Measurements of tt-bar cross sections in association with b jets and inclusive jets and their ratio using dilepton final states in pp collisions at sqrt(s) = 13 TeV

TL;DR

This paper reports precise measurements of top-antitop quark pair production with additional b jets and inclusive jets at 13 TeV, providing key data to test Standard Model predictions and improve understanding of top quark processes.

Contribution

First measurement of the ratio of tt-bar bb-bar to tt-bar jj cross sections in dilepton final states at 13 TeV with detailed systematic analysis.

Findings

Measured ratio sigma[tt-bar bb-bar]/sigma[tt-bar jj] = 0.022 +/- 0.003 (stat) +/- 0.006 (syst)

Measured sigma[tt-bar bb-bar] = 4.0 +/- 0.6 (stat) +/- 1.3 (syst) pb

Measured sigma[tt-bar jj] = 184 +/- 6 (stat) +/- 33 (syst) pb

Abstract

The cross sections for the production of tt-bar bb-bar and tt-bar jj events and their ratio sigma[tt-bar bb-bar]/sigma[tt-bar jj] are measured using data corresponding to an integrated luminosity of 2.3 inverse femtobarns collected in pp collisions at sqrt(s) = 13 TeV with the CMS detector at the LHC. Events with two leptons (e or mu) and at least four reconstructed jets, including at least two identified as b quark jets, in the final state are selected. In the full phase space, the measured ratio is 0.022 +/- 0.003 (stat) +/- 0.006 (syst), the cross section sigma[tt-bar bb-bar] is 4.0 +/- 0.6 (stat) +/- 1.3 (syst) pb and sigma[tt-bar jj] is 184 +/- 6 (stat) +/- 33 (syst) pb. The measurements are compared with the standard model expectations obtained from a POWHEG simulation at next-to-leading-order interfaced with PYTHIA.

Tables

Process	\EE	\MM	${\text{Pe}}^{\pm }{\text{PGm}}^{\mp }$	All
$\text{ttbar}\text{bbbar}$	$\mathrm{6.3\pm 0.4}$	$\mathrm{8.6\pm 0.4}$	$\mathrm{24\pm 1}$	$\mathrm{39\pm 1}$
$\text{ttbar}\text{PQb}\text{cmsSymbolFace}j$	$\mathrm{16\pm 1}$	$\mathrm{21\pm 1}$	$\mathrm{57\pm 2}$	$\mathrm{95\pm 2}$
$\text{ttbar}\text{PQc}\text{PAQc}$	$\mathrm{7.7\pm 0.4}$	$\mathrm{11\pm 1}$	$\mathrm{27\pm 1}$	$\mathrm{46\pm 1}$
$\text{ttbar}\text{cmsSymbolFace}LF$	$\mathrm{157\pm 2}$	$\mathrm{220\pm 2}$	$\mathrm{596\pm 3}$	$\mathrm{972\pm 4}$
\ttbar  others	$\mathrm{18\pm 1}$	$\mathrm{19\pm 1}$	$\mathrm{61\pm 1}$	$\mathrm{99\pm 1}$
\ttbarV	$\mathrm{2.5\pm 0.1}$	$\mathrm{3.2\pm 0.2}$	$\mathrm{7.3\pm 0.2}$	$\mathrm{14\pm 1}$
Single \PQt	$\mathrm{6.6\pm 0.8}$	$\mathrm{8.4\pm 0.8}$	$\mathrm{23\pm 2}$	$\mathrm{39\pm 2}$
$\text{Z}$+jets	${0.8}_{-0.8}^{+1.0}$	$\mathrm{5.4\pm 1.5}$	$\mathrm{0.6\pm 0.5}$	$\mathrm{6.8\pm 1.9}$
Total	$\mathrm{215\pm 2}$	$\mathrm{297\pm 3}$	$\mathrm{796\pm 4}$	$\mathrm{1311\pm 6}$
Data	186	288	682	1156

Equations

$$I_{\text{rel}}=\frac{\sum {\text{pt}}^{\text{charged hadron}}+\sum {\text{pt}}^{\text{neutral hadron}}+\sum {\text{pt}}^{\text{photon}}}{{\text{pt}}^{\text{lepton}}}.$$

$$\mathcal{M}(N_{\text{ttbar}\text{cmsSymbolFace}jj},R)=N_{\text{ttbar}\text{cmsSymbolFace}jj}\left[R{\mathcal{F}}_{\text{ttbar}\text{bbbar}}^{\text{norm}}+R^{\prime }{\mathcal{F}}_{\text{ttbar}\text{PQb}\text{cmsSymbolFace}j}^{\text{norm}}+(1-R-R^{\prime }){\mathcal{F}}_{\text{ttbar}\text{cmsSymbolFace}LF+\text{ttbar}\text{PQc}\text{PAQc}}^{\text{norm}}\right]+N_{\text{ttbar}\text{cmsSymbolFace}jj}{f}_{\text{ttbar}\text{ others}}+N_{\text{bkg}},$$

$${({\sigma }_{\text{ttbar}\text{bbbar}}/{\sigma }_{\text{ttbar}\text{cmsSymbolFace}jj})}^{\text{vis}}=0.024\pm 0.003\text{stat}\pm 0.007\text{syst}.$$

$${\sigma }_{\text{ttbar}\text{bbbar}}/{\sigma }_{\text{ttbar}\text{cmsSymbolFace}jj}=0.022\pm 0.003\text{stat}\pm 0.006\text{syst}.$$

Full text

0.1 Introduction

Since the discovery of the Higgs boson [1, 2, 3], its properties have been measured and compared to the standard model (SM) prediction [4, 5, 6, 7, 8, 9]. However, the coupling of the top quark to the Higgs boson remains to be determined. Although it appears indirectly through loops in the gluon–gluon fusion production process and in the $\PH\to\gamma\gamma$ decay channel, a direct measurement has yet to be completed. One of the most promising channels for a direct measurement of the top quark Yukawa coupling in the SM is the production of the Higgs boson in association with a \ttbarpair ($\ttbar\PH$), where the Higgs boson decays to \bbbar, thus leading to a $\ttbar\bbbar$ final state. This final state, which has not been observed yet [10], has an irreducible nonresonant background from the production of a top quark pair in association with a b quark pair produced via gluon splitting ($\Pg\to\bbbar$).

Calculations of the inclusive production cross section for \ttbarevents with additional jets have been performed to next-to-leading-order (NLO) precision for proton–proton centre-of-mass energies of 7, 8, and 13\TeV [11]. The dominant uncertainties in these calculations are from the choice of the factorization ($\mu_{\mathrm{F}}$) and renormalization ($\mu_{\mathrm{R}}$) scales [12, 13], and are complicated by the presence of two very different scales in this process: the top quark mass and the jet transverse momentum (\pt). Therefore, experimental measurements of production cross sections $\Pp\Pp\to\ttbar\cmsSymbolFace{jj}\ (\sigma_{\ttbar\cmsSymbolFace{jj}})$ and $\Pp\Pp\to\ttbar\bbbar\ (\sigma_{\ttbar\bbbar})$ can provide an important test of NLO quantum chromodynamics (QCD) theory calculations and important input for describing the main background in the search for the $\ttbar\PH$ process. Previous cross section and ratio measurements at $\sqrt{s}=7$ and 8\TeVhave been reported by the CMS [14, 15] and ATLAS Collaborations [16].

In this Letter, the measurements of the cross sections $\sigma_{\ttbar\bbbar}$ and $\sigma_{\ttbar\cmsSymbolFace{jj}}$ and their ratio are presented using a data sample of pp collisions collected at a centre-of-mass energy of 13\TeVat the CERN LHC by the CMS experiment, and corresponding to an integrated luminosity of 2.3\fbinv [17]. Events are selected with the final state consisting of two leptons ($\Pe$ or $\PGm$) and at least four reconstructed jets, of which at least two are identified as b quark jets. The cross section ratio is measured with a smaller systematic uncertainty exploiting the partial cancellation of uncertainties.

0.2 The CMS detector and event simulation

The central feature of the CMS apparatus is a superconducting solenoid of 6\unitm internal diameter, providing a magnetic field of 3.8\unitT. Within the solenoid volume are a silicon pixel and strip tracker, a lead tungstate crystal electromagnetic calorimeter (ECAL), and a brass and scintillator hadron calorimeter (HCAL), each composed of a barrel and two endcap sections. Forward calorimeters extend the pseudorapidity ($\eta$) coverage provided by the barrel and endcap detectors. Muons are reconstructed in gas-ionization detectors embedded in the steel flux-return yoke outside the solenoid. A more detailed description of the CMS detector, together with a definition of the coordinate system used and the relevant kinematic variables, can be found in Ref. [18].

The Monte Carlo (MC) simulated samples for the \ttbarsignal are generated by the \POWHEG (v2) event generator [19, 20, 21] at NLO, interfaced with \PYTHIA(v8.205) [22, 23] using the tune CUETP8M1 [24] to provide the showering of the partons and to match soft radiation with the contributions from the matrix elements (MEs). The NNPDF3.0 [25] set of the parton distribution functions (PDFs) is used. The \MADGRAPH (v5.1.5.11) event generator [26] with MEs at leading order (LO), allowing up to three additional partons, including b quarks, and the \MGvATNLO (v2.2.2) event generator [27] are both used for cross-checks and studies of systematic uncertainties. The \ttbarsamples are normalized to the next-to-next-to-leading-order (NNLO) cross section calculation [28]. The $\PW$+jets and $\cPZ/\gamma^{*}$+jets processes are simulated in \MGvATNLO and are normalized to their NNLO cross sections [29]. The single top quark associated production with a $\PW$ boson ($\Pp\Pp\to\PQt\PW$ and $\Pp\Pp\to\PAQt\PW$) is simulated in the five-flavour scheme in \POWHEG(v1) at NLO and normalized to an approximate NNLO cross section calculation [30], while the $t$-channel single top quark events are simulated in the four-flavour scheme in \MGvATNLO. The multijet production is modelled in \PYTHIAwith LO MEs. The CMS detector response is simulated using \GEANTfour (v9.4) [31]. The events in simulation include the effects of additional interactions in the same or nearby bunch crossings (pileup) and are weighted according to the vertex distribution observed in data. The number of pileup interactions in data is estimated from the measured bunch-to-bunch instantaneous luminosity and the total inelastic cross section [32].

0.3 Definition of signal events

Measurements are reported for two different regions of the phase space: the visible and the full phase space. The result in the visible phase space is measured at the particle level, using the stable particles after the hadronization, to reduce the possible theoretical and modelling uncertainties, while the purpose of performing the result in the full phase space is to facilitate comparisons to NLO calculations or measurements in other decay modes.

To define the visible phase space, all $\ttbar\bbbar$ final-state particles except the neutrinos, \iethe charged leptons and jets originating from the decays of the top quarks, as well as the two additional b quark jets (“b jets”), are required to be within the experimentally accessible kinematic region. The leptons must have $\pt>20\GeV$, and $\abs{\eta}<2.4$. Electrons or muons originating from the leptonic decays of $\Pgt$ leptons produced in $\PW\to\Pgt\Pgn$ decays are included. The particle-level jets are obtained by combining all final-state particles, excluding neutrinos, at the generator level with an anti-\ktclustering algorithm [33] with a distance parameter of 0.4 and are required to satisfy $\abs{\eta}<2.5$ and $\pt>20$\GeV, which is lower than the reconstructed minimum jet \ptdue to jet resolution – to have all events that pass the reconstructed jet \ptin the visible phase space. Jets that are within $\DR=\sqrt{\smash[b]{(\Delta\phi)^{2}+(\Delta\eta)^{2}}}=0.5$ units of an identified electron or muon are removed, where $\Delta\phi$ and $\Delta\eta$ are the differences in azimuthal angle and pseudorapidity between the directions of the jet and the lepton. To identify the b and c quark jets (“c jets”) unambiguously, the b and c hadron momenta are scaled down to a negligible value and included in the jet clustering (so called “ghost matching”) [34]. The b and c jets are then identified by the presence of the corresponding “ghost” hadrons among the jet constituents.

Simulated events are categorized as coming from the $\ttbar\cmsSymbolFace{jj}$ process if they contain at least four particle-level jets, including at least two jets originating from b quarks, and two leptons ($\ttbar\cmsSymbolFace{jj}\to\PQb\PWp\PAQb\PWm\mathrm{jj}\to\PQb{\ell}^{+}\Pgn\PAQb{\ell}^{-}\Pagn\mathrm{jj}$). The $\ttbar\cmsSymbolFace{jj}$ sample contains four components according to the number of b and c jets in addition to the two b jets required from the top quark decays. The four components are the $\ttbar\bbbar$ final state with two b jets, the $\ttbar\PQb\cmsSymbolFace{j}$ final state with one b jet and one lighter-flavour jet, the $\ttbar\PQc\PAQc$ final state with two c jets, and the $\ttbar\cmsSymbolFace{LF}$ final state with two light-flavour jets (from a gluon or u, d, or s quark) or one light-flavour jet and one c jet. The $\ttbar\PQb\cmsSymbolFace{j}$ final state mainly originates from the merging of two b jets or the loss of one of the b jets caused by the acceptance requirements.

0.4 Event selection

The events are recorded at $\sqrt{s}=13$\TeVusing a dilepton trigger [35] that requires the presence of two isolated leptons ($\Pe$ or $\PGm$) both with \ptlarger than 17\GeV.

The particle-flow (PF) event algorithm [36, 37] reconstructs and identifies each individual particle with an optimized combination of information from the various elements of the CMS detector. The energy of photons is directly obtained from the ECAL measurement. The energy of electrons is determined from a combination of the electron momentum at the primary interaction vertex as determined by the tracker, the energy of the corresponding ECAL cluster, and the energy sum of all bremsstrahlung photons spatially compatible with originating from the electron track. The energy of muons is obtained from the curvature of the corresponding track reconstructed by combining information from the silicon tracker and the muon system [38]. The energy of charged hadrons is determined from a combination of their momenta measured in the tracker and the matching ECAL and HCAL energy deposits, corrected for zero-suppression effects and for the response function of the calorimeters to hadronic showers. Finally, the energy of neutral hadrons is obtained from the corresponding corrected ECAL and HCAL energy.

The leptons and all charged hadrons that are associated with jets are required to originate from the primary vertex, defined as the vertex with the highest $\sum{\pt^{2}}$ of its associated tracks. Muon candidates are further required to have a high-quality fit including a minimum number of hits in both systems. Requirements on electron identification variables based on shower shape and track-cluster matching are further applied to the reconstructed electron candidates [39, 40, 41]. Muons and electrons must have $\pt>20$\GeVand $\abs{\eta}<2.4$.

To reduce the background contributions of muons or electrons from semileptonic heavy-flavour decays, relative isolation criteria are applied. The relative isolation parameter, $I_{\text{rel}}$, is defined as the ratio of the summed \ptof all objects in a cone of $\DR=0.3$ ($\DR=0.4$) units around the electron (muon) direction to the lepton \pt. Different cone sizes for electron and muon are used to maximize the sensitivity. The objects considered are the charged hadrons associated with the primary vertex as well as the neutral hadrons and photons, whose energies are corrected to take into account pileup effects. Thus,

[TABLE]

The muon candidates are required to have $I_{\text{rel}}<0.15$. For the electron candidates, different $I_{\text{rel}}$ thresholds (0.077 or 0.068) are applied depending on the pseudorapidity of the candidate ($\abs{\eta}<1.48$ or $1.48\leq\abs{\eta}<2.40$). These thresholds are obtained from a multivariate analysis technique and result from the considerable differences in both the ECAL and the tracker in the two pseudorapidity regions. The efficiencies for the above lepton identification requirements are measured using $\Z$ boson candidates in data with a dilepton invariant mass between 70 and 130\GeV, and are compared with the values from the simulation. The differences between the two evaluations are applied as a correction to the simulation.

The event selection requires the presence of two isolated opposite-sign leptons of invariant mass $M_{\ell\ell}>12$\GeV. Lepton pairs of the same flavour (\EE, \MM) are rejected if their invariant mass is within 15\GeVof the $\Z$ boson mass. The missing transverse momentum vector \ptvecmissis defined as the projection on the plane perpendicular to the beams of the negative vector sum of the momenta of all reconstructed PF candidates in the event. Its magnitude is referred to as $\ptmiss$. In the same-flavour channels, remaining backgrounds from $\Z$+jets processes are suppressed by demanding $\ptmiss>30$\GeV. For the $\Pe^{\pm}\PGm^{\mp}$ channel, no $\ptmiss$ requirement is applied.

Jets are reconstructed using the same anti-\ktclustering algorithm as particle-level jets in the simulations, with the PF candidates as input particles. The jet momentum is determined as the vectorial sum of all PF candidate momenta in the jet and is found from simulation to be within 5 to 10% of the true momentum over the whole \ptspectrum and detector acceptance. An offset correction is applied to jet energies to take into account the contribution from pileup interactions. Jet energy corrections are derived from simulation and confirmed with in situ measurements of the energy balance in dijet and photon+jet events [42]. Additional selection criteria are applied to each event to remove spurious jet-like features originating from isolated noise patterns in certain HCAL regions. The event must contain at least four reconstructed jets with $\pt>30$\GeVand $\abs{\eta}<2.4$, of which at least two jets must be identified as b jets, using the combined secondary vertex (CSV) algorithm (v2), which combines secondary vertex information with lifetime information of single tracks to produce a b tagging discriminator [43]. A b tagging requirement on this discriminator is applied, which has an efficiency of about 60–70% for b jets and a misidentification probability of 1% for light-flavour jets and 15–20% for c-flavour jets [44].

Differences in the b tagging efficiencies between data and simulation [43] are accounted for by reweighting the shape of the CSV b tagging discriminator distribution in the simulation to match that in the data. Data/simulation \pt- and $\eta$-dependent correction factors are derived from the control samples separately for light- and heavy-flavour jets, that are described in Section 0.6.

The diboson, W+jets and multijet contributions are found to be negligible after the full event selection. The $\Z$+jets background is estimated from data using control samples enriched in $\Z$ boson events.

Table 0.4 gives the predicted number of events for each physics process and for each lepton category, as well as a comparison of the total number of events expected from the simulation and observed in data. Since the full event selection requires at least two b-tagged jets, a condition which is usually satisfied by \ttbarevents, only 5% of the events are from non-\ttbarprocesses. The $\ttbar\PQb\cmsSymbolFace{j}$ final state is predominantly composed of $\ttbar\bbbar$ events where there is one lost b jet due to acceptance requirements (73% of $\ttbar\PQb\cmsSymbolFace{j}$ events). The background contribution from \ttbarevents that fail the visible phase space requirements is labelled “\ttbarothers”. The number of observed events with four or more reconstructed jets is lower than the prediction from the simulation, a condition that is also observed in the lepton+jets decay mode [45].

0.5 Cross section measurements

The first and the second jets in decreasing order of the b tagging discriminator usually (in 85% of $\ttbar\cmsSymbolFace{jj}$ events) correspond to the b jets from the decays of top quarks, and hence these jets provide no discriminating power between $\ttbar\bbbar$ and $\ttbar\cmsSymbolFace{jj}$ events. The third and the fourth jets from $\ttbar\cmsSymbolFace{jj}$ events are mostly light-flavour jets, while these are heavy-flavour jets for $\ttbar\bbbar$ events. The normalized 2D distributions of the discriminators from simulation for the third and the fourth jets are shown in Fig. 1. These 2D distributions are used to separate $\ttbar\bbbar$ events from other processes. To extract the ratio of the number of $\ttbar\bbbar$ events to $\ttbar\cmsSymbolFace{jj}$ events, a binned maximum-likelihood fit is performed on the 2D distribution of the CSV b tagging discriminators of the third and the fourth jets, where the three event categories $\Pe^{\pm}\Pe^{\mp}$, $\Pe^{\pm}\PGm^{\mp}$, and $\PGm^{\pm}\PGm^{\mp}$ are merged.

The number of $\ttbar\cmsSymbolFace{jj}$ events and the ratio of the numbers of $\ttbar\bbbar$ events to $\ttbar\cmsSymbolFace{jj}$ events are free parameters in the fit. The $\ttbar\PQc\PAQc$ and $\ttbar\cmsSymbolFace{LF}$ processes have similar 2D distributions so their contributions are combined based on the MC simulation.

The likelihood function is constructed as the product over all bins of a Poisson probability with a mean defined in each bin by

[TABLE]

where $\mathcal{F}_{\ttbar\bbbar}^{\text{norm}}$, $\mathcal{F}_{\ttbar\PQb\cmsSymbolFace{j}}^{\text{norm}}$, and $\mathcal{F}_{\ttbar\cmsSymbolFace{LF}+\ttbar\PQc\PAQc}^{\text{norm}}$ are the normalized expectations for each bin of $\ttbar\bbbar$, $\ttbar\PQb\cmsSymbolFace{j}$, and the combination of $\ttbar\cmsSymbolFace{LF}$ and $\ttbar\PQc\PAQc$, respectively. The parameter $N_{\ttbar\cmsSymbolFace{jj}}$ denotes the number of the $\ttbar\cmsSymbolFace{jj}$ events from the fit. The quantity $f_{\ttbar\text{ others}}$ reflects the fraction of other $\ttbar$ processes in the $\ttbar\cmsSymbolFace{jj}$ sample as calculated in simulation ($\ttbar\text{ others}$ divided by the sum of the $\ttbar\cmsSymbolFace{jj}$ components in Table 0.4). The other backgrounds, such as \ttbarV (V = W or Z) and single top quark processes are fixed to the simulation expectations, while the $\Z$+jets background is fixed to its estimation from control samples in data. This remaining background not from the $\ttbar$ process is labelled $N_{\text{bkg}}$. The parameter $R$ is the ratio of the number of $\ttbar\bbbar$ events with respect to the number of $\ttbar\cmsSymbolFace{jj}$ events, and $R^{\prime}$ is the fraction of $\ttbar\PQb\cmsSymbolFace{j}$ events at the reconstruction level and constrained to the ratio of the number of the $\ttbar\PQb\cmsSymbolFace{j}$ events to $\ttbar\bbbar$ events. It is fixed to 2.43 as calculated from the MC simulation (\POWHEGinterfaced with \PYTHIA). The effect of this assumption is estimated as a systematic uncertainty in Section 0.6. Values for $N_{\ttbar\cmsSymbolFace{jj}}$ of $950\pm 30$ events and $R$ of $0.056\pm 0.008$ are obtained from the fit. The correlation coefficient between the two parameters is 0.002.

The result obtained for $R$ is corrected to account for the different selection efficiencies for the two processes. The event selection efficiencies, defined as the number of $\ttbar\bbbar$ and $\ttbar\cmsSymbolFace{jj}$ events after the full event selection divided by the number of events in the corresponding visible phase space, are 27% and 12%, respectively. For the $\ttbar\bbbar$ process, there are at least 4 b jets in the events, therefore, it is easier to fulfill the requirement of at least two b-tagged jets than the $\ttbar\cmsSymbolFace{jj}$ process.

Figure 2 shows the comparisons of the b tagging discriminator distributions of the third and the fourth jets in the events from data and simulation, where the simulated histograms have been scaled to the fit result.

The b-tagged jet multiplicity distribution in Fig. 3 shows the comparison between data and the simulation after the requirement of at least four jets, together with the ratio of the number of data events to the expectation in the lower panel, where the simulated histograms have been scaled to the fit result.

The $\ttbar\bbbar$ and $\ttbar\cmsSymbolFace{jj}$ cross sections in the visible phase space are calculated using the relationship $\sigma_{\text{visible}}=N/(\epsilon\mathcal{L})$, where $\mathcal{L}$ is the integrated luminosity, $N$ is the number of events from the fit result, and $\epsilon$ is the efficiency for each process. For the purpose of comparing with the theoretical prediction and the measurements in the other decay modes, the cross sections in the full phase space are extrapolated from the cross sections in the visible phase space using the relation $\sigma_{\text{full}}=\sigma_{\text{visible}}/\mathcal{A}$, where $\mathcal{A}$ is the acceptance, defined as the number of events in the corresponding visible phase space divided by the number of events in the full phase space. The acceptances are calculated based on the \POWHEGsimulation and are 2.2% and 2.0% for $\ttbar\bbbar$ and $\ttbar\cmsSymbolFace{jj}$, respectively, including the leptonic branching fraction of both W bosons [46].

0.6 Estimation of systematic uncertainties

The systematic uncertainties are determined separately for the $\ttbar\bbbar$ and $\ttbar\cmsSymbolFace{jj}$ cross sections, and their ratio. In the ratio, many systematic effects cancel, specifically normalization uncertainties, such as the ones related to the measurement of the integrated luminosity and the lepton identification, including trigger efficiencies, since they are common to both processes. The various systematic uncertainties in the measured values are shown in Table 0.6 for the visible phase space.

The systematic uncertainties associated with the b tagging efficiency for heavy- and light-flavour jets are studied separately, varying their values within the corresponding uncertainties. The b-flavour correction factors are obtained using \ttbarenriched events by tagging one b jet and probing the other b jet. Their dominant uncertainty comes from the contamination when one of the b jets is not reconstructed [47] (indicated as “b quark flavour” in Table 0.6). The light-flavour jet correction factors are determined from $\Z$+jets enriched events with at least two jets (indicated as “light flavour” in Table 0.6). The uncertainty arises because in this control sample of $\Z$+jets, the contamination from the $\Z$+\bbbarprocess is not well modelled. The correction factor for c jets is not measured, owing to the limited amount of data, and is assumed to be unity with an uncertainty twice as large as for b jets [43] (indicated as “c quark flavour” in Table 0.6). In the correction factor evaluation, the statistical uncertainty, which can arise owing to low event yields in certain regions, \egat values of the b tagging discriminator near one, is also taken into account.

The b tagging discriminator can also be affected by the jet energy scale (JES) variations [42] since the efficiency correction changes through its \ptdependence. The corresponding systematic uncertainty is obtained by varying the JES correction within its uncertainty and repeating the whole analysis. The uncertainty induced by the jet energy resolution (JER) is assessed by smearing the jet energy resolution in simulation by an additional uncertainty dependent on $\eta$ of about 10% [42].

The ratio of $\ttbar\bbbar$ events with respect to $\ttbar\PQb\cmsSymbolFace{j}$ events is based on the \POWHEGMC simulation. The uncertainty arising from this rate is evaluated by comparing the reference value (\POWHEG) with that of a \MGvATNLO sample, and \POWHEGsamples with different $\mu_{\mathrm{F}}$ and $\mu_{\mathrm{R}}$ scales in the ME and parton shower (PS) calculations.

The contributions from $\Z$+jets and single top quark processes are small, and the 2D b tagging discriminator distributions from these backgrounds are similar to those of the $\ttbar\cmsSymbolFace{LF}$ component. Therefore, these backgrounds do not affect the measurement significantly. The uncertainty caused by mismodelling of these backgrounds is assessed by varying the contribution to cover the uncertainty in the single top quark production cross section (indicated as “Background modelling” in Table 0.6). An uncertainty to account for the modelling of the $\ttbar\PQc\PAQc$ fraction by simulations is also assigned by varying the contribution by 50% in the fit. This is derived from the theoretical uncertainty on the $\ttbar\cmsSymbolFace{jj}$ cross section. For the efficiency of $\ttbar\cmsSymbolFace{jj}$ events, the uncertainty owing to the heavy-flavour fraction is negligible because of their small fraction.

The systematic uncertainty in the lepton identification is calculated by varying the correction factor for the efficiency within its uncertainty, as derived from $\Z$ boson candidates as a function of lepton $\eta$ and $\pt$, and also taking into account the different phase space between $\Z$ boson and \ttbarevents.

The systematic uncertainty in the number of pileup events is estimated by varying the total inelastic cross section by 5% to cover all of the uncertainties in the modelling of the pileup [32].

The dependence of the correction factor at the particle level on the assumptions made in the MC simulation is another source of systematic uncertainty: the generators \POWHEGand \MGvATNLO are compared and the difference in the efficiency is taken as systematic uncertainty. The uncertainties from the $\mu_{\mathrm{F}}$ and $\mu_{\mathrm{R}}$ scales at the ME level are estimated by making use of a weighting scheme implemented in \POWHEGto vary the scales by a factor of two up and down with respect to their reference values $\mu_{\mathrm{F}}=\mu_{\mathrm{R}}=\sqrt{\smash[b]{m_{\PQt}^{2}+p_{\mathrm{T},\PQt}^{2}}}$, where $m_{\PQt}$ is 172.5\GeV, with $p_{\mathrm{T},\PQt}$ being the top quark transverse momentum. The uncertainties from the $\mu_{\mathrm{F}}$ and $\mu_{\mathrm{R}}$ scales at the PS level are assessed by using additional simulations where the scales are changed by a factor of two up and down relative to their reference values. In simulation, event weights are calculated that represent the usage of the uncertainty eigenvector sets of the PDF. The uncertainties in the PDFs are accounted for by using these various event weights. The uncertainty from the modelling of jet multiplicity, in particular, the mismodelling for events with more than five jets, is also taken into account. It is estimated to be 5% by comparing the rates of high-multiplicity events in data and simulation.

The size of the MC sample used for $\ttbar\bbbar$ simulation being limited, the uncertainty from the statistical fluctuations in the simulated event samples is assessed by repeating the fit with the method described in Ref. [48]. The difference of 1.5% in the result is accounted for in the systematic uncertainty.

In addition to the theoretical and modelling uncertainties described above, the uncertainty coming from the modelling of the top quark \ptdistribution in the ME calculations is taken into account. The uncertainty is calculated by taking the difference in shape between the parton-level \ptspectrum from the ME generator and the unfolded \ptspectrum from the data [49]. The uncertainty due to the top quark \ptmodelling is negligible in this analysis, as shown in Table 0.6.

Adding all these contributions in quadrature gives a total systematic uncertainty of 28% in the cross section ratio, with the dominant contributions coming from the b tagging efficiency and the misidentification of light- and c-flavoured partons, followed by the matching scale systematic uncertainties.

The uncertainty in $\sigma_{\ttbar\cmsSymbolFace{jj}}$ is significantly smaller than that in $\sigma_{\ttbar\bbbar}$ since the measurement of the latter requires the identification of multiple b jets. The uncertainty in $\sigma_{\ttbar\bbbar}$ is larger than that for the cross section ratio, since the uncertainties that are common between $\ttbar\bbbar$ and $\ttbar\cmsSymbolFace{jj}$, such as the JES uncertainty, partially or completely cancel in the ratio.

When extrapolating the measurements from the visible phase space to the full phase space, the systematic uncertainty in the acceptance is included. The effect of the MC modelling of the acceptance is estimated by comparing the results between \MGvATNLO and \POWHEG. This uncertainty amounts to 4% for each of the cross section measurements and 1% for the cross section ratio.

0.7 Results

After accounting for all corrections and systematic effects, the cross section ratio $\sigma_{\ttbar\bbbar}$/$\sigma_{\ttbar\cmsSymbolFace{jj}}$ is measured in the visible phase space from a fit to the measured CSV b tagging discriminator distributions. The measured cross section ratio in the visible phase space for events with particle-level jets is

[TABLE]

The result is obtained in the visible phase space, defined as events having two leptons with $\pt>20\GeV$ and $\abs{\eta}<2.4$, plus at least four jets, including at least two b jets with $\pt>20\GeV$ and $\abs{\eta}<2.5$. The cross section ratio in the full phase space that uses the acceptance correction described in Section 0.5 is

[TABLE]

The predicted values from \POWHEGare $0.014\pm 0.001$ and $0.012\pm 0.001$ for the visible and full phase space, respectively, where the uncertainty in the simulation is the sum in quadrature of the statistical, and the $\mu_{\mathrm{F}}$/$\mu_{\mathrm{R}}$ scale systematic uncertainties. The prediction obtained from \POWHEGsimulation (interfaced with \PYTHIA) underpredicts the measured cross section ratio by a factor of 1.8, but it is compatible with the observation within two standard deviations. The measured cross sections in the visible and the full phase space are presented in Table 0.7.

0.8 Summary

Measurements of the cross sections $\sigma_{\ttbar\bbbar}$ and $\sigma_{\ttbar\cmsSymbolFace{jj}}$ and their ratio $\sigma_{\ttbar\bbbar}$/$\sigma_{\ttbar\cmsSymbolFace{jj}}$ are presented using a data sample recorded in pp collisions at $\sqrt{s}=13$\TeV, corresponding to an integrated luminosity of 2.3\fbinv. The cross section ratio has been measured in a visible phase space region using the dilepton decay mode of \ttbarevents and corrected to the particle level, corresponding to the detector acceptance. The measured cross section ratios in the visible and the full phase space are $\sigma_{\ttbar\bbbar}/\sigma_{\ttbar\cmsSymbolFace{jj}}=0.024\pm 0.003\stat\pm 0.007\syst$ and $\sigma_{\ttbar\bbbar}/\sigma_{\ttbar\cmsSymbolFace{jj}}=0.022\pm 0.003\stat\pm 0.006\syst$, respectively, where a minimum transverse momentum for the particle-level jets of 20\GeVis required. The $\ttbar\PH$ contribution, being negligible, is not removed from data. Theoretical ratios predicted from the \POWHEGsimulation (interfaced with \PYTHIA) are $0.014\pm 0.001$ for the visible and $0.012\pm 0.001$ for the full phase space, which are lower than the measured values but consistent within two standard deviations. The individual cross sections $\sigma_{\ttbar\bbbar}=4.0\pm 0.6\stat\pm 1.3\syst$\unitpb and $\sigma_{\ttbar\cmsSymbolFace{jj}}=184\pm 6\stat\pm 33\syst$\unitpb have also been measured. These results, in particular the ratio of the cross sections, provide important information for the $\ttbar\PH$ search, permitting the reduction of a dominant systematic uncertainty that derives from the uncertainty in the $\ttbar\bbbar$ background. They can also be used as a figure of merit for testing the validity of next-to-leading-order QCD calculations at $\sqrt{s}=13$\TeV.

Acknowledgements.

We congratulate our colleagues in the CERN accelerator departments for the excellent performance of the LHC and thank the technical and administrative staffs at CERN and at other CMS institutes for their contributions to the success of the CMS effort. In addition, we gratefully acknowledge the computing centers and personnel of the Worldwide LHC Computing Grid for delivering so effectively the computing infrastructure essential to our analyses. Finally, we acknowledge the enduring support for the construction and operation of the LHC and the CMS detector provided by the following funding agencies: BMWFW and FWF (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, and FAPESP (Brazil); MES (Bulgaria); CERN; CAS, MoST, and NSFC (China); COLCIENCIAS (Colombia); MSES and CSF (Croatia); RPF (Cyprus); SENESCYT (Ecuador); MoER, ERC IUT, and ERDF (Estonia); Academy of Finland, MEC, and HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG, and HGF (Germany); GSRT (Greece); OTKA and NIH (Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); MSIP and NRF (Republic of Korea); LAS (Lithuania); MOE and UM (Malaysia); BUAP, CINVESTAV, CONACYT, LNS, SEP, and UASLP-FAI (Mexico); MBIE (New Zealand); PAEC (Pakistan); MSHE and NSC (Poland); FCT (Portugal); JINR (Dubna); MON, RosAtom, RAS, RFBR and RAEP (Russia); MESTD (Serbia); SEIDI, CPAN, PCTI and FEDER (Spain); Swiss Funding Agencies (Switzerland); MST (Taipei); ThEPCenter, IPST, STAR, and NSTDA (Thailand); TUBITAK and TAEK (Turkey); NASU and SFFR (Ukraine); STFC (United Kingdom); DOE and NSF (USA). Individuals have received support from the Marie-Curie program and the European Research Council and Horizon 2020 Grant, contract No. 675440 (European Union); the Leventis Foundation; the A. P. Sloan Foundation; the Alexander von Humboldt Foundation; the Belgian Federal Science Policy Office; the Fonds pour la Formation à la Recherche dans l’Industrie et dans l’Agriculture (FRIA-Belgium); the Agentschap voor Innovatie door Wetenschap en Technologie (IWT-Belgium); the Ministry of Education, Youth and Sports (MEYS) of the Czech Republic; the Council of Science and Industrial Research, India; the HOMING PLUS program of the Foundation for Polish Science, cofinanced from European Union, Regional Development Fund, the Mobility Plus program of the Ministry of Science and Higher Education, the National Science Center (Poland), contracts Harmonia 2014/14/M/ST2/00428, Opus 2014/13/B/ST2/02543, 2014/15/B/ST2/03998, and 2015/19/B/ST2/02861, Sonata-bis 2012/07/E/ST2/01406; the National Priorities Research Program by Qatar National Research Fund; the Programa Clarín-COFUND del Principado de Asturias; the Thalis and Aristeia programs cofinanced by EU-ESF and the Greek NSRF; the Rachadapisek Sompot Fund for Postdoctoral Fellowship, Chulalongkorn University and the Chulalongkorn Academic into Its 2nd Century Project Advancement Project (Thailand); and the Welch Foundation, contract C-1845.

.9 The CMS Collaboration

**Yerevan Physics Institute, Yerevan, Armenia

** A.M. Sirunyan, A. Tumasyan \cmsinstskip**Institut für Hochenergiephysik, Wien, Austria

** W. Adam, E. Asilar, T. Bergauer, J. Brandstetter, E. Brondolin, M. Dragicevic, J. Erö, M. Flechl, M. Friedl, R. Frühwirth\cmsAuthorMark1, V.M. Ghete, N. Hörmann, J. Hrubec, M. Jeitler\cmsAuthorMark1, A. König, I. Krätschmer, D. Liko, T. Matsushita, I. Mikulec, D. Rabady, N. Rad, H. Rohringer, J. Schieck\cmsAuthorMark1, J. Strauss, W. Waltenberger, C.-E. Wulz\cmsAuthorMark1 \cmsinstskip**Institute for Nuclear Problems, Minsk, Belarus

** V. Chekhovsky, V. Mossolov, J. Suarez Gonzalez \cmsinstskip**National Centre for Particle and High Energy Physics, Minsk, Belarus

** N. Shumeiko \cmsinstskip**Universiteit Antwerpen, Antwerpen, Belgium

** S. Alderweireldt, E.A. De Wolf, X. Janssen, J. Lauwers, M. Van De Klundert, H. Van Haevermaet, P. Van Mechelen, N. Van Remortel, A. Van Spilbeeck \cmsinstskip**Vrije Universiteit Brussel, Brussel, Belgium

** S. Abu Zeid, F. Blekman, J. D’Hondt, I. De Bruyn, J. De Clercq, K. Deroover, S. Lowette, S. Moortgat, L. Moreels, A. Olbrechts, Q. Python, K. Skovpen, S. Tavernier, W. Van Doninck, P. Van Mulders, I. Van Parijs \cmsinstskip**Université Libre de Bruxelles, Bruxelles, Belgium

** H. Brun, B. Clerbaux, G. De Lentdecker, H. Delannoy, G. Fasanella, L. Favart, R. Goldouzian, A. Grebenyuk, G. Karapostoli, T. Lenzi, J. Luetic, T. Maerschalk, A. Marinov, A. Randle-conde, T. Seva, C. Vander Velde, P. Vanlaer, D. Vannerom, R. Yonamine, F. Zenoni, F. Zhang\cmsAuthorMark2 \cmsinstskip**Ghent University, Ghent, Belgium

** A. Cimmino, T. Cornelis, D. Dobur, A. Fagot, M. Gul, I. Khvastunov, D. Poyraz, S. Salva, R. Schöfbeck, M. Tytgat, W. Van Driessche, W. Verbeke, N. Zaganidis \cmsinstskip**Université Catholique de Louvain, Louvain-la-Neuve, Belgium

** H. Bakhshiansohi, O. Bondu, S. Brochet, G. Bruno, A. Caudron, S. De Visscher, C. Delaere, M. Delcourt, B. Francois, A. Giammanco, A. Jafari, M. Komm, G. Krintiras, V. Lemaitre, A. Magitteri, A. Mertens, M. Musich, K. Piotrzkowski, L. Quertenmont, M. Vidal Marono, S. Wertz \cmsinstskip**Université de Mons, Mons, Belgium

** N. Beliy \cmsinstskip**Centro Brasileiro de Pesquisas Fisicas, Rio de Janeiro, Brazil

** W.L. Aldá Júnior, F.L. Alves, G.A. Alves, L. Brito, C. Hensel, A. Moraes, M.E. Pol, P. Rebello Teles \cmsinstskip**Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brazil

** E. Belchior Batista Das Chagas, W. Carvalho, J. Chinellato\cmsAuthorMark3, A. Custódio, E.M. Da Costa, G.G. Da Silveira\cmsAuthorMark4, D. De Jesus Damiao, S. Fonseca De Souza, L.M. Huertas Guativa, H. Malbouisson, C. Mora Herrera, L. Mundim, H. Nogima, A. Santoro, A. Sznajder, E.J. Tonelli Manganote\cmsAuthorMark3, F. Torres Da Silva De Araujo, A. Vilela Pereira \cmsinstskip**Universidade Estadual Paulista a,  Universidade Federal do ABC b,  São Paulo, Brazil

** S. Ahujaa, C.A. Bernardesa, T.R. Fernandez Perez Tomeia, E.M. Gregoresb, P.G. Mercadanteb, C.S. Moona, S.F. Novaesa, Sandra S. Padulaa, D. Romero Abadb, J.C. Ruiz Vargasa \cmsinstskip**Institute for Nuclear Research and Nuclear Energy, Sofia, Bulgaria

** A. Aleksandrov, R. Hadjiiska, P. Iaydjiev, M. Rodozov, S. Stoykova, G. Sultanov, M. Vutova \cmsinstskip**University of Sofia, Sofia, Bulgaria

** A. Dimitrov, I. Glushkov, L. Litov, B. Pavlov, P. Petkov \cmsinstskip**Beihang University, Beijing, China

** W. Fang\cmsAuthorMark5, X. Gao\cmsAuthorMark5 \cmsinstskip**Institute of High Energy Physics, Beijing, China

** M. Ahmad, J.G. Bian, G.M. Chen, H.S. Chen, M. Chen, Y. Chen, C.H. Jiang, D. Leggat, Z. Liu, F. Romeo, S.M. Shaheen, A. Spiezia, J. Tao, C. Wang, Z. Wang, E. Yazgan, H. Zhang, J. Zhao \cmsinstskip**State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing, China

** Y. Ban, G. Chen, Q. Li, S. Liu, Y. Mao, S.J. Qian, D. Wang, Z. Xu \cmsinstskip**Universidad de Los Andes, Bogota, Colombia

** C. Avila, A. Cabrera, L.F. Chaparro Sierra, C. Florez, C.F. González Hernández, J.D. Ruiz Alvarez \cmsinstskip**University of Split, Faculty of Electrical Engineering, Mechanical Engineering and Naval Architecture, Split, Croatia

** N. Godinovic, D. Lelas, I. Puljak, P.M. Ribeiro Cipriano, T. Sculac \cmsinstskip**University of Split, Faculty of Science, Split, Croatia

** Z. Antunovic, M. Kovac \cmsinstskip**Institute Rudjer Boskovic, Zagreb, Croatia

** V. Brigljevic, D. Ferencek, K. Kadija, B. Mesic, T. Susa \cmsinstskip**University of Cyprus, Nicosia, Cyprus

** M.W. Ather, A. Attikis, G. Mavromanolakis, J. Mousa, C. Nicolaou, F. Ptochos, P.A. Razis, H. Rykaczewski \cmsinstskip**Charles University, Prague, Czech Republic

** M. Finger\cmsAuthorMark6, M. Finger Jr.\cmsAuthorMark6 \cmsinstskip**Universidad San Francisco de Quito, Quito, Ecuador

** E. Carrera Jarrin \cmsinstskip**Academy of Scientific Research and Technology of the Arab Republic of Egypt, Egyptian Network of High Energy Physics, Cairo, Egypt

** A.A. Abdelalim\cmsAuthorMark7*,\cmsAuthorMark8, Y. Mohammed\cmsAuthorMark9, E. Salama\cmsAuthorMark10,*\cmsAuthorMark11 \cmsinstskip**National Institute of Chemical Physics and Biophysics, Tallinn, Estonia

** R.K. Dewanjee, M. Kadastik, L. Perrini, M. Raidal, A. Tiko, C. Veelken \cmsinstskip**Department of Physics, University of Helsinki, Helsinki, Finland

** P. Eerola, J. Pekkanen, M. Voutilainen \cmsinstskip**Helsinki Institute of Physics, Helsinki, Finland

** J. Härkönen, T. Järvinen, V. Karimäki, R. Kinnunen, T. Lampén, K. Lassila-Perini, S. Lehti, T. Lindén, P. Luukka, E. Tuominen, J. Tuominiemi, E. Tuovinen \cmsinstskip**Lappeenranta University of Technology, Lappeenranta, Finland

** J. Talvitie, T. Tuuva \cmsinstskip**IRFU, CEA, Université Paris-Saclay, Gif-sur-Yvette, France

** M. Besancon, F. Couderc, M. Dejardin, D. Denegri, J.L. Faure, F. Ferri, S. Ganjour, S. Ghosh, A. Givernaud, P. Gras, G. Hamel de Monchenault, P. Jarry, I. Kucher, E. Locci, M. Machet, J. Malcles, J. Rander, A. Rosowsky, M.Ö. Sahin, M. Titov \cmsinstskip**Laboratoire Leprince-Ringuet, Ecole polytechnique, CNRS/IN2P3, Université Paris-Saclay, Palaiseau, France

** A. Abdulsalam, I. Antropov, S. Baffioni, F. Beaudette, P. Busson, L. Cadamuro, E. Chapon, C. Charlot, O. Davignon, R. Granier de Cassagnac, M. Jo, S. Lisniak, A. Lobanov, P. Miné, M. Nguyen, C. Ochando, G. Ortona, P. Paganini, P. Pigard, S. Regnard, R. Salerno, Y. Sirois, A.G. Stahl Leiton, T. Strebler, Y. Yilmaz, A. Zabi, A. Zghiche \cmsinstskip**Université de Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg, France

** J.-L. Agram\cmsAuthorMark12, J. Andrea, D. Bloch, J.-M. Brom, M. Buttignol, E.C. Chabert, N. Chanon, C. Collard, E. Conte\cmsAuthorMark12, X. Coubez, J.-C. Fontaine\cmsAuthorMark12, D. Gelé, U. Goerlach, A.-C. Le Bihan, P. Van Hove \cmsinstskip**Centre de Calcul de l’Institut National de Physique Nucleaire et de Physique des Particules, CNRS/IN2P3, Villeurbanne, France

** S. Gadrat \cmsinstskip**Université de Lyon, Université Claude Bernard Lyon 1,  CNRS-IN2P3, Institut de Physique Nucléaire de Lyon, Villeurbanne, France

** S. Beauceron, C. Bernet, G. Boudoul, R. Chierici, D. Contardo, B. Courbon, P. Depasse, H. El Mamouni, J. Fay, L. Finco, S. Gascon, M. Gouzevitch, G. Grenier, B. Ille, F. Lagarde, I.B. Laktineh, M. Lethuillier, L. Mirabito, A.L. Pequegnot, S. Perries, A. Popov\cmsAuthorMark13, V. Sordini, M. Vander Donckt, S. Viret \cmsinstskip**Georgian Technical University, Tbilisi, Georgia

** T. Toriashvili\cmsAuthorMark14 \cmsinstskip**Tbilisi State University, Tbilisi, Georgia

** D. Lomidze \cmsinstskip**RWTH Aachen University, I. Physikalisches Institut, Aachen, Germany

** C. Autermann, S. Beranek, L. Feld, M.K. Kiesel, K. Klein, M. Lipinski, M. Preuten, C. Schomakers, J. Schulz, T. Verlage \cmsinstskip**RWTH Aachen University, III. Physikalisches Institut A,  Aachen, Germany

** A. Albert, M. Brodski, E. Dietz-Laursonn, D. Duchardt, M. Endres, M. Erdmann, S. Erdweg, T. Esch, R. Fischer, A. Güth, M. Hamer, T. Hebbeker, C. Heidemann, K. Hoepfner, S. Knutzen, M. Merschmeyer, A. Meyer, P. Millet, S. Mukherjee, M. Olschewski, K. Padeken, T. Pook, M. Radziej, H. Reithler, M. Rieger, F. Scheuch, L. Sonnenschein, D. Teyssier, S. Thüer \cmsinstskip**RWTH Aachen University, III. Physikalisches Institut B,  Aachen, Germany

** G. Flügge, B. Kargoll, T. Kress, A. Künsken, J. Lingemann, T. Müller, A. Nehrkorn, A. Nowack, C. Pistone, O. Pooth, A. Stahl\cmsAuthorMark15 \cmsinstskip**Deutsches Elektronen-Synchrotron, Hamburg, Germany

** M. Aldaya Martin, T. Arndt, C. Asawatangtrakuldee, K. Beernaert, O. Behnke, U. Behrens, A.A. Bin Anuar, K. Borras\cmsAuthorMark16, V. Botta, A. Campbell, P. Connor, C. Contreras-Campana, F. Costanza, C. Diez Pardos, G. Eckerlin, D. Eckstein, T. Eichhorn, E. Eren, E. Gallo\cmsAuthorMark17, J. Garay Garcia, A. Geiser, A. Gizhko, J.M. Grados Luyando, A. Grohsjean, P. Gunnellini, A. Harb, J. Hauk, M. Hempel\cmsAuthorMark18, H. Jung, A. Kalogeropoulos, M. Kasemann, J. Keaveney, C. Kleinwort, I. Korol, D. Krücker, W. Lange, A. Lelek, T. Lenz, J. Leonard, K. Lipka, W. Lohmann\cmsAuthorMark18, R. Mankel, I.-A. Melzer-Pellmann, A.B. Meyer, G. Mittag, J. Mnich, A. Mussgiller, E. Ntomari, D. Pitzl, R. Placakyte, A. Raspereza, B. Roland, M. Savitskyi, P. Saxena, R. Shevchenko, S. Spannagel, N. Stefaniuk, G.P. Van Onsem, R. Walsh, Y. Wen, K. Wichmann, C. Wissing \cmsinstskip**University of Hamburg, Hamburg, Germany

** S. Bein, V. Blobel, M. Centis Vignali, A.R. Draeger, T. Dreyer, E. Garutti, D. Gonzalez, J. Haller, M. Hoffmann, A. Junkes, R. Klanner, R. Kogler, N. Kovalchuk, S. Kurz, T. Lapsien, I. Marchesini, D. Marconi, M. Meyer, M. Niedziela, D. Nowatschin, F. Pantaleo\cmsAuthorMark15, T. Peiffer, A. Perieanu, C. Scharf, P. Schleper, A. Schmidt, S. Schumann, J. Schwandt, J. Sonneveld, H. Stadie, G. Steinbrück, F.M. Stober, M. Stöver, H. Tholen, D. Troendle, E. Usai, L. Vanelderen, A. Vanhoefer, B. Vormwald \cmsinstskip**Institut für Experimentelle Kernphysik, Karlsruhe, Germany

** M. Akbiyik, C. Barth, S. Baur, C. Baus, J. Berger, E. Butz, R. Caspart, T. Chwalek, F. Colombo, W. De Boer, A. Dierlamm, B. Freund, R. Friese, M. Giffels, A. Gilbert, D. Haitz, F. Hartmann\cmsAuthorMark15, S.M. Heindl, U. Husemann, F. Kassel\cmsAuthorMark15, S. Kudella, H. Mildner, M.U. Mozer, Th. Müller, M. Plagge, G. Quast, K. Rabbertz, M. Schröder, I. Shvetsov, G. Sieber, H.J. Simonis, R. Ulrich, S. Wayand, M. Weber, T. Weiler, S. Williamson, C. Wöhrmann, R. Wolf \cmsinstskip**Institute of Nuclear and Particle Physics (INPP),  NCSR Demokritos, Aghia Paraskevi, Greece

** G. Anagnostou, G. Daskalakis, T. Geralis, V.A. Giakoumopoulou, A. Kyriakis, D. Loukas, I. Topsis-Giotis \cmsinstskip**National and Kapodistrian University of Athens, Athens, Greece

** S. Kesisoglou, A. Panagiotou, N. Saoulidou \cmsinstskip**University of Ioánnina, Ioánnina, Greece

** I. Evangelou, G. Flouris, C. Foudas, P. Kokkas, N. Manthos, I. Papadopoulos, E. Paradas, J. Strologas, F.A. Triantis \cmsinstskip**MTA-ELTE Lendület CMS Particle and Nuclear Physics Group, Eötvös Loránd University, Budapest, Hungary

** M. Csanad, N. Filipovic, G. Pasztor \cmsinstskip**Wigner Research Centre for Physics, Budapest, Hungary

** G. Bencze, C. Hajdu, D. Horvath\cmsAuthorMark19, F. Sikler, V. Veszpremi, G. Vesztergombi\cmsAuthorMark20, A.J. Zsigmond \cmsinstskip**Institute of Nuclear Research ATOMKI, Debrecen, Hungary

** N. Beni, S. Czellar, J. Karancsi\cmsAuthorMark21, A. Makovec, J. Molnar, Z. Szillasi \cmsinstskip**Institute of Physics, University of Debrecen, Debrecen, Hungary

** M. Bartók\cmsAuthorMark20, P. Raics, Z.L. Trocsanyi, B. Ujvari \cmsinstskip**Indian Institute of Science (IISc),  Bangalore, India

** S. Choudhury, J.R. Komaragiri \cmsinstskip**National Institute of Science Education and Research, Bhubaneswar, India

** S. Bahinipati\cmsAuthorMark22, S. Bhowmik, P. Mal, K. Mandal, A. Nayak\cmsAuthorMark23, D.K. Sahoo\cmsAuthorMark22, N. Sahoo, S.K. Swain \cmsinstskip**Panjab University, Chandigarh, India

** S. Bansal, S.B. Beri, V. Bhatnagar, U. Bhawandeep, R. Chawla, N. Dhingra, A.K. Kalsi, A. Kaur, M. Kaur, R. Kumar, P. Kumari, A. Mehta, M. Mittal, J.B. Singh, G. Walia \cmsinstskip**University of Delhi, Delhi, India

** Ashok Kumar, Aashaq Shah, A. Bhardwaj, S. Chauhan, B.C. Choudhary, R.B. Garg, S. Keshri, S. Malhotra, M. Naimuddin, K. Ranjan, R. Sharma, V. Sharma \cmsinstskip**Saha Institute of Nuclear Physics, HBNI, Kolkata, India

** R. Bhattacharya, S. Bhattacharya, S. Dey, S. Dutt, S. Dutta, S. Ghosh, N. Majumdar, A. Modak, K. Mondal, S. Mukhopadhyay, S. Nandan, A. Purohit, A. Roy, D. Roy, S. Roy Chowdhury, S. Sarkar, M. Sharan, S. Thakur \cmsinstskip**Indian Institute of Technology Madras, Madras, India

** P.K. Behera \cmsinstskip**Bhabha Atomic Research Centre, Mumbai, India

** R. Chudasama, D. Dutta, V. Jha, V. Kumar, A.K. Mohanty\cmsAuthorMark15, P.K. Netrakanti, L.M. Pant, P. Shukla, A. Topkar \cmsinstskip**Tata Institute of Fundamental Research-A, Mumbai, India

** T. Aziz, S. Dugad, B. Mahakud, S. Mitra, G.B. Mohanty, B. Parida, N. Sur, B. Sutar \cmsinstskip**Tata Institute of Fundamental Research-B, Mumbai, India

** S. Banerjee, S. Bhattacharya, S. Chatterjee, P. Das, M. Guchait, Sa. Jain, S. Kumar, M. Maity\cmsAuthorMark24, G. Majumder, K. Mazumdar, T. Sarkar\cmsAuthorMark24, N. Wickramage\cmsAuthorMark25 \cmsinstskip**Indian Institute of Science Education and Research (IISER),  Pune, India

** S. Chauhan, S. Dube, V. Hegde, A. Kapoor, K. Kothekar, S. Pandey, A. Rane, S. Sharma \cmsinstskip**Institute for Research in Fundamental Sciences (IPM),  Tehran, Iran

** S. Chenarani\cmsAuthorMark26, E. Eskandari Tadavani, S.M. Etesami\cmsAuthorMark26, M. Khakzad, M. Mohammadi Najafabadi, M. Naseri, S. Paktinat Mehdiabadi\cmsAuthorMark27, F. Rezaei Hosseinabadi, B. Safarzadeh\cmsAuthorMark28, M. Zeinali \cmsinstskip**University College Dublin, Dublin, Ireland

** M. Felcini, M. Grunewald \cmsinstskip**INFN Sezione di Bari a, Università di Bari b, Politecnico di Bari c,  Bari, Italy

** M. Abbresciaa**,b, C. Calabriaa**,b, C. Caputoa**,b, A. Colaleoa, D. Creanzaa**,c, L. Cristellaa**,b, N. De Filippisa**,c, M. De Palmaa**,b, L. Fiorea, G. Iasellia**,c, G. Maggia**,c, M. Maggia, G. Minielloa**,b, S. Mya**,b, S. Nuzzoa**,b, A. Pompilia**,b, G. Pugliesea**,c, R. Radognaa**,b, A. Ranieria, G. Selvaggia**,b, A. Sharmaa, L. Silvestrisa**,\cmsAuthorMark15, R. Vendittia, P. Verwilligena \cmsinstskip**INFN Sezione di Bologna a, Università di Bologna b,  Bologna, Italy

** G. Abbiendia, C. Battilana, D. Bonacorsia**,b, S. Braibant-Giacomellia**,b, L. Brigliadoria**,b, R. Campaninia**,b, P. Capiluppia**,b, A. Castroa**,b, F.R. Cavalloa, S.S. Chhibraa**,b, M. Cuffiania**,b, G.M. Dallavallea, F. Fabbria, A. Fanfania**,b, D. Fasanellaa**,b, P. Giacomellia, L. Guiduccia**,b, S. Marcellinia, G. Masettia, F.L. Navarriaa**,b, A. Perrottaa, A.M. Rossia**,b, T. Rovellia**,b, G.P. Sirolia**,b, N. Tosia**,b,\cmsAuthorMark15 \cmsinstskip**INFN Sezione di Catania a, Università di Catania b,  Catania, Italy

** S. Albergoa**,b, S. Costaa**,b, A. Di Mattiaa, F. Giordano*a**,b, R. Potenzaa**,b, A. Tricomia**,b, C. Tuvea**,*b \cmsinstskip**INFN Sezione di Firenze a, Università di Firenze b,  Firenze, Italy

** G. Barbaglia, K. Chatterjeea**,b, V. Ciullia**,b, C. Civininia, R. D’Alessandroa**,b, E. Focardia**,b, P. Lenzia**,b, M. Meschinia, S. Paolettia, L. Russoa**,\cmsAuthorMark29, G. Sguazzonia, D. Stroma, L. Viliania**,b,\cmsAuthorMark15 \cmsinstskip**INFN Laboratori Nazionali di Frascati, Frascati, Italy

** L. Benussi, S. Bianco, F. Fabbri, D. Piccolo, F. Primavera\cmsAuthorMark15 \cmsinstskip**INFN Sezione di Genova a, Università di Genova b,  Genova, Italy

** V. Calvellia**,b, F. Ferroa, E. Robuttia, S. Tosi*a**,*b \cmsinstskip**INFN Sezione di Milano-Bicocca a, Università di Milano-Bicocca b,  Milano, Italy

** L. Brianzaa**,b,\cmsAuthorMark15, F. Brivioa**,b, V. Ciriolo, M.E. Dinardoa**,b, S. Fiorendia**,b,\cmsAuthorMark15, S. Gennaia, A. Ghezzia**,b, P. Govonia**,b, M. Malbertia**,b, S. Malvezzia, R.A. Manzonia**,b, D. Menascea, L. Moronia, M. Paganonia**,b, K. Pauwels, D. Pedrinia, S. Pigazzini*a**,b, S. Ragazzia**,b, T. Tabarelli de Fatisa**,*b \cmsinstskip**INFN Sezione di Napoli a, Università di Napoli ’Federico II’ b, Napoli, Italy, Università della Basilicata c, Potenza, Italy, Università G. Marconi d, Roma, Italy

** S. Buontempoa, N. Cavalloa**,c, S. Di Guidaa**,d,\cmsAuthorMark15, M. Espositoa**,b, F. Fabozzia**,c, F. Fiengaa**,b, A.O.M. Iorioa**,b, W.A. Khana, G. Lanzaa, L. Listaa, S. Meolaa**,d,\cmsAuthorMark15, P. Paoluccia**,\cmsAuthorMark15, C. Sciaccaa**,b, F. Thyssena \cmsinstskip**INFN Sezione di Padova a, Università di Padova b, Padova, Italy, Università di Trento c, Trento, Italy

** P. Azzia**,\cmsAuthorMark15, N. Bacchettaa, L. Benatoa**,b, A. Bolettia**,b, R. Carlina**,b, A. Carvalho Antunes De Oliveiraa**,b, P. Checchiaa, M. Dall’Ossoa**,b, P. De Castro Manzanoa, T. Dorigoa, U. Gasparinia**,b, A. Gozzelinoa, S. Lacapraraa, M. Margonia**,b, A.T. Meneguzzoa**,b, M. Michelottoa, F. Montecassianoa, M. Passaseoa, N. Pozzobona**,b, P. Ronchesea**,b, R. Rossina**,b, F. Simonettoa**,b, E. Torassaa, M. Zanetti*a**,b, P. Zottoa**,b, G. Zumerlea**,*b \cmsinstskip**INFN Sezione di Pavia a, Università di Pavia b,  Pavia, Italy

** A. Braghieria, F. Fallavollitaa**,b, A. Magnania**,b, P. Montagnaa**,b, S.P. Rattia**,b, V. Rea, M. Ressegotti, C. Riccardia**,b, P. Salvinia, I. Vai*a**,b, P. Vituloa**,*b \cmsinstskip**INFN Sezione di Perugia a, Università di Perugia b,  Perugia, Italy

** L. Alunni Solestizia**,b, G.M. Bileia, D. Ciangottinia**,b, L. Fanòa**,b, P. Laricciaa**,b, R. Leonardia**,b, G. Mantovania**,b, V. Mariania**,b, M. Menichellia, A. Sahaa, A. Santocchia*a**,*b, D. Spiga \cmsinstskip**INFN Sezione di Pisa a, Università di Pisa b, Scuola Normale Superiore di Pisa c,  Pisa, Italy

** K. Androsova, P. Azzurria**,\cmsAuthorMark15, G. Bagliesia, J. Bernardinia, T. Boccalia, L. Borrello, R. Castaldia, M.A. Cioccia**,b, R. Dell’Orsoa, G. Fedia, A. Giassia, M.T. Grippoa**,\cmsAuthorMark29, F. Ligabuea**,c, T. Lomtadzea, L. Martinia**,b, A. Messineoa**,b, F. Pallaa, A. Rizzia**,b, A. Savoy-Navarroa**,\cmsAuthorMark30, P. Spagnoloa, R. Tenchinia, G. Tonellia**,b, A. Venturia, P.G. Verdinia \cmsinstskip**INFN Sezione di Roma a, Sapienza Università di Roma b,  Rome, Italy

** L. Baronea**,b, F. Cavallaria, M. Cipriania**,b, D. Del Rea**,b,\cmsAuthorMark15, M. Diemoza, S. Gellia**,b, E. Longoa**,b, F. Margarolia**,b, B. Marzocchia**,b, P. Meridiania, G. Organtinia**,b, R. Paramattia**,b, F. Preiatoa**,b, S. Rahatloua**,b, C. Rovellia, F. Santanastasio*a**,*b \cmsinstskip**INFN Sezione di Torino a, Università di Torino b, Torino, Italy, Università del Piemonte Orientale c, Novara, Italy

** N. Amapanea**,b, R. Arcidiaconoa**,c,\cmsAuthorMark15, S. Argiroa**,b, M. Arneodoa**,c, N. Bartosika, R. Bellana**,b, C. Biinoa, N. Cartigliaa, F. Cennaa**,b, M. Costaa**,b, R. Covarellia**,b, A. Deganoa**,b, N. Demariaa, B. Kiania**,b, C. Mariottia, S. Masellia, E. Migliorea**,b, V. Monacoa**,b, E. Monteila**,b, M. Montenoa, M.M. Obertinoa**,b, L. Pachera**,b, N. Pastronea, M. Pelliccionia, G.L. Pinna Angionia**,b, F. Raveraa**,b, A. Romeroa**,b, M. Ruspaa**,c, R. Sacchia**,b, K. Shchelinaa**,b, V. Solaa, A. Solanoa**,b, A. Staianoa, P. Traczyk*a**,*b \cmsinstskip**INFN Sezione di Trieste a, Università di Trieste b,  Trieste, Italy

** S. Belfortea, M. Casarsaa, F. Cossuttia, G. Della Riccaa**,b, A. Zanettia \cmsinstskip**Kyungpook National University, Daegu, Korea

** D.H. Kim, G.N. Kim, M.S. Kim, J. Lee, S. Lee, S.W. Lee, Y.D. Oh, S. Sekmen, D.C. Son, Y.C. Yang \cmsinstskip**Chonbuk National University, Jeonju, Korea

** A. Lee \cmsinstskip**Chonnam National University, Institute for Universe and Elementary Particles, Kwangju, Korea

** H. Kim, D.H. Moon \cmsinstskip**Hanyang University, Seoul, Korea

** J.A. Brochero Cifuentes, J. Goh, T.J. Kim \cmsinstskip**Korea University, Seoul, Korea

** S. Cho, S. Choi, Y. Go, D. Gyun, S. Ha, B. Hong, Y. Jo, Y. Kim, K. Lee, K.S. Lee, S. Lee, J. Lim, S.K. Park, Y. Roh \cmsinstskip**Seoul National University, Seoul, Korea

** J. Almond, J. Kim, H. Lee, S.B. Oh, B.C. Radburn-Smith, S.h. Seo, U.K. Yang, H.D. Yoo, G.B. Yu \cmsinstskip**University of Seoul, Seoul, Korea

** M. Choi, H. Kim, J.H. Kim, J.S.H. Lee, I.C. Park, G. Ryu \cmsinstskip**Sungkyunkwan University, Suwon, Korea

** Y. Choi, C. Hwang, J. Lee, I. Yu \cmsinstskip**Vilnius University, Vilnius, Lithuania

** V. Dudenas, A. Juodagalvis, J. Vaitkus \cmsinstskip**National Centre for Particle Physics, Universiti Malaya, Kuala Lumpur, Malaysia

** I. Ahmed, Z.A. Ibrahim, M.A.B. Md Ali\cmsAuthorMark31, F. Mohamad Idris\cmsAuthorMark32, W.A.T. Wan Abdullah, M.N. Yusli, Z. Zolkapli \cmsinstskip**Centro de Investigacion y de Estudios Avanzados del IPN, Mexico City, Mexico

** H. Castilla-Valdez, E. De La Cruz-Burelo, I. Heredia-De La Cruz\cmsAuthorMark33, R. Lopez-Fernandez, J. Mejia Guisao, A. Sanchez-Hernandez \cmsinstskip**Universidad Iberoamericana, Mexico City, Mexico

** S. Carrillo Moreno, C. Oropeza Barrera, F. Vazquez Valencia \cmsinstskip**Benemerita Universidad Autonoma de Puebla, Puebla, Mexico

** I. Pedraza, H.A. Salazar Ibarguen, C. Uribe Estrada \cmsinstskip**Universidad Autónoma de San Luis Potosí,  San Luis Potosí,  Mexico

** A. Morelos Pineda \cmsinstskip**University of Auckland, Auckland, New Zealand

** D. Krofcheck \cmsinstskip**University of Canterbury, Christchurch, New Zealand

** P.H. Butler \cmsinstskip**National Centre for Physics, Quaid-I-Azam University, Islamabad, Pakistan

** A. Ahmad, M. Ahmad, Q. Hassan, H.R. Hoorani, A. Saddique, M.A. Shah, M. Shoaib, M. Waqas \cmsinstskip**National Centre for Nuclear Research, Swierk, Poland

** H. Bialkowska, M. Bluj, B. Boimska, T. Frueboes, M. Górski, M. Kazana, K. Nawrocki, K. Romanowska-Rybinska, M. Szleper, P. Zalewski \cmsinstskip**Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Warsaw, Poland

** K. Bunkowski, A. Byszuk\cmsAuthorMark34, K. Doroba, A. Kalinowski, M. Konecki, J. Krolikowski, M. Misiura, M. Olszewski, A. Pyskir, M. Walczak \cmsinstskip**Laboratório de Instrumentação e Física Experimental de Partículas, Lisboa, Portugal

** P. Bargassa, C. Beirão Da Cruz E Silva, B. Calpas, A. Di Francesco, P. Faccioli, M. Gallinaro, J. Hollar, N. Leonardo, L. Lloret Iglesias, M.V. Nemallapudi, J. Seixas, O. Toldaiev, D. Vadruccio, J. Varela \cmsinstskip**Joint Institute for Nuclear Research, Dubna, Russia

** S. Afanasiev, P. Bunin, M. Gavrilenko, I. Golutvin, I. Gorbunov, A. Kamenev, V. Karjavin, A. Lanev, A. Malakhov, V. Matveev\cmsAuthorMark35*,*\cmsAuthorMark36, V. Palichik, V. Perelygin, S. Shmatov, S. Shulha, N. Skatchkov, V. Smirnov, N. Voytishin, A. Zarubin \cmsinstskip**Petersburg Nuclear Physics Institute, Gatchina (St. Petersburg),  Russia

** Y. Ivanov, V. Kim\cmsAuthorMark37, E. Kuznetsova\cmsAuthorMark38, P. Levchenko, V. Murzin, V. Oreshkin, I. Smirnov, V. Sulimov, L. Uvarov, S. Vavilov, A. Vorobyev \cmsinstskip**Institute for Nuclear Research, Moscow, Russia

** Yu. Andreev, A. Dermenev, S. Gninenko, N. Golubev, A. Karneyeu, M. Kirsanov, N. Krasnikov, A. Pashenkov, D. Tlisov, A. Toropin \cmsinstskip**Institute for Theoretical and Experimental Physics, Moscow, Russia

** V. Epshteyn, V. Gavrilov, N. Lychkovskaya, V. Popov, I. Pozdnyakov, G. Safronov, A. Spiridonov, M. Toms, E. Vlasov, A. Zhokin \cmsinstskip**Moscow Institute of Physics and Technology, Moscow, Russia

** T. Aushev, A. Bylinkin\cmsAuthorMark36 \cmsinstskip**National Research Nuclear University ’Moscow Engineering Physics Institute’ (MEPhI),  Moscow, Russia

** M. Chadeeva\cmsAuthorMark39, S. Polikarpov, V. Rusinov \cmsinstskip**P.N. Lebedev Physical Institute, Moscow, Russia

** V. Andreev, M. Azarkin\cmsAuthorMark36, I. Dremin\cmsAuthorMark36, M. Kirakosyan, A. Terkulov \cmsinstskip**Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, Moscow, Russia

** A. Baskakov, A. Belyaev, E. Boos, V. Bunichev, M. Dubinin\cmsAuthorMark40, L. Dudko, V. Klyukhin, O. Kodolova, N. Korneeva, I. Lokhtin, I. Miagkov, S. Obraztsov, M. Perfilov, V. Savrin, P. Volkov \cmsinstskip**Novosibirsk State University (NSU),  Novosibirsk, Russia

** V. Blinov\cmsAuthorMark41, Y.Skovpen\cmsAuthorMark41, D. Shtol\cmsAuthorMark41 \cmsinstskip**State Research Center of Russian Federation, Institute for High Energy Physics, Protvino, Russia

** I. Azhgirey, I. Bayshev, S. Bitioukov, D. Elumakhov, V. Kachanov, A. Kalinin, D. Konstantinov, V. Krychkine, V. Petrov, R. Ryutin, A. Sobol, S. Troshin, N. Tyurin, A. Uzunian, A. Volkov \cmsinstskip**University of Belgrade, Faculty of Physics and Vinca Institute of Nuclear Sciences, Belgrade, Serbia

** P. Adzic\cmsAuthorMark42, P. Cirkovic, D. Devetak, M. Dordevic, J. Milosevic, V. Rekovic \cmsinstskip**Centro de Investigaciones Energéticas Medioambientales y Tecnológicas (CIEMAT),  Madrid, Spain

** J. Alcaraz Maestre, M. Barrio Luna, M. Cerrada, N. Colino, B. De La Cruz, A. Delgado Peris, A. Escalante Del Valle, C. Fernandez Bedoya, J.P. Fernández Ramos, J. Flix, M.C. Fouz, P. Garcia-Abia, O. Gonzalez Lopez, S. Goy Lopez, J.M. Hernandez, M.I. Josa, A. Pérez-Calero Yzquierdo, J. Puerta Pelayo, A. Quintario Olmeda, I. Redondo, L. Romero, M.S. Soares \cmsinstskip**Universidad Autónoma de Madrid, Madrid, Spain

** J.F. de Trocóniz, M. Missiroli, D. Moran \cmsinstskip**Universidad de Oviedo, Oviedo, Spain

** J. Cuevas, C. Erice, J. Fernandez Menendez, I. Gonzalez Caballero, J.R. González Fernández, E. Palencia Cortezon, S. Sanchez Cruz, I. Suárez Andrés, P. Vischia, J.M. Vizan Garcia \cmsinstskip**Instituto de Física de Cantabria (IFCA),  CSIC-Universidad de Cantabria, Santander, Spain

** I.J. Cabrillo, A. Calderon, B. Chazin Quero, E. Curras, M. Fernandez, J. Garcia-Ferrero, G. Gomez, A. Lopez Virto, J. Marco, C. Martinez Rivero, F. Matorras, J. Piedra Gomez, T. Rodrigo, A. Ruiz-Jimeno, L. Scodellaro, N. Trevisani, I. Vila, R. Vilar Cortabitarte \cmsinstskip**CERN, European Organization for Nuclear Research, Geneva, Switzerland

** D. Abbaneo, E. Auffray, P. Baillon, A.H. Ball, D. Barney, M. Bianco, P. Bloch, A. Bocci, C. Botta, T. Camporesi, R. Castello, M. Cepeda, G. Cerminara, Y. Chen, D. d’Enterria, A. Dabrowski, V. Daponte, A. David, M. De Gruttola, A. De Roeck, E. Di Marco\cmsAuthorMark43, M. Dobson, B. Dorney, T. du Pree, M. Dünser, N. Dupont, A. Elliott-Peisert, P. Everaerts, G. Franzoni, J. Fulcher, W. Funk, D. Gigi, K. Gill, F. Glege, D. Gulhan, S. Gundacker, M. Guthoff, P. Harris, J. Hegeman, V. Innocente, P. Janot, O. Karacheban\cmsAuthorMark18, J. Kieseler, H. Kirschenmann, V. Knünz, A. Kornmayer\cmsAuthorMark15, M.J. Kortelainen, C. Lange, P. Lecoq, C. Lourenço, M.T. Lucchini, L. Malgeri, M. Mannelli, A. Martelli, F. Meijers, J.A. Merlin, S. Mersi, E. Meschi, P. Milenovic\cmsAuthorMark44, F. Moortgat, M. Mulders, H. Neugebauer, S. Orfanelli, L. Orsini, L. Pape, E. Perez, M. Peruzzi, A. Petrilli, G. Petrucciani, A. Pfeiffer, M. Pierini, A. Racz, T. Reis, G. Rolandi\cmsAuthorMark45, M. Rovere, H. Sakulin, J.B. Sauvan, C. Schäfer, C. Schwick, M. Seidel, A. Sharma, P. Silva, P. Sphicas\cmsAuthorMark46, J. Steggemann, M. Stoye, M. Tosi, D. Treille, A. Triossi, A. Tsirou, V. Veckalns\cmsAuthorMark47, G.I. Veres\cmsAuthorMark20, M. Verweij, N. Wardle, A. Zagozdzinska\cmsAuthorMark34, W.D. Zeuner \cmsinstskip**Paul Scherrer Institut, Villigen, Switzerland

** W. Bertl, K. Deiters, W. Erdmann, R. Horisberger, Q. Ingram, H.C. Kaestli, D. Kotlinski, U. Langenegger, T. Rohe, S.A. Wiederkehr \cmsinstskip**Institute for Particle Physics, ETH Zurich, Zurich, Switzerland

** F. Bachmair, L. Bäni, P. Berger, L. Bianchini, B. Casal, G. Dissertori, M. Dittmar, M. Donegà, C. Grab, C. Heidegger, D. Hits, J. Hoss, G. Kasieczka, T. Klijnsma, W. Lustermann, B. Mangano, M. Marionneau, P. Martinez Ruiz del Arbol, M. Masciovecchio, M.T. Meinhard, D. Meister, F. Micheli, P. Musella, F. Nessi-Tedaldi, F. Pandolfi, J. Pata, F. Pauss, G. Perrin, L. Perrozzi, M. Quittnat, M. Rossini, M. Schönenberger, A. Starodumov\cmsAuthorMark48, V.R. Tavolaro, K. Theofilatos, M.L. Vesterbacka Olsson, R. Wallny, D.H. Zhu \cmsinstskip**Universität Zürich, Zurich, Switzerland

** T.K. Aarrestad, C. Amsler\cmsAuthorMark49, L. Caminada, M.F. Canelli, A. De Cosa, S. Donato, C. Galloni, A. Hinzmann, T. Hreus, B. Kilminster, J. Ngadiuba, D. Pinna, G. Rauco, P. Robmann, D. Salerno, C. Seitz, Y. Yang, A. Zucchetta \cmsinstskip**National Central University, Chung-Li, Taiwan

** V. Candelise, T.H. Doan, Sh. Jain, R. Khurana, M. Konyushikhin, C.M. Kuo, W. Lin, A. Pozdnyakov, S.S. Yu \cmsinstskip**National Taiwan University (NTU),  Taipei, Taiwan

** Arun Kumar, P. Chang, Y.H. Chang, Y. Chao, K.F. Chen, P.H. Chen, F. Fiori, W.-S. Hou, Y. Hsiung, Y.F. Liu, R.-S. Lu, M. Miñano Moya, E. Paganis, A. Psallidas, J.f. Tsai \cmsinstskip**Chulalongkorn University, Faculty of Science, Department of Physics, Bangkok, Thailand

** B. Asavapibhop, K. Kovitanggoon, G. Singh, N. Srimanobhas \cmsinstskip**Cukurova University, Physics Department, Science and Art Faculty, Adana, Turkey

** A. Adiguzel, M.N. Bakirci\cmsAuthorMark50, F. Boran, S. Damarseckin, Z.S. Demiroglu, C. Dozen, E. Eskut, S. Girgis, G. Gokbulut, Y. Guler, I. Hos\cmsAuthorMark51, E.E. Kangal\cmsAuthorMark52, O. Kara, U. Kiminsu, M. Oglakci, G. Onengut\cmsAuthorMark53, K. Ozdemir\cmsAuthorMark54, S. Ozturk\cmsAuthorMark50, A. Polatoz, D. Sunar Cerci\cmsAuthorMark55, S. Turkcapar, I.S. Zorbakir, C. Zorbilmez \cmsinstskip**Middle East Technical University, Physics Department, Ankara, Turkey

** B. Bilin, G. Karapinar\cmsAuthorMark56, K. Ocalan\cmsAuthorMark57, M. Yalvac, M. Zeyrek \cmsinstskip**Bogazici University, Istanbul, Turkey

** E. Gülmez, M. Kaya\cmsAuthorMark58, O. Kaya\cmsAuthorMark59, E.A. Yetkin\cmsAuthorMark60 \cmsinstskip**Istanbul Technical University, Istanbul, Turkey

** A. Cakir, K. Cankocak \cmsinstskip**Institute for Scintillation Materials of National Academy of Science of Ukraine, Kharkov, Ukraine

** B. Grynyov \cmsinstskip**National Scientific Center, Kharkov Institute of Physics and Technology, Kharkov, Ukraine

** L. Levchuk, P. Sorokin \cmsinstskip**University of Bristol, Bristol, United Kingdom

** R. Aggleton, F. Ball, L. Beck, J.J. Brooke, D. Burns, E. Clement, D. Cussans, H. Flacher, J. Goldstein, M. Grimes, G.P. Heath, H.F. Heath, J. Jacob, L. Kreczko, C. Lucas, D.M. Newbold\cmsAuthorMark61, S. Paramesvaran, A. Poll, T. Sakuma, S. Seif El Nasr-storey, D. Smith, V.J. Smith \cmsinstskip**Rutherford Appleton Laboratory, Didcot, United Kingdom

** K.W. Bell, A. Belyaev\cmsAuthorMark62, C. Brew, R.M. Brown, L. Calligaris, D. Cieri, D.J.A. Cockerill, J.A. Coughlan, K. Harder, S. Harper, E. Olaiya, D. Petyt, C.H. Shepherd-Themistocleous, A. Thea, I.R. Tomalin, T. Williams \cmsinstskip**Imperial College, London, United Kingdom

** M. Baber, R. Bainbridge, O. Buchmuller, A. Bundock, S. Casasso, M. Citron, D. Colling, L. Corpe, P. Dauncey, G. Davies, A. De Wit, M. Della Negra, R. Di Maria, P. Dunne, A. Elwood, D. Futyan, Y. Haddad, G. Hall, G. Iles, T. James, R. Lane, C. Laner, L. Lyons, A.-M. Magnan, S. Malik, L. Mastrolorenzo, J. Nash, A. Nikitenko\cmsAuthorMark48, J. Pela, M. Pesaresi, D.M. Raymond, A. Richards, A. Rose, E. Scott, C. Seez, S. Summers, A. Tapper, K. Uchida, M. Vazquez Acosta\cmsAuthorMark63, T. Virdee\cmsAuthorMark15, J. Wright, S.C. Zenz \cmsinstskip**Brunel University, Uxbridge, United Kingdom

** J.E. Cole, P.R. Hobson, A. Khan, P. Kyberd, I.D. Reid, P. Symonds, L. Teodorescu, M. Turner \cmsinstskip**Baylor University, Waco, USA

** A. Borzou, K. Call, J. Dittmann, K. Hatakeyama, H. Liu, N. Pastika \cmsinstskip**Catholic University of America, Washington, USA

** R. Bartek, A. Dominguez \cmsinstskip**The University of Alabama, Tuscaloosa, USA

** A. Buccilli, S.I. Cooper, C. Henderson, P. Rumerio, C. West \cmsinstskip**Boston University, Boston, USA

** D. Arcaro, A. Avetisyan, T. Bose, D. Gastler, D. Rankin, C. Richardson, J. Rohlf, L. Sulak, D. Zou \cmsinstskip**Brown University, Providence, USA

** G. Benelli, D. Cutts, A. Garabedian, J. Hakala, U. Heintz, J.M. Hogan, K.H.M. Kwok, E. Laird, G. Landsberg, Z. Mao, M. Narain, S. Piperov, S. Sagir, E. Spencer, R. Syarif \cmsinstskip**University of California, Davis, Davis, USA

** R. Band, C. Brainerd, D. Burns, M. Calderon De La Barca Sanchez, M. Chertok, J. Conway, R. Conway, P.T. Cox, R. Erbacher, C. Flores, G. Funk, M. Gardner, W. Ko, R. Lander, C. Mclean, M. Mulhearn, D. Pellett, J. Pilot, S. Shalhout, M. Shi, J. Smith, M. Squires, D. Stolp, K. Tos, M. Tripathi, Z. Wang \cmsinstskip**University of California, Los Angeles, USA

** M. Bachtis, C. Bravo, R. Cousins, A. Dasgupta, A. Florent, J. Hauser, M. Ignatenko, N. Mccoll, D. Saltzberg, C. Schnaible, V. Valuev \cmsinstskip**University of California, Riverside, Riverside, USA

** E. Bouvier, K. Burt, R. Clare, J. Ellison, J.W. Gary, S.M.A. Ghiasi Shirazi, G. Hanson, J. Heilman, P. Jandir, E. Kennedy, F. Lacroix, O.R. Long, M. Olmedo Negrete, M.I. Paneva, A. Shrinivas, W. Si, H. Wei, S. Wimpenny, B. R. Yates \cmsinstskip**University of California, San Diego, La Jolla, USA

** J.G. Branson, G.B. Cerati, S. Cittolin, M. Derdzinski, A. Holzner, D. Klein, G. Kole, V. Krutelyov, J. Letts, I. Macneill, D. Olivito, S. Padhi, M. Pieri, M. Sani, V. Sharma, S. Simon, M. Tadel, A. Vartak, S. Wasserbaech\cmsAuthorMark64, F. Würthwein, A. Yagil, G. Zevi Della Porta \cmsinstskip**University of California, Santa Barbara - Department of Physics, Santa Barbara, USA

** N. Amin, R. Bhandari, J. Bradmiller-Feld, C. Campagnari, A. Dishaw, V. Dutta, M. Franco Sevilla, C. George, F. Golf, L. Gouskos, J. Gran, R. Heller, J. Incandela, S.D. Mullin, A. Ovcharova, H. Qu, J. Richman, D. Stuart, I. Suarez, J. Yoo \cmsinstskip**California Institute of Technology, Pasadena, USA

** D. Anderson, J. Bendavid, A. Bornheim, J.M. Lawhorn, H.B. Newman, C. Pena, M. Spiropulu, J.R. Vlimant, S. Xie, R.Y. Zhu \cmsinstskip**Carnegie Mellon University, Pittsburgh, USA

** M.B. Andrews, T. Ferguson, M. Paulini, J. Russ, M. Sun, H. Vogel, I. Vorobiev, M. Weinberg \cmsinstskip**University of Colorado Boulder, Boulder, USA

** J.P. Cumalat, W.T. Ford, F. Jensen, A. Johnson, M. Krohn, S. Leontsinis, T. Mulholland, K. Stenson, S.R. Wagner \cmsinstskip**Cornell University, Ithaca, USA

** J. Alexander, J. Chaves, J. Chu, S. Dittmer, K. Mcdermott, N. Mirman, J.R. Patterson, A. Rinkevicius, A. Ryd, L. Skinnari, L. Soffi, S.M. Tan, Z. Tao, J. Thom, J. Tucker, P. Wittich, M. Zientek \cmsinstskip**Fairfield University, Fairfield, USA

** D. Winn \cmsinstskip**Fermi National Accelerator Laboratory, Batavia, USA

** S. Abdullin, M. Albrow, G. Apollinari, A. Apresyan, A. Apyan, S. Banerjee, L.A.T. Bauerdick, A. Beretvas, J. Berryhill, P.C. Bhat, G. Bolla, K. Burkett, J.N. Butler, A. Canepa, H.W.K. Cheung, F. Chlebana, M. Cremonesi, J. Duarte, V.D. Elvira, I. Fisk, J. Freeman, Z. Gecse, E. Gottschalk, L. Gray, D. Green, S. Grünendahl, O. Gutsche, R.M. Harris, S. Hasegawa, J. Hirschauer, Z. Hu, B. Jayatilaka, S. Jindariani, M. Johnson, U. Joshi, B. Klima, B. Kreis, S. Lammel, D. Lincoln, R. Lipton, M. Liu, T. Liu, R. Lopes De Sá, J. Lykken, K. Maeshima, N. Magini, J.M. Marraffino, S. Maruyama, D. Mason, P. McBride, P. Merkel, S. Mrenna, S. Nahn, V. O’Dell, K. Pedro, O. Prokofyev, G. Rakness, L. Ristori, B. Schneider, E. Sexton-Kennedy, A. Soha, W.J. Spalding, L. Spiegel, S. Stoynev, J. Strait, N. Strobbe, L. Taylor, S. Tkaczyk, N.V. Tran, L. Uplegger, E.W. Vaandering, C. Vernieri, M. Verzocchi, R. Vidal, M. Wang, H.A. Weber, A. Whitbeck \cmsinstskip**University of Florida, Gainesville, USA

** D. Acosta, P. Avery, P. Bortignon, A. Brinkerhoff, A. Carnes, M. Carver, D. Curry, S. Das, R.D. Field, I.K. Furic, J. Konigsberg, A. Korytov, K. Kotov, P. Ma, K. Matchev, H. Mei, G. Mitselmakher, D. Rank, L. Shchutska, D. Sperka, N. Terentyev, L. Thomas, J. Wang, S. Wang, J. Yelton \cmsinstskip**Florida International University, Miami, USA

** S. Linn, P. Markowitz, G. Martinez, J.L. Rodriguez \cmsinstskip**Florida State University, Tallahassee, USA

** A. Ackert, T. Adams, A. Askew, S. Hagopian, V. Hagopian, K.F. Johnson, T. Kolberg, T. Perry, H. Prosper, A. Santra, R. Yohay \cmsinstskip**Florida Institute of Technology, Melbourne, USA

** M.M. Baarmand, V. Bhopatkar, S. Colafranceschi, M. Hohlmann, D. Noonan, T. Roy, F. Yumiceva \cmsinstskip**University of Illinois at Chicago (UIC),  Chicago, USA

** M.R. Adams, L. Apanasevich, D. Berry, R.R. Betts, R. Cavanaugh, X. Chen, O. Evdokimov, C.E. Gerber, D.A. Hangal, D.J. Hofman, K. Jung, J. Kamin, I.D. Sandoval Gonzalez, M.B. Tonjes, H. Trauger, N. Varelas, H. Wang, Z. Wu, J. Zhang \cmsinstskip**The University of Iowa, Iowa City, USA

** B. Bilki\cmsAuthorMark65, W. Clarida, K. Dilsiz\cmsAuthorMark66, S. Durgut, R.P. Gandrajula, M. Haytmyradov, V. Khristenko, J.-P. Merlo, H. Mermerkaya\cmsAuthorMark67, A. Mestvirishvili, A. Moeller, J. Nachtman, H. Ogul\cmsAuthorMark68, Y. Onel, F. Ozok\cmsAuthorMark69, A. Penzo, C. Snyder, E. Tiras, J. Wetzel, K. Yi \cmsinstskip**Johns Hopkins University, Baltimore, USA

** B. Blumenfeld, A. Cocoros, N. Eminizer, D. Fehling, L. Feng, A.V. Gritsan, P. Maksimovic, J. Roskes, U. Sarica, M. Swartz, M. Xiao, C. You \cmsinstskip**The University of Kansas, Lawrence, USA

** A. Al-bataineh, P. Baringer, A. Bean, S. Boren, J. Bowen, J. Castle, S. Khalil, A. Kropivnitskaya, D. Majumder, W. Mcbrayer, M. Murray, C. Royon, S. Sanders, R. Stringer, J.D. Tapia Takaki, Q. Wang \cmsinstskip**Kansas State University, Manhattan, USA

** A. Ivanov, K. Kaadze, Y. Maravin, A. Mohammadi, L.K. Saini, N. Skhirtladze, S. Toda \cmsinstskip**Lawrence Livermore National Laboratory, Livermore, USA

** F. Rebassoo, D. Wright \cmsinstskip**University of Maryland, College Park, USA

** C. Anelli, A. Baden, O. Baron, A. Belloni, B. Calvert, S.C. Eno, C. Ferraioli, N.J. Hadley, S. Jabeen, G.Y. Jeng, R.G. Kellogg, J. Kunkle, A.C. Mignerey, F. Ricci-Tam, Y.H. Shin, A. Skuja, S.C. Tonwar \cmsinstskip**Massachusetts Institute of Technology, Cambridge, USA

** D. Abercrombie, B. Allen, V. Azzolini, R. Barbieri, A. Baty, R. Bi, K. Bierwagen, S. Brandt, W. Busza, I.A. Cali, M. D’Alfonso, Z. Demiragli, G. Gomez Ceballos, M. Goncharov, D. Hsu, Y. Iiyama, G.M. Innocenti, M. Klute, D. Kovalskyi, Y.S. Lai, Y.-J. Lee, A. Levin, P.D. Luckey, B. Maier, A.C. Marini, C. Mcginn, C. Mironov, S. Narayanan, X. Niu, C. Paus, C. Roland, G. Roland, J. Salfeld-Nebgen, G.S.F. Stephans, K. Tatar, D. Velicanu, J. Wang, T.W. Wang, B. Wyslouch \cmsinstskip**University of Minnesota, Minneapolis, USA

** A.C. Benvenuti, R.M. Chatterjee, A. Evans, P. Hansen, S. Kalafut, S.C. Kao, Y. Kubota, Z. Lesko, J. Mans, S. Nourbakhsh, N. Ruckstuhl, R. Rusack, N. Tambe, J. Turkewitz \cmsinstskip**University of Mississippi, Oxford, USA

** J.G. Acosta, S. Oliveros \cmsinstskip**University of Nebraska-Lincoln, Lincoln, USA

** E. Avdeeva, K. Bloom, D.R. Claes, C. Fangmeier, R. Gonzalez Suarez, R. Kamalieddin, I. Kravchenko, J. Monroy, J.E. Siado, G.R. Snow, B. Stieger \cmsinstskip**State University of New York at Buffalo, Buffalo, USA

** M. Alyari, J. Dolen, A. Godshalk, C. Harrington, I. Iashvili, A. Kharchilava, A. Parker, S. Rappoccio, B. Roozbahani \cmsinstskip**Northeastern University, Boston, USA

** G. Alverson, E. Barberis, A. Hortiangtham, A. Massironi, D.M. Morse, D. Nash, T. Orimoto, R. Teixeira De Lima, D. Trocino, R.-J. Wang, D. Wood \cmsinstskip**Northwestern University, Evanston, USA

** S. Bhattacharya, O. Charaf, K.A. Hahn, N. Mucia, N. Odell, B. Pollack, M.H. Schmitt, K. Sung, M. Trovato, M. Velasco \cmsinstskip**University of Notre Dame, Notre Dame, USA

** N. Dev, M. Hildreth, K. Hurtado Anampa, C. Jessop, D.J. Karmgard, N. Kellams, K. Lannon, N. Loukas, N. Marinelli, F. Meng, C. Mueller, Y. Musienko\cmsAuthorMark35, M. Planer, A. Reinsvold, R. Ruchti, N. Rupprecht, G. Smith, S. Taroni, M. Wayne, M. Wolf, A. Woodard \cmsinstskip**The Ohio State University, Columbus, USA

** J. Alimena, L. Antonelli, B. Bylsma, L.S. Durkin, S. Flowers, B. Francis, A. Hart, C. Hill, W. Ji, B. Liu, W. Luo, D. Puigh, B.L. Winer, H.W. Wulsin \cmsinstskip**Princeton University, Princeton, USA

** A. Benaglia, S. Cooperstein, O. Driga, P. Elmer, J. Hardenbrook, P. Hebda, D. Lange, J. Luo, D. Marlow, K. Mei, I. Ojalvo, J. Olsen, C. Palmer, P. Piroué, D. Stickland, A. Svyatkovskiy, C. Tully \cmsinstskip**University of Puerto Rico, Mayaguez, USA

** S. Malik, S. Norberg \cmsinstskip**Purdue University, West Lafayette, USA

** A. Barker, V.E. Barnes, S. Folgueras, L. Gutay, M.K. Jha, M. Jones, A.W. Jung, A. Khatiwada, D.H. Miller, N. Neumeister, J.F. Schulte, J. Sun, F. Wang, W. Xie \cmsinstskip**Purdue University Northwest, Hammond, USA

** T. Cheng, N. Parashar, J. Stupak \cmsinstskip**Rice University, Houston, USA

** A. Adair, B. Akgun, Z. Chen, K.M. Ecklund, F.J.M. Geurts, M. Guilbaud, W. Li, B. Michlin, M. Northup, B.P. Padley, J. Roberts, J. Rorie, Z. Tu, J. Zabel \cmsinstskip**University of Rochester, Rochester, USA

** B. Betchart, A. Bodek, P. de Barbaro, R. Demina, Y.t. Duh, T. Ferbel, M. Galanti, A. Garcia-Bellido, J. Han, O. Hindrichs, A. Khukhunaishvili, K.H. Lo, P. Tan, M. Verzetti \cmsinstskip**The Rockefeller University, New York, USA

** R. Ciesielski, K. Goulianos, C. Mesropian \cmsinstskip**Rutgers, The State University of New Jersey, Piscataway, USA

** A. Agapitos, J.P. Chou, Y. Gershtein, T.A. Gómez Espinosa, E. Halkiadakis, M. Heindl, E. Hughes, S. Kaplan, R. Kunnawalkam Elayavalli, S. Kyriacou, A. Lath, R. Montalvo, K. Nash, M. Osherson, H. Saka, S. Salur, S. Schnetzer, D. Sheffield, S. Somalwar, R. Stone, S. Thomas, P. Thomassen, M. Walker \cmsinstskip**University of Tennessee, Knoxville, USA

** M. Foerster, J. Heideman, G. Riley, K. Rose, S. Spanier, K. Thapa \cmsinstskip**Texas A&M University, College Station, USA

** O. Bouhali\cmsAuthorMark70, A. Castaneda Hernandez\cmsAuthorMark70, A. Celik, M. Dalchenko, M. De Mattia, A. Delgado, S. Dildick, R. Eusebi, J. Gilmore, T. Huang, T. Kamon\cmsAuthorMark71, R. Mueller, Y. Pakhotin, R. Patel, A. Perloff, L. Perniè, D. Rathjens, A. Safonov, A. Tatarinov, K.A. Ulmer \cmsinstskip**Texas Tech University, Lubbock, USA

** N. Akchurin, J. Damgov, F. De Guio, C. Dragoiu, P.R. Dudero, J. Faulkner, E. Gurpinar, S. Kunori, K. Lamichhane, S.W. Lee, T. Libeiro, T. Peltola, S. Undleeb, I. Volobouev, Z. Wang \cmsinstskip**Vanderbilt University, Nashville, USA

** S. Greene, A. Gurrola, R. Janjam, W. Johns, C. Maguire, A. Melo, H. Ni, P. Sheldon, S. Tuo, J. Velkovska, Q. Xu \cmsinstskip**University of Virginia, Charlottesville, USA

** M.W. Arenton, P. Barria, B. Cox, R. Hirosky, A. Ledovskoy, H. Li, C. Neu, T. Sinthuprasith, X. Sun, Y. Wang, E. Wolfe, F. Xia \cmsinstskip**Wayne State University, Detroit, USA

** C. Clarke, R. Harr, P.E. Karchin, J. Sturdy, S. Zaleski \cmsinstskip**University of Wisconsin - Madison, Madison, WI, USA

** D.A. Belknap, J. Buchanan, C. Caillol, S. Dasu, L. Dodd, S. Duric, B. Gomber, M. Grothe, M. Herndon, A. Hervé, U. Hussain, P. Klabbers, A. Lanaro, A. Levine, K. Long, R. Loveless, G.A. Pierro, G. Polese, T. Ruggles, A. Savin, N. Smith, W.H. Smith, D. Taylor, N. Woods \cmsinstskip1:  Also at Vienna University of Technology, Vienna, Austria

2:  Also at State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing, China

3:  Also at Universidade Estadual de Campinas, Campinas, Brazil

4:  Also at Universidade Federal de Pelotas, Pelotas, Brazil

5:  Also at Université Libre de Bruxelles, Bruxelles, Belgium

6:  Also at Joint Institute for Nuclear Research, Dubna, Russia

7:  Also at Helwan University, Cairo, Egypt

8:  Now at Zewail City of Science and Technology, Zewail, Egypt

9:  Now at Fayoum University, El-Fayoum, Egypt

10: Also at British University in Egypt, Cairo, Egypt

11: Now at Ain Shams University, Cairo, Egypt

12: Also at Université de Haute Alsace, Mulhouse, France

13: Also at Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, Moscow, Russia

14: Also at Tbilisi State University, Tbilisi, Georgia

15: Also at CERN, European Organization for Nuclear Research, Geneva, Switzerland

16: Also at RWTH Aachen University, III. Physikalisches Institut A, Aachen, Germany

17: Also at University of Hamburg, Hamburg, Germany

18: Also at Brandenburg University of Technology, Cottbus, Germany

19: Also at Institute of Nuclear Research ATOMKI, Debrecen, Hungary

20: Also at MTA-ELTE Lendület CMS Particle and Nuclear Physics Group, Eötvös Loránd University, Budapest, Hungary

21: Also at Institute of Physics, University of Debrecen, Debrecen, Hungary

22: Also at Indian Institute of Technology Bhubaneswar, Bhubaneswar, India

23: Also at Institute of Physics, Bhubaneswar, India

24: Also at University of Visva-Bharati, Santiniketan, India

25: Also at University of Ruhuna, Matara, Sri Lanka

26: Also at Isfahan University of Technology, Isfahan, Iran

27: Also at Yazd University, Yazd, Iran

28: Also at Plasma Physics Research Center, Science and Research Branch, Islamic Azad University, Tehran, Iran

29: Also at Università degli Studi di Siena, Siena, Italy

30: Also at Purdue University, West Lafayette, USA

31: Also at International Islamic University of Malaysia, Kuala Lumpur, Malaysia

32: Also at Malaysian Nuclear Agency, MOSTI, Kajang, Malaysia

33: Also at Consejo Nacional de Ciencia y Tecnología, Mexico city, Mexico

34: Also at Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland

35: Also at Institute for Nuclear Research, Moscow, Russia

36: Now at National Research Nuclear University ’Moscow Engineering Physics Institute’ (MEPhI), Moscow, Russia

37: Also at St. Petersburg State Polytechnical University, St. Petersburg, Russia

38: Also at University of Florida, Gainesville, USA

39: Also at P.N. Lebedev Physical Institute, Moscow, Russia

40: Also at California Institute of Technology, Pasadena, USA

41: Also at Budker Institute of Nuclear Physics, Novosibirsk, Russia

42: Also at Faculty of Physics, University of Belgrade, Belgrade, Serbia

43: Also at INFN Sezione di Roma; Sapienza Università di Roma, Rome, Italy

44: Also at University of Belgrade, Faculty of Physics and Vinca Institute of Nuclear Sciences, Belgrade, Serbia

45: Also at Scuola Normale e Sezione dell’INFN, Pisa, Italy

46: Also at National and Kapodistrian University of Athens, Athens, Greece

47: Also at Riga Technical University, Riga, Latvia

48: Also at Institute for Theoretical and Experimental Physics, Moscow, Russia

49: Also at Albert Einstein Center for Fundamental Physics, Bern, Switzerland

50: Also at Gaziosmanpasa University, Tokat, Turkey

51: Also at Istanbul Aydin University, Istanbul, Turkey

52: Also at Mersin University, Mersin, Turkey

53: Also at Cag University, Mersin, Turkey

54: Also at Piri Reis University, Istanbul, Turkey

55: Also at Adiyaman University, Adiyaman, Turkey

56: Also at Izmir Institute of Technology, Izmir, Turkey

57: Also at Necmettin Erbakan University, Konya, Turkey

58: Also at Marmara University, Istanbul, Turkey

59: Also at Kafkas University, Kars, Turkey

60: Also at Istanbul Bilgi University, Istanbul, Turkey

61: Also at Rutherford Appleton Laboratory, Didcot, United Kingdom

62: Also at School of Physics and Astronomy, University of Southampton, Southampton, United Kingdom

63: Also at Instituto de Astrofísica de Canarias, La Laguna, Spain

64: Also at Utah Valley University, Orem, USA

65: Also at BEYKENT UNIVERSITY, Istanbul, Turkey

66: Also at Bingol University, Bingol, Turkey

67: Also at Erzincan University, Erzincan, Turkey

68: Also at Sinop University, Sinop, Turkey

69: Also at Mimar Sinan University, Istanbul, Istanbul, Turkey

70: Also at Texas A&M University at Qatar, Doha, Qatar

71: Also at Kyungpook National University, Daegu, Korea