyond the calorimeters: no additional magnetic field is applied. Multiple scattering is neglected. This implies that low energy muons have in \textit{Delphes} a better resolution than in a real detector. Furthermore, muons leave no deposit in calorimeters. At last, the particles which might leak out of the calorimeters into the muon systems (\textit{punch-through}) will not be seen as muon candidates in \textit{Delphes}.
 \subsubsection*{Charged lepton isolation}
 …
 The result (i.e.\ \textit{isolated} or \textit{not}) is added to the charged lepton measured properties.
 In addition, the sum $P_T$ of the transverse momenta of all tracks but the lepton one within the isolation cone is
+provided\footnote{\texttt{[code] }See the \texttt{IsolFlag} and \texttt{IsolPt} values in the \texttt{Electron} or \texttt{Muon} collections in the \texttt{Analysis} tree, as well as the \texttt{ISOL\_PT} and \texttt{ISOL\_Cone} variables in the detector card.}:
+provided~\citep{qr:isolflag}:
+%\footnote{\texttt{[code] }See the \texttt{IsolFlag} and \texttt{IsolPt} values in the \texttt{Electron} or \texttt{Muon} collections in the \texttt{Analysis} tree, as well as the \texttt{ISOL\_PT} and \texttt{ISOL\_Cone} variables in the detector card.}
 $$ P_T = \sum_{i \neq \mu}^\textrm{tracks} p_T(i)$$
 No calorimetric isolation is applied, but the muon collection contains also the ratio $\rho_\mu$ between (1) the sum of the transverse energies in all calotowers in a $N \times N$ grid around the muon, and (2) the muon transverse
 momentum\footnote{\texttt{[code] }Calorimetric isolation parameters in the detector card are \texttt{ISOL\_Calo\_ET} and  \texttt{ISOL\_Calo\_Grid}.}:
+No calorimetric isolation is applied, but the muon collection contains also the ratio $\rho_\mu$ between (1) the sum of the transverse energies in all calorimetric cells in a $N \times N$ grid around the muon, and (2) the muon transverse momentum~\citep{qr:caloisolation}:
+%\footnote{\texttt{[code] }Calorimetric isolation parameters in the detector card are \texttt{ISOL\_Calo\_ET} and  \texttt{ISOL\_Calo\_Grid}.}:
 $$ \rho_\mu = \frac{\Sigma_i E_T(i)}{p_T(\mu)}~,~ i\textrm{ in }N \times N \textrm { grid centred on }\mu.$$
+\subsubsection*{Forward neutrals}
+The zero degree calorimeter hits correspond to neutral particles with a lifetime long enough to reach these detectors (default: $c \tau \geq 140~\textrm{m}$) and very large pseudorapidities (default: $|\eta|>8.3$). In current versions of \textit{Delphes}, only photons and neutrons are considered. Photons are identified thanks to the electromagnetic section of the calorimeter, and if their energy overpasses a given threshold (def. $20$~GeV). Similarly, neutrons are reconstructed according to the resolution of the hadronic section, if their energy exceeds a threshold\footnote{\texttt{[code]} These thresholds are defined by the \texttt{ZDC\_gamma\_E} and \texttt{ZDC\_n\_E} variables in the detector card.} (def. $50$~GeV).
+% \subsubsection*{Forward neutrals}
+%
+% The zero degree calorimeter hits correspond to neutral particles with a lifetime long enough to reach these detectors (default: $c \tau \geq 140~\textrm{m}$) and very large pseudorapidities (default: $|\eta|>8.3$). In current versions of \textit{Delphes}, only photons and neutrons are considered. Photons are identified thanks to the electromagnetic section of the calorimeter, and if their energy overpasses a given threshold (def. $20$~GeV). Similarly, neutrons are reconstructed according to the resolution of the hadronic section, if their energy exceeds a threshold (def. $50$~GeV)~\citep{qr:fwdneutrals}.
+% %\footnote{\texttt{[code]} These thresholds are defined by the \texttt{ZDC\_gamma\_E} and \texttt{ZDC\_n\_E} variables in the detector card.} (def. $50$~GeV).
 …
 \subsection{Jet reconstruction}
+A realistic analysis requires a correct treatment of particles which have hadronised. Therefore, the most widely currently used jet algorithms have been integrated into the \textit{Delphes} framework using the FastJet tools~\citep{bib:FASTJET}.
+Six different jet reconstruction schemes are available\footnote{\texttt{[code] }The choice is done by allocating the \texttt{JET\_jetalgo } input parameter in the detector 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 for the jet clustering. Jet algorithms differ in their sensitivity to soft particles or collinear splittings, and in their computing speed performances.
+A realistic analysis requires a correct treatment of particles which have hadronised. Therefore, the most widely currently used jet algorithms have been integrated into the \textit{Delphes} framework using the FastJet tools\footnote{A more detailed description of the jet algorithms is given in the User Manual, in appendix.}.
+Six different jet reconstruction schemes are available, with three cone algorithms and three recombination algorithms~\citep{bib:FASTJET,qr:jetalgo}.
+%\footnote{\texttt{[code] }The choice is done by allocating the \texttt{JET\_jetalgo } input parameter in the detector 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 calorimetric cells are used as inputs for the jet clustering. Jet algorithms differ in their sensitivity to soft particles or collinear splittings, and in their computing speed performances.
 By default, reconstruction uses a cone algorithm with $\Delta R=0.7$.
+Jets are stored if their transverse energy is higher\footnote{\texttt{[code] PTCUT\_jet }variable in the detector card.} than $20~\textrm{GeV}$.
+Jets are stored if their transverse energy is higher
+%\footnote{\texttt{[code] PTCUT\_jet }variable in the detector card.}
+than $20~\textrm{GeV}$~\citep{qr:ptcutjet}.
 \subsubsection*{Cone algorithms}
 …
 \begin{enumerate}
+\item {\it CDF Jet Clusters}~\citep{bib:jetclu}: Algorithm forming jets by associating together towers lying within a circle (default radius $\Delta R=0.7$) in the $(\eta$, $\phi)$ space.
+This so-called JetCLU cone jet algorithm is used by the \textsc{CDF} experiment in Run II.
+All towers with a transverse energy $E_T$ higher than a given threshold (default: $E_T > 1~\textrm{GeV}$) are used to seed the jet candidates.
+The existing FastJet code has been modified to allow easy modification of the tower pattern in $(\eta, \phi)$ space.
+In following versions of \textit{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 detector card.}.
+\item {\it CDF MidPoint}~\citep{bib:midpoint}: Algorithm developed for the \textsc{CDF} Run II to reduce infrared and collinear sensitivities compared to purely seed-based cone by adding `midpoints' (energy barycentres) in the list of cone seeds.
+\item {\it CDF Jet Clusters}~\citep{bib:jetclu}: Cone algorithm forming jets by combining cells lying within a circle (default radius $\Delta R=0.7$) in the $(\eta$, $\phi)$ space. Jets are seeded by all cells with
+ transverse energy $E_T$ overpassing a given threshold (default: $E_T > 1~\textrm{GeV}$)~\citep{qr:jetparams}.
+\item {\it CDF MidPoint}~\citep{bib:midpoint}: Cone algorithm with additional ``midpoints'' (energy barycentres) in the list of seeds; this algorithm has reduced infrared and collinear sensitivities.
 \item {\it Seedless Infrared Safe Cone}~\citep{bib:SIScone}: The \textsc{SISC}one algorithm is simultaneously insensitive to additional soft particles and collinear splittings, and fast enough to be used in experimental analysis.
 \end{enumerate}
 \subsubsection*{Recombination algorithms}
+The three sequential recombination jet algorithms are safe with respect to soft radiations (\textit{infrared}) and collinear splittings. They rely on recombination schemes where calorimeter tower pairs are successively merged. The definitions of the jet algorithms are similar except for the definition of the \textit{distances} $d$ used during the merging procedure. Two such variables are defined: the distance $d_{ij}$ between each pair of towers $(i,j)$, and a variable $d_{iB}$ (\textit{beam distance}) depending on the transverse momentum of the tower $i$.
+The jet reconstruction algorithm browses the calotower list. It starts by finding the minimum value $d_\textrm{min}$ of all the distances $d_{ij}$ and $d_{iB}$. If $d_\textrm{min}$ is a $d_{ij}$, the towers $i$ and $j$ are merged into a single tower with a four-momentum $p^\mu = p^\mu (i) + p^\mu (j)$ (\textit{E-scheme recombination}). If $d_\textrm{min}$ is a $d_{iB}$, the tower is declared as a final jet and is removed from the input list. This procedure is repeated until no towers are left in the input list. Further information on these jet algorithms is given here below, using $k_{ti}$, $y_{i}$ and $\phi_i$ as the transverse momentum, rapidity and azimuth of calotower $i$ and $\Delta R_{ij}= \sqrt{(y_i-y_j)^2+(\phi_i-\phi_j)^2}$ as the jet-radius parameter:
+The next three jet algorithms rely on recombination schemes where calorimeter cell pairs are successively merged (\textit{E-scheme recombination}):
+% Two such variables are defined: the distance $d_{ij}$ between each pair of cells $(i,j)$, and a variable $d_{iB}$ (\textit{beam distance}) depending on the transverse momentum of the cell $i$.
+% The jet reconstruction algorithm browses the calorimetric cell list. It starts by finding the minimum value $d_\textrm{min}$ of all the distances $d_{ij}$ and $d_{iB}$. If $d_\textrm{min}$ is a $d_{ij}$, the cells $i$ and $j$ are merged into a single cell with a four-momentum $p^\mu = p^\mu (i) + p^\mu (j)$ (\textit{E-scheme recombination}). If $d_\textrm{min}$ is a $d_{iB}$, the cell is declared as a final jet and is removed from the input list. This procedure is repeated until no cells are left in the input list. Further information on these jet algorithms is given here below, using $k_{ti}$, $y_{i}$ and $\phi_i$ as the transverse momentum, rapidity and azimuth of calorimetric cell $i$ and $\Delta R_{ij}= \sqrt{(y_i-y_j)^2+(\phi_i-\phi_j)^2}$ as the jet-radius parameter:
 \begin{enumerate}[start=4]
 \item {\it Longitudinally invariant $k_t$ jet}~\citep{bib:ktjet}:
 \begin{equation}
 \begin{array}{l}
   d_{ij} = \min(k_{ti}^2,k_{tj}^2)\Delta R_{ij}^2/R^2 \\
   d_{iB}=k_{ti}^2 \\
 \end{array}
 \end{equation}
 \item {\it Cambridge/Aachen jet}~\citep{bib:aachen}:
 \begin{equation}
 \begin{array}{l}
 d_{ij} = \Delta R_{ij}^2/R^2\\
 d_{iB}=1 \\
 \end{array}
 \end{equation}
 \item {\it Anti $k_t$ jet}~\citep{bib:antikt}: where hard jets are exactly circular in the $(y,\phi)$ plane
 \begin{equation}
 \begin{array}{l}
 d_{ij} =  \min(1/k_{ti}^2,1/k_{tj}^2)\Delta R_{ij}^2/R^2 \\
 d_{iB}=1/k_{ti}^2 \\
 \end{array}
 \end{equation}
+\item {\it Longitudinally invariant $k_t$ jet}~\citep{bib:ktjet},
+% \begin{equation}
+% \begin{array}{l}
+%   d_{ij} = \min(k_{ti}^2,k_{tj}^2)\Delta R_{ij}^2/R^2 \\
+%   d_{iB}=k_{ti}^2 \\
+% \end{array}
+% \end{equation}
+\item {\it Cambridge/Aachen jet}~\citep{bib:aachen},
+% \begin{equation}
+% \begin{array}{l}
+% d_{ij} = \Delta R_{ij}^2/R^2\\
+% d_{iB}=1 \\
+% \end{array}
+% \end{equation}
+\item {\it Anti $k_t$ jet}~\citep{bib:antikt}, where hard jets are exactly circular in the $(y,\phi)$ plane.
+% \begin{equation}
+% \begin{array}{l}
+% d_{ij} =  \min(1/k_{ti}^2,1/k_{tj}^2)\Delta R_{ij}^2/R^2 \\
+% d_{iB}=1/k_{ti}^2 \\
+% \end{array}
+% \end{equation}
 \end{enumerate}
+The recombination algorithms are safe with respect to soft radiations (\textit{infrared}) and collinear splittings. Their implementations are similar except for the definition of the \textit{distances} used during the merging procedure.
 \subsubsection*{Energy flow}
+In jets, several particle can leave their energy into a given calorimetric tower, which broadens the jet energy resolution. However, the energy of charged particles associated to jets can be deduced from their reconstructed track, thus providing a way to identify some of the components of towers with multiple hits. When the \textit{energy flow} is switched on in \textit{Delphes}\footnote{\texttt{[code]} Set \texttt{JET\_Eflow} to $1$ or $0$ in the detector card in order to switch on or off the energy flow for jet reconstruction.}, the energy of tracks pointing to calotowers is extracted and smeared separately, before running the chosen jet reconstruction algorithm. This option allows a better jet $E$ reconstruction.
+In jets, several particle can leave their energy into a given calorimetric cell, which broadens the jet energy resolution. However, the energy of charged particles associated to jets can be deduced from their reconstructed track, thus providing a way to identify some of the components of cells with multiple hits. When the \textit{energy flow} is switched on in \textit{Delphes}
+%\footnote{\texttt{[code]} Set \texttt{JET\_Eflow} to $1$ or $0$ in the detector card in order to switch on or off the energy flow for jet reconstruction.}
+, the energy of tracks pointing to calorimetric cells is extracted and smeared separately, before running the chosen jet reconstruction algorithm. This option allows a better jet $E$ reconstruction~\citep{qr:energyflow}.
 \subsection{$b$-tagging}
 \label{btagging}
+A jet is tagged as $b$-jets if its direction lies in the acceptance of the tracker and if it is associated to a parent $b$-quark. By default, a $b$-tagging efficiency of $40\%$ is assumed if the jet has a parent $b$ quark. For $c$-jets and light jets (i.e.\ originating in $u$, $d$, $s$ quarks or in gluons), a fake $b$-tagging efficiency of $10 \%$ and $1 \%$ respectively is assumed\footnote{\texttt{[code] }Corresponding to the \texttt{BTAG\_b}, \texttt{BTAG\_mistag\_c} and \texttt{BTAG\_mistag\_l} constants, for (respectively) the efficiency of tagging of a $b$-jet, the efficiency of mistagging a $c$-jet as a $b$-jet, and the efficiency of mistagging a light jet ($u$,$d$,$s$,$g$) as a $b$-jet.}.
+A jet is tagged as $b$-jets if its direction lies in the acceptance of the tracker and if it is associated to a parent $b$-quark. By default, a $b$-tagging efficiency of $40\%$ is assumed if the jet has a parent $b$ quark. For $c$-jets and light jets (i.e.\ originating in $u$, $d$, $s$ quarks or in gluons), a fake $b$-tagging efficiency of $10 \%$ and $1 \%$ respectively is assumed~\citep{qr:btag}.
+%\footnote{\texttt{[code] }Corresponding to the \texttt{BTAG\_b}, \texttt{BTAG\_mistag\_c} and \texttt{BTAG\_mistag\_l} constants, for (respectively) the efficiency of tagging of a $b$-jet, the efficiency of mistagging a $c$-jet as a $b$-jet, and the efficiency of mistagging a light jet ($u$,$d$,$s$,$g$) as a $b$-jet.}.
 The (mis)tagging relies on the true particle identity (\textsc{PID}) of the most energetic particle within a cone around the observed $(\eta,\phi)$ region, with a radius equal to the one used to reconstruct the jet (default: $\Delta R$ of $0.7$). In current version of \textit{Delphes}, the displacement of secondary vertices is not simulated.
 …
 \caption{ Branching ratios for $\tau^-$ lepton~\citep{bib:pdg}. $h^\pm$ and $h^0$ refer to charged and neutral hadrons, respectively. $n \geq 0$ and $m \geq 0$ are integers.
 \vspace{0.5cm}  }
 \begin{tabular}[!h]{ll}
+\begin{tabular}[!h]{lll}
 \hline
  \multicolumn{2}{l}{\textbf{Leptonic decays}}\\
  $ \tau^- \rightarrow e^- \ \bar \nu_e \ \nu_\tau$ & $17.9\% $ \\
  $ \tau^- \rightarrow \mu^- \ \bar \nu_\mu  \ \nu_\tau$ & $17.4\%$ \\
  \multicolumn{2}{l}{\textbf{Hadronic decays}}\\
  $ \tau^- \rightarrow h^-\ (n\times h^\pm) \ (m\times h^0) \  \nu_\tau$  & $64.7\%$ \\
  $ \tau^- \rightarrow h^-\ (m\times h^0) \ \nu_\tau$  & $50.1\%$ \\
  $ \tau^- \rightarrow h^-\ h^+ h^-  (m\times h^0) \ \nu_\tau$  & $14.6\%$ \\
+ \multicolumn{3}{l}{\textbf{Leptonic decays}}\\
+ & $ \tau^- \rightarrow e^- \ \bar \nu_e \ \nu_\tau$ & $17.9\% $ \\
+ & $ \tau^- \rightarrow \mu^- \ \bar \nu_\mu  \ \nu_\tau$ & $17.4\%$ \\
+ \multicolumn{3}{l}{\textbf{Hadronic decays}}\\
+ & $ \tau^- \rightarrow h^-\ (n\times h^\pm) \ (m\times h^0) \  \nu_\tau$  & $64.7\%$ \\
+ & $ \tau^- \rightarrow h^-\ (m\times h^0) \ \nu_\tau$  & $50.1\%$ \\
+ & $ \tau^- \rightarrow h^-\ h^+ h^-  (m\times h^0) \ \nu_\tau$  & $14.6\%$ \\
 \hline
 \end{tabular}
 …
 \begin{table}[!h]
 \begin{center}
 \caption{Default values for parameters used in $\tau$-jet reconstruction algorithm. Electromagnetic collimation requirements involve the inner \textit{small} cone radius $R^\textrm{em}$, the minimum transverse energy for calotowers $E_T^\textrm{tower}$ and the collimation factor $C_\tau$. Tracking isolation constrains the number of tracks with a significant transverse momentum $p_T^\textrm{tracks}$ in a cone of radius $R^\textrm{tracks}$.  Finally, the $\tau$-jet collection is purified by the application of a cut on the $p_T$ of $\tau$-jet candidates.
+\caption{Default values for parameters used in $\tau$-jet reconstruction algorithm. Electromagnetic collimation requirements involve the inner \textit{small} cone radius $R^\textrm{em}$, the minimum transverse energy for calorimetric cells $E_T^\textrm{tower}$ and the collimation factor $C_\tau$. Tracking isolation constrains the number of tracks with a significant transverse momentum $p_T^\textrm{tracks}$ in a cone of radius $R^\textrm{tracks}$.  Finally, the $\tau$-jet collection is purified by the application of a cut on the $p_T$ of $\tau$-jet candidates~\citep{qr:taujets}.
 \vspace{0.5cm}  }
+% \begin{tabular}[!h]{lll}
+% \hline
+% Parameter  & Card flag & Value\\\hline
+% \multicolumn{3}{l}{\textbf{Electromagnetic collimation}} \\
+% $R^\textrm{em}$     & \texttt{TAU\_energy\_scone } & $0.15$\\
+% min $E_{T}^\textrm{tower}$     & {\verb JET_M_seed }  & $1.0$~GeV\\
+% $C_{\tau}$         & \texttt{TAU\_energy\_frac} & $0.95$\\
+% \multicolumn{3}{l}{\textbf{Tracking isolation}} \\
+% $R^\textrm{tracks}$ & \texttt{TAU\_track\_scone} & $0.4$\\
+% min $p_T^\textrm{tracks}$      & \texttt{PTAU\_track\_pt } & $2$ GeV$/c$\\
+% \multicolumn{3}{l}{\textbf{$\tau$-jet candidate}} \\
+% $\min p_T$ & \texttt{TAUJET\_pt} & $10$ GeV$/c$\\
+% \hline
+% \end{tabular}
 \begin{tabular}[!h]{lll}
 \hline
-Parameter  & Card flag & Value\\\hline
 \multicolumn{3}{l}{\textbf{Electromagnetic collimation}} \\
 $R^\textrm{em}$     & \texttt{TAU\_energy\_scone } & $0.15$\\
 min $E_{T}^\textrm{tower}$     & {\verb JET_M_seed }  & $1.0$~GeV\\
 $C_{\tau}$         & \texttt{TAU\_energy\_frac} & $0.95$\\
+& $R^\textrm{em}$          & $0.15$\\
+& min $E_{T}^\textrm{tower}$ & $1.0$~GeV\\
+& $C_{\tau}$               & $0.95$\\
 \multicolumn{3}{l}{\textbf{Tracking isolation}} \\
 $R^\textrm{tracks}$ & \texttt{TAU\_track\_scone} & $0.4$\\
 min $p_T^\textrm{tracks}$      & \texttt{PTAU\_track\_pt } & $2$ GeV$/c$\\
+& $R^\textrm{tracks}$      & $0.4$\\
+& min $p_T^\textrm{tracks}$  & $2$ GeV$/c$\\
 \multicolumn{3}{l}{\textbf{$\tau$-jet candidate}} \\
 $\min p_T$ & \texttt{TAUJET\_pt} & $10$ GeV$/c$\\
+& $\min p_T$               & $10$ GeV$/c$\\
 \hline
 \end{tabular}
 …
 \subsubsection*{Electromagnetic collimation}
 To use the narrowness of the $\tau$-jet, the \textit{electromagnetic collimation} $C_{\tau}$ is defined as the sum of the energy of towers in a small cone of radius $R^\textrm{em}$ around the jet axis, divided by the energy of the reconstructed jet.
 To be taken into account, a calorimeter tower should have a transverse energy $E_T^\textrm{tower}$ above a given threshold.
+To use the narrowness of the $\tau$-jet, the \textit{electromagnetic collimation} $C_{\tau}$ is defined as the sum of the energy of cells in a small cone of radius $R^\textrm{em}$ around the jet axis, divided by the energy of the reconstructed jet.
+To be taken into account, a calorimeter cell should have a transverse energy $E_T^\textrm{tower}$ above a given threshold.
 A large fraction of the jet energy is expected in this small cone. This fraction, or \textit{collimation factor}, is represented in Fig.~\ref{fig:tau2} for the default values (see Tab.~\ref{tab:tauRef}).
 …
 \end{equation}
 The \textit{true} missing transverse energy, i.e.\ at generator-level, is calculated as the opposite of the vector sum of the transverse momenta of all visible particles -- or equivalently, to the vector sum of invisible particle transverse momenta.
 In a real experiment, calorimeters measure energy and not momentum. Any problem affecting the detector (dead channels, misalignment, noisy towers, cracks) worsens directly the measured missing transverse energy $\overrightarrow {E_T}^\textrm{miss}$. In this document, \textsc{MET} is based on the calorimetric towers and only muons and neutrinos are not taken into account for its evaluation\footnote{However, as tracks and calorimetric towers are available in the output file, the missing transverse energy can always be reprocessed a posteriori. }:
+In a real experiment, calorimeters measure energy and not momentum. Any problem affecting the detector (dead channels, misalignment, noisy cells, cracks) worsens directly the measured missing transverse energy $\overrightarrow {E_T}^\textrm{miss}$. In this document, \textsc{MET} is based on the calorimetric cells and only muons and neutrinos are not taken into account for its evaluation:
 \begin{equation}
 \overrightarrow{E_T}^\textrm{miss} = - \sum^\textrm{towers}_i \overrightarrow{E_T}(i)
 \end{equation}
+However, as muon candidates, tracks and calorimetric cells are available in the output file, the missing transverse energy can always be reprocessed a posteriori with more specialised algorithms.
 \section{Trigger emulation}
 …
 %High statistics are required for data analyses, consequently imposing high luminosity, i.e.\ a high collision rate.
 As only a tiny fraction of the observed events can be stored for subsequent \textit{offline} analyses, a very large data rejection factor should be applied directly as the events are produced.
 This data selection is supposed to reject only well-known \textsc{SM} events\footnote{However, some bandwidth is allocated to minimum-bias and/or zero-bias (``random'') triggers that stores a small fraction of the events without any selection criteria.}.
+This data selection is supposed to reject only well-known \textsc{SM} events\footnote{In real experiments, some bandwidth is allocated to minimum-bias and/or zero-bias (``random'') triggers that stores a small fraction of  random events without any selection criteria.}.
 Dedicated algorithms of this \textit{online} selection, or \textit{trigger}, should be fast and very efficient for data rejection, in order to preserve the experiment output bandwidth. They must also be as inclusive as possible to avoid loosing interesting events.
 Most of the usual trigger algorithms select events containing objects (i.e.\ jets, particles, \textsc{MET}) with an energy scale above some threshold. This is often expressed in terms of a cut on the transverse momentum of one or several objects of the measured event. Logical combinations of several conditions are also possible. For instance, a trigger path could select events containing at least one jet and one electron such as $p_T^\textrm{jet} > 100~\textrm{GeV}/c$ and $p_T^e > 50~\textrm{GeV}/c$.
+A trigger emulation is included in \textit{Delphes}, using a fully parametrisable \textit{trigger table}\footnote{\texttt{[code] }The trigger card is the \texttt{data/TriggerCard.dat} file.}. When enabled, this trigger is applied on analysis-object data.
+A trigger emulation is included in \textit{Delphes}, using a fully parametrisable \textit{trigger table} \citep{qr:triggercard}
+%\footnote{\texttt{[code] }The trigger card is the \texttt{data/TriggerCard.dat} file.}
+. When enabled, this trigger is applied on analysis-object data.
 In a real experiment, the online selection is often divided into several steps (or \textit{levels}).
 This splits the overall reduction factor into a product of smaller factors, corresponding to the different trigger levels.
 …
 Real triggers are thus intrinsically based on reconstructed data with a worse resolution than final analysis data.
 On the contrary, same data are used in \textit{Delphes} for trigger emulation and for final analyses.
+\section{\label{sec:vfd}Very forward detector simulation}
+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. In \textit{Delphes}, Zero Degree Calorimeters, roman pots and forward taggers have been implemented (Fig.~\ref{fig:fdets}), similarly to the plans for CMS and ATLAS collaborations~\citep{bib:cmsjetresolution, bib:ATLASresolution}.
+\begin{figure}[!ht]
+\begin{center}
+%\includegraphics[width=\columnwidth]{fdets}
+\includegraphics[width=\columnwidth]{fig4}
+\caption{Default location of the very forward detectors, including \textsc{ZDC}, \textsc{RP220} and \textsc{FP420} in the \textsc{LHC} beamline.
+Incoming (beam 1, red) and outgoing (beam 2, black) beams on one side of the fifth interaction point (\textsc{IP5}, $s=0~\textrm{m}$ on the plot).
+The Zero Degree Calorimeter is located in perfect alignment with the beamline axis at the interaction point, at $140~\textrm{m}$, the beam paths are separated. The forward taggers are near-beam detectors located at $220~\textrm{m}$ and $420~\textrm{m}$. Beamline simulation with \textit{Hector}~\citep{bib:hector}. All very forward detectors are located symmetrically around the interaction point. }
+\label{fig:fdets}
+\end{center}
+\end{figure}
+%\begin{table*}[t]  % the star (*) allows to arrange the table over the two columns
+\begin{table}[t]
+\begin{center}
+\caption{Default parameters for the forward detectors: distance from the interaction point and detector acceptance. The \textsc{LHC} beamline is assumed around the fifth \textsc{LHC} interaction point (\textsc{IP}). For the \textsc{ZDC}, the acceptance depends only on the pseudorapidity $\eta$ of the particle, which should be neutral and stable.
+The tagger acceptance is fully determined by the distance in the transverse plane of the detector to the real beam position~\citep{bib:hector}. It is expressed in terms of the particle energy ($E$).
+All detectors are located on both sides of the interaction point.
+\vspace{0.5cm}}
+\begin{tabular}{llcl}
+\hline
+%Detector & Distance from \textsc{IP}& Acceptance & \\ \hline
+Detector & Distance & Acceptance & \\ \hline
+\textsc{ZDC}   & $\pm 140$ m & $|\eta|> 8.3$       & for $n$ and $\gamma$\\
+\textsc{RP220} & $\pm 220$ m & $E \in [6100 ; 6880]$ (GeV) & at $2~\textrm{mm}$\\
+\textsc{FP420} & $\pm 420$ m & $E \in [6880 ; 6980]$ (GeV) & at $4~\textrm{mm}$\\
+\hline
+\end{tabular}
+\label{tab:fdetacceptance}
+\end{center}
+\end{table}
+\subsection{Zero Degree Calorimeters}
+In direct sight of the interaction point, on both sides of the central detector, the Zero Degree Calorimeters (\textsc{ZDC}s) are located at zero angle, i.e.\ are aligned with the beamline axis at the interaction point. They are placed beyond the point where the paths of incoming and outgoing beams separate. 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{ATLAS} and \textsc{CMS}).
+The trajectory of the neutrals observed in the \textsc{ZDC}s is a straight line, while charged particles are deflected away from their acceptance window by the powerful magnets located in front of them. The fact that additional charged particles may enter the \textsc{ZDC} acceptance is neglected in the current versions of \textit{Delphes}.
+The \textsc{ZDC}s have the ability to measure the time-of-flight of the particle.
+This corresponds to the delay $t$ after which the particle is observed in the detector, with respect to the bunch crossing reference time at the interaction point ($t_0$):
+\begin{equation}
+ t = t_0 + \frac{1}{v} \times \Big( \frac{s-z}{\cos \theta}\Big) \approx \frac{1}{c} \times (s-z),
+\end{equation}
+where $t_0$ is thus the true time coordinate of the vertex from which the particle originates, $v$ the particle velocity, $s$ is the \textsc{ZDC} distance to the interaction point, $z$ is the longitudinal coordinate of the vertex, $\theta$ is the particle emission angle. It is assumed that the neutral particle observed in the \textsc{ZDC} is highly relativistic and very forward.
+% that $\cos \theta = 1$, i.e.\ $\theta \approx 0$ or equivalently $\eta$ is large. As an example, $\eta = 5$ leads to $\theta = 0.013$ and $1 - \cos \theta < 10^{-4}$.
+% The formula then reduces to
+% \begin{equation}
+%  t = \frac{1}{c} \times (s-z).
+% \end{equation}
+% For example, a photon takes $0.47~\mu\textrm{s}$ to reach a \textsc{ZDC} located at $s=140~\textrm{m}$, neglecting $z$ and $\theta$.
+For the time-of-flight measurement, a Gaussian smearing can be applied according to the detector resolution (Tab.~\ref{tab:defResolZdc})~\citep{qr:resolutionterms}.
+%In the current version of \textit{Delphes}, only neutrons, antineutrons and photons are assumed to be able to reach the \textsc{ZDC}s, all other particles being neglected.
+The \textsc{ZDC}s are composed of an electromagnetic and a hadronic sections, for the measurement of photons and neutrons, respectively. The energy of the observed neutral is smeared according to Eq.~\ref{eq:caloresolution} and the corresponding section resolutions (Tab.~\ref{tab:defResolZdc}). The \textsc{ZDC} hits do not enter in the calorimeter cell list used for reconstruction of jets and missing transverse energy.
+\begin{table}[!h]
+\begin{center}
+\caption{Default values for the resolution of the zero degree calorimeters. Resolution on energy measurement is parametrised by the \textit{stochastic} ($S$), \textit{noise} ($N$) and \textit{constant} ($C$) terms (Eq.~\ref{eq:caloresolution})~\citep{qr:resolutionterms}. The time-of-flight is smeared according to a Gaussian function.
+\vspace{0.5cm}}
+% \begin{tabular}[!h]{lllc}
+% \hline
+% \multicolumn{2}{c}{Resolution Term}   & Card flag & Value\\\hline
+%  \multicolumn{4}{l}{\textsc{ZDC}, electromagnetic part} \\
+%         & $S$ (GeV$^{1/2}$)& \texttt{ELG\_Szdc}  & $0.7$ \\
+%         & $N$ (GeV)& \texttt{ELG\_Nzdc}  & $0.0$ \\
+%         & $C$ & \texttt{ELG\_Czdc}  & $0.08$ \\
+%  \multicolumn{4}{l}{\textsc{ZDC}, hadronic part} \\
+%         & $S$ (GeV$^{1/2}$)& \texttt{HAD\_Szdc}   & $1.38$\\
+%         & $N$ (GeV)& \texttt{HAD\_Nzdc}   & $0$ \\
+%         & $C$ & \texttt{HAD\_Czdc}   & $0.13$\\
+%  \multicolumn{4}{l}{\textsc{ZDC}, timing resolution} \\
+%         & $\sigma_t$ (s) & \texttt{ZDC\_T\_resolution} & $0$ \\
+% \hline
+% \end{tabular}
+\begin{tabular}[!h]{llcc}
+\hline
+ \multicolumn{3}{l}{\textsc{ZDC}, electromagnetic part} & hadronic part \\
+        & $S$ (GeV$^{1/2}$)     & $0.7$ & $1.38$\\
+        & $N$ (GeV)             & $0$   & $0$   \\
+        & $C$                   & $0.08$& $0.13$ \\
+  \multicolumn{4}{l}{\textsc{ZDC}, timing resolution} \\
+        & $\sigma_t$ (s) & $0$ & \\
+\hline
+\end{tabular}
+\label{tab:defResolZdc}
+\end{center}
+\end{table}
+% \subsubsection*{Forward neutrals}
+The reconstructed ZDC hits correspond to neutral particles with a lifetime long enough to reach these detectors (default: $c \tau \geq 140~\textrm{m}$) and very large pseudorapidities (default: $|\eta|>8.3$).
+%In current versions of \textit{Delphes}, only photons and neutrons are considered.
+Photons are identified thanks to the electromagnetic section of the calorimeter, and if their energy overpasses a given threshold (def. $20$~GeV). Similarly, neutrons are reconstructed according to the resolution of the hadronic section, if their energy exceeds a threshold (def. $50$~GeV)~\citep{qr:fwdneutrals}.
+%\footnote{\texttt{[code]} These thresholds are defined by the \texttt{ZDC\_gamma\_E} and \texttt{ZDC\_n\_E} variables in the detector card.} (def. $50$~GeV).
+\subsection{Forward taggers}
+Forward taggers (called here \textsc{RP220}, for ``roman pots at $220~\textrm{m}$'' and \textsc{FP420} for ``forward proton taggers at $420~\textrm{m}$'', as at the \textsc{LHC}) are meant for the measurement of particles following very closely the beam path. Such devices, also used at \textsc{HERA} and Tevatron, are located very far away from the interaction point (further than $150$~m in the \textsc{LHC} case).
+To be able to reach these detectors, particles must have a charge identical to the beam particles, and a momentum very close to the nominal value of 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}).
+For instance, roman pots at $220~\textrm{m}$ from the  \textsc{IP} and $2~\textrm{mm}$ from the beam will detect all forward protons with an energy between $120$ and $900~\textrm{GeV}$~\citep{bib:hector}.
+In practice, in the \textsc{LHC}, only positively charged muons ($\mu^+$) and protons can reach the forward taggers as other particles with a single positive charge coming from the interaction points will decay before their possible tagging. In \textit{Delphes}, extra hits coming from the beam-gas events or secondary particles hitting the beampipe in front of the detectors are not taken into account.
+While neutral particles propagate along a straight line to the \textsc{ZDC}, a dedicated simulation of the transport of charged particles is needed for \textsc{RP220} and \textsc{FP420}. This fast simulation uses the \textit{Hector} software~\citep{bib:hector}, which includes the chromaticity effects and the geometrical aperture of the beamline elements of any arbitrary collider.
+Forward taggers are able to measure the hit positions ($x,y$) and angles ($\theta_x,\theta_y$) in the transverse plane at the location of the detector ($s$ meters away from the \textsc{IP}), as well as the time-of-flight\footnote{It is worth noting that for both \textsc{CMS} and \textsc{ATLAS} experiments, the taggers located at $220$~m are not able to measure the time-of-flight, contrary to \textsc{FP420} detectors.} ($t$). Out of these the particle energy ($E$) and the momentum transfer it underwent during the interaction ($q^2$) can be reconstructed at the analysis level (it is not implemented in the current versions of \textit{Delphes}. The time-of-flight measurement can be smeared with a Gaussian distribution (default value
+%\footnote{\texttt{[code] } The resolution is defined by the \texttt{RP220\_T\_resolution} and \texttt{RP420\_T\_resolution} parameters in the detector card.}
+$\sigma_t = 0~\textrm{s}$)~\citep{qr:protontaggers}.
 \section{Validation}
 …
 The samples used to study the \textsc{MET} performance are identical to those used for the jet validation.
 It is worth noting that the contribution to $E_T^\textrm{miss}$ from muons is negligible in the studied sample.
 The input samples are divided in five bins of scalar $E_T$ sums $(\Sigma E_T)$. This sum, called \textit{total visible transverse energy}, is defined as the scalar sum of transverse energy in all towers.
+The input samples are divided in five bins of scalar $E_T$ sums $(\Sigma E_T)$. This sum, called \textit{total visible transverse energy}, is defined as the scalar sum of transverse energy in all cells.
 The quality of the \textsc{MET} reconstruction is checked via the resolution on its horizontal component $E_x^\textrm{miss}$.
 …
 \includegraphics[width=\columnwidth]{fig10}
 \includegraphics[width=\columnwidth]{fig10b}
 \caption{$\sigma(E^\textrm{mis}_{x})$ as a function on the scalar sum of all towers ($\Sigma E_T$) for $pp \rightarrow gg$ events, for a \textsc{CMS}-like detector (top) and an \textsc{ATLAS}-like detector (bottom), for di-jet events produced with MadGraph/MadEvent and hadronised with \textit{Pythia}.}
+\caption{$\sigma(E^\textrm{mis}_{x})$ as a function on the scalar sum of all cells ($\Sigma E_T$) for $pp \rightarrow gg$ events, for a \textsc{CMS}-like detector (top) and an \textsc{ATLAS}-like detector (bottom), for di-jet events produced with MadGraph/MadEvent and hadronised with \textit{Pythia}.}
 \label{fig:resolETmis}
 \end{center}
 …
 where the $\alpha$ parameter depends on the resolution of the calorimeters.
 The \textsc{MET} resolution expected for the \textsc{CMS} detector for similar events is $\sigma_x = (0.6-0.7) ~ \sqrt{E_T} ~ \mathrm{GeV}^{1/2}$ with no pile-up\footnote{\textit{Pile-up} events are extra simultaneous $pp$ collision occurring at high-luminosity in the same bunch crossing.}~\citep{bib:cmsjetresolution}, which compares very well with the $\alpha = 0.63$ obtained with \textit{Delphes}. Similarly, for an \textsc{ATLAS}-like detector, a value of $0.53$ is obtained by \textit{Delphes} for the $\alpha$ parameter, while the experiment expects it in the range $[0.53~ ;~0.57]$~\citep{bib:ATLASresolution}.
+The \textsc{MET} resolution expected for the \textsc{CMS} detector for similar events is $\sigma_x = (0.6-0.7) ~ \sqrt{E_T} ~ \mathrm{GeV}^{1/2}$ with no pile-up (i.e. extra simultaneous $pp$ collision occurring at high-luminosity in the same bunch crossing)~\citep{bib:cmsjetresolution}, which compares very well with the $\alpha = 0.63$ obtained with \textit{Delphes}. Similarly, for an \textsc{ATLAS}-like detector, a value of $0.53$ is obtained by \textit{Delphes} for the $\alpha$ parameter, while the experiment expects it in the range $[0.53~ ;~0.57]$~\citep{bib:ATLASresolution}.
 \subsection{\texorpdfstring{$\tau$}{\texttau}-jet efficiency}
 …
 \section{Visualisation}
+When performing an event analysis, a visualisation tool is useful to convey information about the detector layout and the event topology in a simple way. The \textit{Fast and Realistic OpenGL Displayer} \textsc{FROG}~\citep{bib:FROG} has been interfaced in \textit{Delphes}, allowing an easy display of the defined detector configuration\footnote{\texttt{[code] } To prepare the visualisation, the \texttt{FLAG\_FROG} parameter should be equal to $1$.}.
+When performing an event analysis, a visualisation tool is useful to convey information about the detector layout and the event topology in a simple way. The \textit{Fast and Realistic OpenGL Displayer} \textsc{FROG}~\citep{bib:FROG} has been interfaced in \textit{Delphes}, allowing an easy display of the defined detector configuration~\citep{qr:frog}.
+%\footnote{\texttt{[code] } To prepare the visualisation, the \texttt{FLAG\_FROG} parameter should be equal to $1$.}.
 % \begin{figure}[!ht]
 …
 Moreover, the framework allows trigger emulation and 3D event visualisation.
+\textit{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.
+This framework has already been used for several analyses, in particular in photon-induced interactions at the \textsc{LHC}~\citep{bib:wtphotoproduction, bib:papierquisortirajamais, bib:papiersimon}.
+\textit{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, a better $b$-tag description and possibly the implementation of an event mixing module for pile-up event simulation. This framework has already been used for several analyses~\citep{bib:wtphotoproduction, bib:papierquisortirajamais, bib:papiersimon}, in particular in photon-induced interactions at the \textsc{LHC}.
 …
 \begin{thebibliography}{99}
 \addcontentsline{toc}{section}{References}
+\bibitem{bib:geant} J. Allison, et al., Nucl. Inst. \& Meth. in \textbf{Phys. Res. A} \href{http://dx.doi.org/10.1016/S0168-9002(03)01368-8}{506 (2003) 250-303}; \textbf{IEEE Trans. on Nucl. Sc.} \href{http://dx.doi.org/10.1109/TNS.2006.869826}{53:1 (2006) 270-278}.
 \bibitem{bib:delphes} \textit{Delphes}, \href{http://www.fynu.ucl.ac.be/delphes.html}{www.fynu.ucl.ac.be/delphes.html}
-%hepforge:
 \bibitem{bib:stdhep} L.A. Garren, M. Fischler, \href{http://cepa.fnal.gov/psm/stdhep/c++}{cepa.fnal.gov/psm/stdhep/c++}
 \bibitem{bib:hepmc} M. Dobbs and J.B. Hansen, \textbf{Comput. Phys. Commun.} \href{http://dx.doi.org/10.1016/S0010-4655(00)00189-2}{134 (2001) 41}.
 …
 \bibitem{bib:wtphotoproduction} J. de Favereau de Jeneret, S. Ovyn, \textbf{Nucl. Phys. Proc. Suppl.} \href{http://dx.doi.org/10.1016/j.nuclphysbps.2008.07.040}{179-180 (2008)} \href{http://dx.doi.org/10.1016/j.nuclphysbps.2008.07.040}{277-284}; S. Ovyn, J. de Favereau de Jeneret, \href{http://dx.doi.org/10.1393/ncb/i2008-10684-5}{Nuovo Cimento B}, arXiv:0806.4841[hep-ph].
 \bibitem{bib:papierquisortirajamais}J. de Favereau~et~al, \textbf{CP3-08-04} (2008), to be published in EPJ.
+\bibitem{bib:papierquisortirajamais}J. de Favereau~et~al, \href{http://arxiv.org/abs/0908.2020}{arXiv:0908.2020v1} [hep-ph] (2008), to be published in EPJ.
 %\bibitem{bib:papiersimon} ``Phenomenology of a twisted two-Higgs-doublet model'', Simon de Visscher, Jean-Marc Gerard, Michel Herquet, Vincent Lema\^itre, Fabio Maltoni, to be published.
 …
 \bibitem{bib:mcfio} P. Lebrun, L. Garren, Copyright (c) 1994-1995 Universities Research Association, Inc.
 \end{thebibliography}
+% references to code
+\renewcommand\refname{Internal code references}
+\begin{thebibliography}{2}
+\addcontentsline{toc}{section}{Internal code references}
+\bibitem[a]{qr:inputformat} See the following classes: \texttt{HEPEVTConverter}, \texttt{HepMCConverter}, \texttt{LHEFConverter}, \texttt{STDHEPConverter} and \texttt{DelphesRootConverter}.
+\bibitem[b]{qr:invisibleparticles} The list of particles considered as invisible is accessible in the \texttt{PdgParticle} class. This list currently contains the PIDs 12, 14, 16, 1000022,  1000023, 1000025, 1000035 and 1000045, in absolute values.
+\bibitem[c]{qr:lhco} Set the \texttt{FLAG\_LHCO} variable to $1$ or $0$ in the detector card to switch on/off the creation of \texttt{*.lhco} output file.
+\bibitem[d]{qr:detectorcard}The detector card is the \texttt{data/DetectorCard.dat} file. This file is parsed by the \texttt{SmearUtil} class.
+\bibitem[e]{qr:datacards} Detector and trigger cards for the \textsc{ATLAS} and \textsc{CMS} experiments are also provided in \texttt{data/} directory.
+\bibitem[f]{qr:resolutionterms}The resolution terms in the detector card are named \texttt{ELG\_Xyyy} or \texttt{HAD\_Xyyy},  refering to electromagnetic and hadronic terms (resp.); \texttt{X} is replaced by \texttt{S}, \texttt{N}, \texttt{C} for the stochastic, noise and constant terms; and finally \texttt{yyy} is \texttt{cen} for central part, \texttt{ec} for end-caps, \texttt{fwd} for the forward calorimeters and \texttt{zdc} for the zero-degree calorimeters.
+\bibitem[g]{qr:magneticfield} See the \texttt{TrackPropagation} class.
+\bibitem[h]{qr:tracks} See the \texttt{TRACK\_eff} and \texttt{TRACK\_ptmin} terms in the detector card.
+\bibitem[i]{qr:energysmearing} The response of the detector is applied to the electromagnetic and the hadronic particles through the \texttt{SmearElectron} and \texttt{SmearHadron} methods in the \texttt{SmearUtil} class.
+\bibitem[j]{qr:emhadratios} To implement different ratios for other particles, see the \texttt{BlockClasses} class.
+\bibitem[k]{qr:calorimetriccells} As the detector is assumed to be cylindrical (e.g.\ symmetric in $\phi$ and with respect to the $\eta=0$ plane), the detector card stores the number of calorimetric cells with $\phi=0$ and $\eta>0$ (default: $40$ cells). For a given $\eta$, the size of the $\phi$ segmentation is also specified. See the \texttt{TOWER\_number}, \texttt{TOWER\_eta\_edges} and \texttt{TOWER\_dphi} variables in the detector card.
+\bibitem[l]{qr:analysistree} All these processed data are located under the \texttt{Analysis} tree.
+\bibitem[m]{qr:muonsmearing} See the \texttt{SmearMuon} method in the \texttt{SmearUtil} class.
+\bibitem[n]{qr:isolflag} See the \texttt{IsolFlag} and \texttt{IsolPt} values in the \texttt{Electron} or \texttt{Muon} collections in the \texttt{Analysis} tree, as well as the \texttt{ISOL\_PT} and \texttt{ISOL\_Cone} variables in the detector card.
+\bibitem[o]{qr:caloisolation} Calorimetric isolation parameters in the detector card are \texttt{ISOL\_Calo\_ET} and  \texttt{ISOL\_Calo\_Grid} in the detector card.
+\bibitem[p]{qr:fwdneutrals} These thresholds are defined by the \texttt{ZDC\_gamma\_E} and \texttt{ZDC\_n\_E} variables in the detector card.
+\bibitem[q]{qr:jetalgo} The choice is done by allocating the \texttt{JET\_jetalgo } input parameter in the detector card.
+\bibitem[r]{qr:ptcutjet} See the \texttt{PTCUT\_jet }variable in the detector card.
+\bibitem[s]{qr:jetparams} See the \texttt{JET\_coneradius} and \texttt{JET\_seed} variables in the detector card. The existing FastJet code has been modified to allow easy modification of the cell pattern in $(\eta, \phi)$ space.
+In following versions of \textit{Delphes}, a new dedicated plug-in will be created on this purpose.
+\bibitem[t]{qr:energyflow} Set \texttt{JET\_Eflow} to $1$ or $0$ in the detector card in order to switch on or off the energy flow for jet reconstruction.
+\bibitem[u]{qr:btag} Corresponding to the \texttt{BTAG\_b}, \texttt{BTAG\_mistag\_c} and \texttt{BTAG\_mistag\_l} constants, for the efficiency of tagging of a $b$-jet, the efficiency of mistagging a $c$-jet as a $b$-jet, and the
+efficiency of mistagging a light jet ($u$,$d$,$s$,$g$) as a $b$-jet.
+\bibitem[v]{qr:taujets} See the following parameters in the detector card:\\
+\texttt{TAU\_energy\_scone } for $R^\textrm{em}$; \texttt{JET\_M\_seed }  for min $E_{T}^\textrm{tower}$;
+\texttt{TAU\_energy\_frac} for $C_{\tau}$; \texttt{TAU\_track\_scone} for $R^\textrm{tracks}$;
+ \texttt{PTAU\_track\_pt } for min $p_T^\textrm{tracks}$ and \texttt{TAUJET\_pt} for $\min p_T$.
+\bibitem[w]{qr:triggercard} The trigger card is the \texttt{data/TriggerCard.dat} file. Default trigger files are also available for CMS-like and ATLAS-like detectors
+\bibitem[x]{qr:protontaggers} The resolution is defined by the \texttt{RP220\_T\_resolution} and \texttt{RP420\_T\_resolution} parameters in the detector card.
+\bibitem[y]{qr:frog} To prepare the visualisation, the \texttt{FLAG\_FROG} parameter should be equal to $1$.
+\end{thebibliography}
 \onecolumn
 \appendix
 \section{User manual}
 …
 In order to run \textit{Delphes} on your system, first download its sources and compile them:\\
 \texttt{wget http://www.fynu.ucl.ac.be/users/s.ovyn/Delphes/files/Delphes\_V\_*.tar.gz}\\
 Replace the \texttt{*} symbol by the proper version number\footnote{Refer to the download page on the \textit{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}. Current version of Delphes for this manual is V 1.8 (July 2009)}.
+\begin{quote}\texttt{wget http://www.fynu.ucl.ac.be/users/s.ovyn/Delphes/files/Delphes\_V\_*.tar.gz}\end{quote}
+Replace the \texttt{*} symbol by the proper version number. Always refer to the download page on the \textit{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}. Current version of Delphes for this manual is V 1.8 (July 2009).
 \begin{quote}
 …
  \end{itemize}
 If no datacard is provided by the user, the default smearing and running parameters are used:
+\begin{quote}
 \begin{verbatim}
+# Detector extension, in pseudorapidity units (|eta|)
+If no datacard is provided by the user, the default smearing and running parameters are used (corresponding to tables~\ref{tab:defEta},~\ref{tab:defResol}).\\
+Definition of the sub-detector extensions:
+\begin{quote}
+\begin{verbatim}
 CEN_max_tracker    2.5     // Maximum tracker coverage
 CEN_max_calo_cen   1.7     // central calorimeter coverage
 …
 CEN_max_calo_fwd   5.0     // forward calorimeter pseudorapidity coverage
 CEN_max_mu         2.4     // muon chambers pseudorapidity coverage
+\end{verbatim}
+\end{quote}
+Definition of the sub-detector resolutions:
+\begin{quote}
+\begin{verbatim}
 # Energy resolution for electron/photon in central/endcap/fwd/zdc calos
 # \sigma/E = C + N/E + S/\sqrt{E}, E in GeV
 …
 \end{verbatim}
 \end{quote}
+Definitions related to the calorimetric cells:
 \begin{quote}
 \begin{verbatim}
 # Calorimetric towers
 TOWER_number         40
-### list of the edges of each tower in eta for eta>0 assuming
-###a symmetric detector in eta<0
-### the list starts with the lower edge of the most central tower
-### the list ends with the higher edged of the most forward tower
-### there should be NTOWER+1 values
 TOWER_eta_edges 0. 0.087 0.174 0.261 0.348 0.435 0.522 0.609 0.696 0.783
 .870 0.957 1.044 1.131 1.218 1.305 1.392 1.479 1.566 1.653
 …
 .000
-### list of the tower size in phi (in degrees), assuming that all
-### towers are similar in phi for a given eta value
-### the list starts with the phi-size of the most central tower (eta=0)
-### the list ends with the phi-size of the most forward tower
-### there should be NTOWER values
 TOWER_dphi 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 10
 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 20 20
 \end{verbatim}
 \end{quote}
+\texttt{TOWER\_eta\_edges} is the list of the edges in $\eta$ of all cells, in the $\eta>0$ hemisphere (the detector is supposed to be symmetric with respect to the $\eta=0$ plane, as well as around the $z$-axis). Starts with the lower edge of the most central tower (default: $\eta = 0$) and ends with the higher edge of the most forward tower.
+\texttt{TOWER\_dphi} lists the tower size in $\phi$ (in degree), assuming that all cells are similar in $\phi$ for a given $\eta$.\\
+Thresholds applied for storing the reconstructed objects in the final collections:
 \begin{quote}
 \begin{verbatim}
 …
 ZDC_gamma_E      20
 ZDC_n_E          50
+\end{verbatim}
+\end{quote}
+Definitions of variables related to the charged lepton isolation:
+\begin{quote}
+\begin{verbatim}
 # Charged lepton isolation. Pt and Et in GeV
 ISOL_PT          2.0  //minimal pt of tracks for isolation criteria
 …
 ISOL_Calo_ET     2.0  //minimal tower E_T for isolation criteria. 1E99 means "off"
 ISOL_Calo_Grid   3    //Grid size (N x N) for calorimetric isolation
+\end{verbatim}
+\end{quote}
+Definitions of variables related to the jet reconstruction:
+\begin{quote}
+\begin{verbatim}
 # General jet variable
 JET_coneradius   0.7  // generic jet radius
 …
 JET_Eflow        1    // Energy flow: perfect energy assumed in the tracker coverage.
                       // 1 is 'on' ; 0 is 'off'
+\end{verbatim}
+\end{quote}
+\begin{quote}
+\begin{verbatim}
 # Tagging definition
 BTAG_b           40    // b-tag efficiency (%)
 BTAG_mistag_c    10    // mistagging (%)
 BTAG_mistag_l    1     // mistagging (%)
+\end{verbatim}
+\end{quote}
+Switches for options
+\begin{quote}
+\begin{verbatim}
 # FLAGS
 FLAG_bfield      1     //1 to run the bfield propagation else 0
 …
 FLAG_FROG        1     //1 to run the FROG event display
 FLAG_LHCO        1     //1 to run the LHCO
+\end{verbatim}
+\end{quote}
+Parameters for the magnetic field simulation:
+\begin{quote}
+\begin{verbatim}
 # In case BField propagation allowed
 TRACK_radius      129   // radius of the BField coverage, in cm
 …
 TRACK_bfield_y    0     // Y component of the BField, in T
 TRACK_bfield_z    3.8   // Z component of the BField, in T
+\end{verbatim}
+\end{quote}
+Parameters related to the very forward detectors
+\begin{quote}
+\begin{verbatim}
 # Very forward detector extension, in pseudorapidity
 # if allowed
 VFD_min_zdc       8.3   // Zero-Degree neutral Calorimeter
 VFD_s_zdc         140   // distance of the ZDC, from the IP, in [m]
+\end{verbatim}
+\end{quote}
+\begin{quote}
+\begin{verbatim}
 #\textit{Hector} parameters
 RP_220_s          220     // distance of the RP to the IP, in meters
 …
 RP_cross_ang_x    142.5   // half-crossing angle in horizontal plane, in microrad
 RP_cross_ang_y    0       // half-crossing angle in vertical plane, in microrad
+\end{verbatim}
+\end{quote}
+Others parameters:
+\begin{quote}
+\begin{verbatim}
 # In case FROG event display allowed
 NEvents_FROG      100
 # Number of events to process
 NEvents           -1                    // -1 means 'all'
 # input PDG tables
 …
 \textbf{Analysis \texttt{Tree}} & & \\
 ~~~Tracks     & Collection of tracks                       & {\verb TRootTracks }\\
 ~~~CaloTower  & Calorimetric towers                        & {\verb TRootCalo }\\
+~~~CaloTower  & Calorimetric cells                         & {\verb TRootCalo }\\
 ~~~Electron   & Collection of electrons                    & {\verb TRootElectron }\\
 ~~~Photon     & Collection of photons                      & {\verb TRootPhoton }\\
 …
    \texttt{~~~float PhiCalo } &\texttt{ // particle azimuthal angle in rad when entering the calo }\\
    \texttt{~~~float EHoverEE }&\texttt{ // hadronic energy over electromagnetic energy }\\
    \texttt{~~~float EtRatio } &\texttt{ // calo Et in NxN-tower grid around the muon over the muon Et }\\
+   \texttt{~~~float EtRatio } &\texttt{ // calo Et in NxN-cell grid around the muon over the muon Et }\\
 \end{tabular}
 \end{quote}
 …
 \begin{tabular}{ll}
 \multicolumn{2}{l}{\textbf{Leaves in the \texttt{CaloTower} branch (\texttt{Analysis} tree)}}\\
     \texttt{~~~float Eta }     &\texttt{ // pseudorapidity of the tower }\\
     \texttt{~~~float Phi }     &\texttt{ // azimuthal angle of the tower in rad }\\
     \texttt{~~~float E }       &\texttt{ // tower energy in GeV }\\
     \texttt{~~~float E\_em }   &\texttt{ // electromagnetic component of the tower energy in GeV}\\
     \texttt{~~~float E\_had }  &\texttt{ // hadronic component of the tower energy in GeV}\\
     \texttt{~~~float ET }      &\texttt{ // tower transverse energy in GeV }\\
+    \texttt{~~~float Eta }     &\texttt{ // pseudorapidity of the cell }\\
+    \texttt{~~~float Phi }     &\texttt{ // azimuthal angle of the cell in rad }\\
+    \texttt{~~~float E }       &\texttt{ // cell energy in GeV }\\
+    \texttt{~~~float E\_em }   &\texttt{ // electromagnetic component of the cell energy in GeV}\\
+    \texttt{~~~float E\_had }  &\texttt{ // hadronic component of the cell energy in GeV}\\
+    \texttt{~~~float ET }      &\texttt{ // cell transverse energy in GeV }\\
 & \\
 \multicolumn{2}{l}{\textbf{Leaves in the \texttt{ETmis} branch (\texttt{Analysis} tree)}}\\
 …
 The hit position is computed from the center of the beam position, not from the edge of the detector.
+\subsection{Deeper description of jet algorithms}
+In this section, we briefly describe the differences between the six jet algorithms interfaced in \textit{Delphes}, via the FastJet utiliy~\citep{bib:FASTJET}. Jet algorithms differ in their sensitivity to soft particles or collinear splittings, and in their computing speed performances. The first three belong to the cone algorithm class while the last three are using a sequential recombination scheme. For all of them, the calorimetric cells are used as inputs for the jet clustering.
+\subsubsection*{Cone algorithms}
+\begin{enumerate}
+\item {\it CDF Jet Clusters}~\citep{bib:jetclu}: Basic cone reconstruction algorithm used by the \textsc{CDF} experiment in Run II). All cells lying in a circular cone around the jet axis with a transverse energy $E_T$ higher than a given threshold are used to seed the jet candidates. This algorithm is fast but sensitive to both soft particles and collinear splittings.
+\item {\it CDF MidPoint}~\citep{bib:midpoint}: Cone reconstruction algorithm developed for the \textsc{CDF} Run II to reduce infrared and collinear sensitivities compared to purely seed-based cone by adding `midpoints' (energy barycentres) in the list of cone seeds.
+\item {\it Seedless Infrared Safe Cone}~\citep{bib:SIScone}: The \textsc{SISC}one algorithm is simultaneously insensitive to additional soft particles and collinear splittings, and fast enough to be used in experimental analysis.
+\end{enumerate}
+\subsubsection*{Recombination algorithms}
+The three sequential recombination jet algorithms are safe with respect to soft radiations (\textit{infrared}) and collinear splittings. They rely on recombination schemes where calorimeter cell pairs are successively merged.
+The definitions of the jet algorithms are similar except for the definition of the \textit{distances} $d$ used during the merging procedure. Two such variables are defined: the distance $d_{ij}$ between each pair of cells $(i,j)$, and a variable $d_{iB}$ (\textit{beam distance}) depending on the transverse momentum of the cell $i$.
+The jet reconstruction algorithm browses the calorimetric cell list. It starts by finding the minimum value $d_\textrm{min}$ of all the distances $d_{ij}$ and $d_{iB}$. If $d_\textrm{min}$ is a $d_{ij}$, the cells $i$ and $j$ are merged into a single cell with a four-momentum $p^\mu = p^\mu (i) + p^\mu (j)$ (\textit{E-scheme recombination}). If $d_\textrm{min}$ is a $d_{iB}$, the cell is declared as a final jet and is removed from the input list. This procedure is repeated until no cells are left in the input list. Further information on these jet algorithms is given here below, using $k_{ti}$, $y_{i}$ and $\phi_i$ as the transverse momentum, rapidity and azimuth of calorimetric cell $i$ and $\Delta R_{ij}= \sqrt{(y_i-y_j)^2+(\phi_i-\phi_j)^2}$ as the jet-radius parameter:
+\begin{enumerate}[start=4]
+\item {\it Longitudinally invariant $k_t$ jet}~\citep{bib:ktjet}, with
+  $d_{ij} = \min(k_{ti}^2,k_{tj}^2) \times \frac{\Delta R_{ij}^2}{R^2}$ and $d_{iB}=k_{ti}^2$,
+\item {\it Cambridge/Aachen jet}~\citep{bib:aachen}, with $d_{ij} = \frac{\Delta R_{ij}^2}{R^2}$ and $d_{iB}=1$,
+\item {\it Anti $k_t$ jet}~\citep{bib:antikt}, where hard jets are exactly circular in the $(y,\phi)$ plane:
+$d_{ij} =  \min(1/k_{ti}^2,1/k_{tj}^2) \times \frac{\Delta R_{ij}^2}{R^2}$ and $d_{iB}=\frac{1}{k_{ti}^2}$.
+\end{enumerate}
 \subsection{Running an analysis on your \textit{Delphes} events}
 …
 \paragraph{9th column (\texttt{had/em})}
 For jets, electrons and photons, the ninth column is the ration between hadronic and electromagnetic energies in the calorimetric towers associated to the object. This is always \texttt{0} for missing transverse energy.
+For jets, electrons and photons, the ninth column is the ration between hadronic and electromagnetic energies in the calorimetric cells associated to the object. This is always \texttt{0} for missing transverse energy.
 For muons, this number (\texttt{aaa.bb}) reports two values related to the muon isolation (section \ref{sec:isolation}). The integer part (\texttt{aaa}) is transverse momentum sum $P_T$ (in GeV/$c$) and the fractional part (\texttt{bb}) is the energy ratio $\rho_\mu$.

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