Z boson production in Pb+Pb collisions at s NN − − − √ = 5.02 TeV measured by the ATLAS experiment
EEUROPEAN ORGANISATION FOR NUCLEAR RESEARCH (CERN)
Submitted to: Phys. Lett. B. CERN-EP-2019-18213th November 2019 Z boson production in Pb+Pb collisions at √ s NN = 5.02 TeV measured by the ATLAS experiment The ATLAS Collaboration
The production yield of Z bosons is measured in the electron and muon decay channels inPb+Pb collisions at √ s NN = 5.02 TeV with the ATLAS detector. Data from the 2015 LHCrun corresponding to an integrated luminosity of 0.49 nb − are used for the analysis. The Z boson yield, normalised by the total total number of minimum-bias events and the meannuclear thickness function, is measured as a function of dilepton rapidity and event centrality.The measurements in Pb+Pb collisions are compared with similar measurements made inproton–proton collisions at the same centre-of-mass energy. The nuclear modification factoris found to be consistent with unity for all centrality intervals. The results are compared withtheoretical predictions obtained at next-to-leading order using nucleon and nuclear partondistribution functions. The normalised Z boson yields in Pb+Pb collisions lie 1–3 σ above thepredictions. The nuclear modification factor measured as a function of rapidity agrees withunity and is consistent with a next-to-leading-order QCD calculation including the isospineffect. © 2019 CERN for the benefit of the ATLAS Collaboration.Reproduction of this article or parts of it is allowed as specified in the CC-BY-4.0 license. a r X i v : . [ nu c l - e x ] O c t Introduction
The measurement of electroweak (EW) boson production is a key part of the heavy-ion (HI) physicsprogramme at the Large Hadron Collider (LHC). Isolated photons and heavy vector bosons, Z and W , arepowerful tools to probe the initial stages of HI collisions. After being created at the initial stage of thecollision in high-momentum exchange processes, Z and W bosons decay much faster than the timescale ofthe medium’s evolution. Their leptonic decay products are generally understood to not be affected by thestrong interaction; hence they carry information about the initial stage of the collision and the partonicstructure of the nuclei.Measurements performed by the ATLAS and CMS experiments with Z and W bosons decaying leptonicallyshow that production rates of these non-strongly interacting particles are proportional to the amount ofnuclear overlap, quantified by the mean nuclear thickness function, (cid:104) T AA (cid:105) [1–6]. Results obtained withisolated high-energy photons [7, 8] are also consistent with this observation.The transverse momentum and rapidity distribution of Z bosons and the pseudorapidity distribution ofmuons originating from W bosons measured in Pb+Pb collisions at √ s NN = .
76 TeV have been found to begenerally consistent with perturbative quantum chromodynamics (pQCD) calculations of nucleon–nucleoncollisions scaled by (cid:104) T AA (cid:105) . Production of Z bosons in Pb+Pb collisions was found to be consistent withnext-to-leading-order (NLO) pQCD calculations that do not include nuclear modifications in the treatmentof parton distribution functions (PDFs). However, some nuclear modification of PDFs could not beexcluded within the precision of the existing Pb+Pb measurements [1, 2, 7]. The recent ALICE result at √ s NN = .
02 TeV shows better agreement with nPDF calculations at forward rapidities [9].On the other hand, the study of asymmetric p +Pb collisions at √ s NN = .
02 TeV shows that including nuclearmodifications of PDFs gives a substantially better description of the data than using a free proton PDF. Thisis seen by comparing the Z boson cross section in p +Pb collisions with pQCD calculations [10–13] andrecently also the W boson cross section at √ s NN = .
02 TeV and √ s NN = .
16 TeV [13, 14]. In addition,studies of Z bosons differentially in p +Pb centrality demonstrate that they are a sensitive test of the Glaubermodel description of nuclear geometry [11].This letter presents results on Z boson production yield measurement in the Z → µµ and Z → ee decay channels in Pb+Pb collisions at √ s NN = .
02 TeV with the ATLAS detector at the LHC. The datasample was collected in November 2015 and corresponds to an integrated luminosity of 0.49 nb − . Theobservables under study are the yield of produced Z bosons in the fiducial kinematic region defined bydetector acceptance and lepton kinematics normalised to the number of minimum-bias events, measureddifferentially in rapidity and event centrality. The Pb+Pb data are compared with pQCD calculations, andthe nuclear modification factor is measured relative to previously measured pp cross sections [15]. The ATLAS detector [16] covers nearly the entire solid angle around the collision point. It consists ofan inner tracking detector surrounded by a thin superconducting solenoid, electromagnetic and hadronic ATLAS uses a right-handed coordinate system with its origin at the nominal interaction point (IP) in the centre of the detectorand the z -axis along the beam pipe. The x -axis points from the IP to the centre of the LHC ring, and the y -axis pointsupwards. Cylindrical coordinates ( r , φ ) are used in the transverse plane, φ being the azimuthal angle around the z -axis. Thepseudorapidity is defined in terms of the polar angle θ as η = − ln tan ( θ / ) . | η | < .
5. The high-granularity silicon pixel detector covers the vertex region and typicallyprovides four measurements per track, the first hit being in the insertable B-layer [17, 18] in operationsince 2015. It is followed by the silicon microstrip tracker, which usually provides eight measurements pertrack. These silicon detectors are complemented by the transition-radiation tracker, which enables radiallyextended track reconstruction up to | η | = . | η | < .
9. Within the region | η | < . | η | < .
8, to correct for energyloss in material upstream of the calorimeters. Hadronic calorimetry is provided by the scintillator-tilecalorimeter, segmented into three barrel structures within | η | < .
7, and two LAr hadronic endcapcalorimeters. The forward calorimeter (FCal) is a LAr sampling calorimeter located on either side of theinteraction point. It covers 3 . < | η | < . | η | > .
3, and are primarily sensitive to spectatorneutrons.The muon spectrometer comprises separate trigger and high-precision tracking chambers measuring thedeflection of muons in a magnetic field generated by superconducting air-core toroids. The precisionchamber system covers the region | η | < . | η | < . All of the analysed data were recorded in periods with stable beam, detector, and trigger operations.Candidate events are required to have at least one primary vertex reconstructed from the inner-detectortracks. In addition, a trigger selection is applied, requiring a muon or an electron candidate above a p T threshold of 8 GeV or 15 GeV, respectively. The electron-trigger candidate is further required to satisfya set of loose criteria for the electromagnetic shower shapes [20]. The trigger algorithm implements anevent-by-event estimation and subtraction of the underlying-event contribution to the transverse energydeposited in each calorimeter cell [21]. For both the electron and muon candidates, further requirementsare applied to suppress electromagnetic background contributions, as described in Section 4.2.Muon candidates reconstructed offline must satisfy p T >
20 GeV and | η | < 2.5 and pass the requirements of‘medium’ identification optimised for 2015 analysis conditions [22]. Offline selected electron candidatesare required to have p T >
20 GeV and | η | < .
47, although candidates within the transition region betweenbarrel and endcap calorimeters (1 . < | η | < .
52) are rejected. In addition, ‘loose’ likelihood-based3dentification is applied, developed for the Pb+Pb data conditions and based on a general strategy describedin Ref. [23].Events with a Z boson candidate are selected by requiring exactly two opposite-charge muons or electrons,at least one of which is matched to a lepton selected at trigger level. The dilepton invariant mass mustsatisfy the requirement 66 < m (cid:96)(cid:96) <
116 GeV. A total of 5347 Z boson candidates are found in the muonchannel and 4047 in the electron channel.In order to estimate the geometric characteristics of HI collisions, it is common to classify the eventsaccording to the amount of nuclear overlap in the collision. The quantity used to estimate the collisiongeometry is called the ‘collision centrality’. The centrality determination is based on the total transverseenergy measured by both FCal detectors in each event, Σ E FCalT . This quantity is then mapped to geometricquantities, such as the average number of participating nucleons, (cid:104) N part (cid:105) , and the mean nuclear thicknessfunction, (cid:104) T AA (cid:105) , which quantifies the amount of nuclear overlap in a centrality class and is evaluated usinga Glauber calculation [24, 25]. The mapping is based on specific studies of an event sample withoutadditional Pb+Pb collisions within the same or neighbouring bunch crossings (pile-up) collected withminimum-bias (MB) triggers. A special treatment is employed for events in the 20% most peripheralinterval, where diffractive and photonuclear processes contribute significantly to the MB event sample.This requires extrapolating from the total number of MB events in this region and employing a specialrequirement on the Z boson event topology, as described in Section 4.2. Table 1 summarises the relationshipbetween centrality, (cid:104) N part (cid:105) , and (cid:104) T AA (cid:105) as calculated with Glauber MC v2.4 [26], which incorporates nucleardensities averaged over protons and neutrons. The total number of MB events in the 0–80% centralityinterval is ( . ± . ) × , which is then distributed in different centrality intervals according totheir size. The quoted uncertainty on the number of MB events includes variations on the Σ E FCalT valuecorresponding to the 0–80% centrality interval estimated with the Glauber model. This sample is obtainedby selecting events passing MB triggers and excluding the events with a pile-up contribution, where thetotal sampled integrated luminosity corresponds to the signal selection [25].
Table 1: Centrality intervals and their corresponding geometric quantities with systematic uncertainties, fromRef. [26].
Centrality [%] (cid:104) N part (cid:105) (cid:104) T AA (cid:105) [mb − ] Centrality [%] (cid:104) N part (cid:105) (cid:104) T AA (cid:105) [mb − ]0–2% 399 . ± . . ± .
25 20–25% 205 . ± . . ± . . ± . . ± .
21 25–30% 172 . ± . . ± . . ± . . ± .
21 30–40% 131 . ± . . ± . . ± . . ± .
20 40–50% 87 . ± . . ± . . ± . . ± .
19 50–60% 53 . ± . . ± . . ± . . ± .
18 60–80% 23 . ± . . ± . . ± . . ± .
17 80–100% 4 . ± .
36 0 . ± . . ± . . ± . Z bosons were generated with the Powheg-Box v1 MC program [29–32] interfaced to the Pythia 8.186 parton shower model [33]. The CT10 PDF set [34] was used in the matrix4lement, while the CTEQ6L1 PDF set [35] was used with the AZNLO [36] set of generator-parametervalues (tune) for the modelling of non-perturbative effects in the initial-state parton shower. The Photos++v3.52 program [37] was used for final-state photon radiation in EW processes.A sample of top-quark pair ( t ¯ t ) production was generated with the Powheg-Box v2 generator, whichuses NLO matrix-element calculations [38] together with the CT10f4 PDF set [39]. The parton shower,fragmentation and underlying event in nucleon–nucleon collisions were simulated using Pythia 6.428 [40]with the CTEQ6L1 PDF set and the corresponding Perugia 2012 tune (P2012) [41]. The top-quark masswas set to 172.5 GeV. The EvtGen v1.2.0 program [42] was used to model bottom and charm hadrondecays for all versions of Pythia. The total Z boson and top-quark yields in MC samples are normalisedusing the results of NLO QCD calculations.The signal MC samples were produced with different nucleon–nucleon combinations ( pp , pn , nn ) weightedto reflect the isospin composition of lead nuclei. For lead, A =
208 and Z =
82, so all samples with twoneutrons have a weight of ([ A − Z ]/ Z ) = pn , np ) each have weights of 23.9%.Once produced, the simulated events were overlaid with MB events taken during the Pb+Pb run. The overlayof data events was done such that the MC simulation accurately reflects detector occupancy conditionspresent in the Pb+Pb run. The MB events used for the overlay were sampled such that the centralitydistribution, based on the total transverse energy deposited in the forward calorimeters, approximates thatof Z boson events, which are generally biased to more-central collisions. The simulated events were finallyreconstructed by the standard ATLAS reconstruction software. The differential Z boson production yield per MB event is measured within a fiducial phase space definedby p (cid:96) T >
20 GeV, | η (cid:96) | < . < m (cid:96)(cid:96) <
116 GeV. The yields in both the electron and muon channelare calculated using N fid Z = N Z − B Z (cid:15) Z trig · C Z , (1)where N Z and B Z are the number of selected events in data and the expected number of background events,respectively, and (cid:15) Z trig is the trigger efficiency per Z boson candidate measured in data and described inSection 4.3.A correction for the reconstruction efficiency, momentum resolution and the final-state radiation effects isapplied with the bin-by-bin correction factor C Z which is obtained from MC simulation as C Z = N MC , sel Z N MC , fid Z . Here, N MC , sel Z is the number of events passing the signal selection at the detector level. The number ofselected events is corrected for measured differences between data and simulation in lepton reconstructionand identification efficiencies. The denominator N MC , fid Z is computed by applying the fiducial phase-spacerequirements to the generator-level leptons originating from Z boson decays. The measurement is5orrected for QED final-state radiation effects by using the generator-level lepton kinematics before photonradiation.The value of C Z in the fiducial acceptance averaged over all centralities is determined from MC simulationafter reweighting as explained in Section 3. It is 0 .
659 and 0 .
507 in the Z → µ + µ − and Z → e + e − decaychannels, respectively. The uncertainty due to the size of the simulated sample is at the level of 0.1% foreach decay channel and is not the dominant uncertainty.The rapidity, momentum and centrality dependence of C Z is calculated from the simulation as C Z ( p T , y , Σ E FCalT ) = F ( p T , y ) G ( y , Σ E FCalT ) , (2)where F ( p T , y ) is the centrality-averaged efficiency calculated per y and p T interval of the dilepton systemand G ( y , Σ E FCalT ) is a parabolic parameterisation of a correction factor accounting for the centrality andrapidity dependences of the efficiency. In each rapidity bin, the factor G is obtained from a fit of the ratioof the efficiency in a particular centrality bin to the value averaged over all possible centrality values.Nuclear modification is quantified by measuring the ratio of the Z boson production rate, scaled by themean nuclear thickness function, to the Z boson production cross section in pp collisions, and is called thenuclear modification factor: R AA ( y ) = (cid:104) T AA (cid:105) N evt d N Z Pb + Pb / d y d σ Zpp / d y , where (cid:104) T AA (cid:105) is the nuclear thickness function in a given centrality class, ( / N evt ) d N Z Pb + Pb / d y is thedifferential yield of Z bosons per inelastic MB event measured in Pb+Pb collisions and d σ Zpp / d y is thedifferential Z boson cross section measured in pp collisions [15]. A deviation from unity in R AA indicatesthe nuclear modification of the observable. The value of R AA is expected to be greater than unity by about2.5%, based on MC simulation, due to the higher Z boson production cross section in proton–neutronand neutron–neutron interactions which are present in Pb+Pb collisions and amount to 84.5% of the totalhadronic cross section. This is later referred to as the ‘isospin effect’ and is not accounted for in thedefinition of R AA . There are two background source categories studied in this analysis. The first includes the same backgroundsources that are studied in pp collisions [15] and the second includes additional background sources specificto the Pb+Pb collision system.Background contributions in the first category are expected from Z → τ + τ − , top-quark pair productionand multi-jet events. The first two contributions are evaluated from dedicated simulation samples, whereasthe multi-jet background contribution is derived using a data-driven approach. The Z → τ + τ − backgroundis found to be 0.05% of all signal candidates in the muon channel and 0.06% in the electron channel. Thetop-quark background amounts to 0.08% in the muon channel and 0.05% in the electron channel. Thebackground contribution from W boson decays and W +jet production is found to be negligible.The multi-jet background originates from jets, misidentified hadrons and, in the electron channel, fromconverted photons. In the muon channel, its contribution is estimated from the distribution of the same-sign Z boson candidates in rapidity and centrality. Due to the low charge misidentification rate in the muonspectrometer, their invariant mass distribution does not exhibit a peak in the Z boson mass region. In the6uon channel this background amounts to 0.5% of all signal candidates. In the electron channel, there isa significant contribution from charge misidentification, fakes and conversions. The electron same-signpairs therefore cannot be used to estimate the multi-jet background. This contribution to the selectedevent sample in the electron channel is estimated using a background template obtained from the data in Z boson rapidity and event centrality. The template is derived from a subset of the signal sample thatcorresponds to electrons from jets, i.e. electrons with a very poor reconstruction quality. It is normalised tothe number of same-sign data candidates in the low-mass region of 60 < m ee <
70 GeV after the signalMC subtraction. Due to the small number of signal candidates satisfying this condition, same-sign electronpairs with the same kinematic requirements are also added to this background template. The shape of theobtained multijet template is shown in Figure 1. This background amounts to 2% of all signal candidates inthe electron channel.The background contributions specific to Pb+Pb come from two main sources. The first is due to pile-upwhen more than a single Pb+Pb collision is recorded simultaneously or in a nearby bunch crossing. Thesecond is the production of additional Z boson candidates by photon-induced reactions produced bythe intense electromagnetic fields generated by the colliding ions (below referred to as ‘electromagneticbackground’). Pile-up distorts the transverse energy measured in the FCal and causes reconstructed Z bosons to be assigned to an incorrect centrality interval. Pile-up events from other collisions in the samebunch crossing (in-time pile-up) increase the Σ E FCalT , shifting the Z boson candidate to a more-centralinterval. Alternatively, if a pile-up collision precedes the trigger event (out-of-time pile-up), its contributionto the Σ E FCalT can be negative, due to the time response of the electronic signal shapers used in thecalorimeters [43]. In this case, the Z boson candidate is shifted to a more-peripheral interval. Bothprocesses depend on the instantaneous luminosity during data taking. At any time during the HI run thenumber of hadronic interactions per bunch crossing was less than 0.01. To preserve the accuracy of the totalyield measurement, no pile-up removal procedure was applied to the selected events. However, due to thefact that the Z boson production scales linearly with (cid:104) T AA (cid:105) [1], the increase in the FCal transverse energyin in-time pile-up events transfers candidates from less populated to more-populated centrality intervals,thus having a very small effect and changing the average number of counts in the most central collisions byan insignificant amount. Contrary to that, the reduction in the Σ E FCalT transfers out-of-time pile-up eventsfrom more-populated to less-populated centrality intervals, thus making a larger relative contributionto the more-peripheral events. The effect has been studied using several independent data-driven andsimulation-based approaches. The largest contribution to the most peripheral 80–100% centrality intervaldue to this type of the pile-up is less than 2%, i.e. less than one count, and is significantly less in any othercentrality range.A non-negligible relative contribution to the dileptons in the Z boson mass range in peripheral centralityintervals is expected from electromagnetic background sources. On the other hand, the expected rateof signal events in those peripheral centrality bins is low. Two photon-induced processes are expectedto contribute to the background: photon–photon scattering, γγ → (cid:96) + (cid:96) − [44–46] and photon–nucleusscattering γ + A → Z → (cid:96) + (cid:96) − [47]. Although measurements of exclusive high-mass dilepton productionhave been performed in pp and Pb+Pb collisions by ATLAS [48] and in pp collisions by CMS [49] aphoto-nuclear Z boson production has not yet been observed in HI collisions. When the impact parameterof the photon-induced processes is larger than twice the nuclear radius such processes are referred toas ultra-peripheral collisions, and in these they are not obscured by hadronic interactions. Both physicsprocesses are characterised by large rapidity gaps on one or both sides of the detector (regions with noparticle production recorded in the detector), which are used in this analysis to measure and subtractthese backgrounds. The rapidity gap estimation is implemented using a similar technique as developed inRef. [50]. 7 [GeV] mm m - -
10 110 E v en t s / G e V ATLAS -1 =5.02 TeV, 0.49 nb NN s Pb+Pb, - m + m fi Z Data - m + m fi Z EM backgroundMulti-jet - t + t fi Z Top quarks
60 70 80 90 100 110 120 [GeV] mm m P r ed . D a t a [GeV] ee m - -
10 110 E v en t s / G e V ATLAS -1 =5.02 TeV 0.49 nb NN s Pb+Pb, - e + e fi Z Data - e + e fi Z EM backgroundMulti-jet - t + t fi Z Top quarks
60 70 80 90 100 110 120 [GeV] ee m P r ed . D a t a Figure 1: Centrality-integrated detector-level invariant mass distribution of (left) dimuon and (right) dielectron pairstogether with the Z → τ + τ − , top quark, multi-jet and EM background contributions. Only the statistical uncertaintiesof the data are shown. In the 50–100% (peripheral) centrality intervals, there is an additional requirement of a ZDC signalcoincidence in order to suppress the electromagnetic background contributions. The energy measuredin either detector is required to be at least 1 TeV, corresponding to 40% of the energy deposition of asingle neutron. Without using any ZDC coincidence requirement in the event selection, 34 events witha rapidity gap greater than 2.5 units are found in the two decay channels. Since the estimated numberof hadronic Z boson candidates with such a gap is below 0.05, all of these events are considered to beproduced by photon-induced reactions and are removed from the sample. Events without gaps can have aphoton-induced dilepton pair as well, if the rapidity gap is filled by particles originating from a simultaneousnucleon–nucleon interaction. These events would appear in the centrality intervals defined by the Σ E FCalT deposition from the hadronic interaction.Following Ref. [51], photon-induced reactions occurring simultaneously with hadronic collisions can beidentified using both the angular and momentum correlations of final-state dilepton pairs. One variableused to quantify these correlations is the dilepton acoplanarity, defined as α ≡ − | φ + − φ − |/ π , where φ ± are the azimuthal angles of the two opposite-charge leptons. The same observable is used in this analysis toextract the contribution of photon-induced reactions to the measured Z boson production. Based on the MCsignal simulation and measurements in the 0–50% centrality interval, (13 . ± . Z boson candidatesproduced by hadronic collisions have acoplanarity below 0.01. On the other hand, among the 34 eventswith a rapidity gap greater than 2.5 units which were rejected from the sample as pure photon-inducedevents, 26 are found to have α < .
01, corresponding to a fraction of 76%. This demonstrates that theacoplanarity is sensitive to photon-induced reactions in the Z boson invariant-mass region. This allows thephoton-induced background to be estimated in all centrality intervals by comparing the number of Z bosoncandidates in a given centrality interval with the number of candidates with α < . ± ± ± After subtracting background contributions, the number of Z boson candidates is corrected for the triggerefficiency and detection efficiency, according to Eq. (1). All the correction factors are derived directly fromthe current data set used in the analysis, with the exception of the lepton momentum calibration correctionsthat are derived from pp collision data, and extrapolated to the Pb+Pb dataset conditions. The triggerefficiency per reconstructed Z candidate (cid:15) Z trig is derived from the efficiency of the single-lepton trigger (cid:15) (cid:96) via the relation (cid:15) Z trig = − ( − (cid:15) (cid:96) )( − (cid:15) (cid:96) ) , where the indices refer to the two leptons forming the candidatepair. In order to obtain (cid:15) Z trig as a function of the dilepton p T and y which is further applied as a correctionper dilepton candidate, kinematic distributions of the decay products are taken from MC simulation.Muon and electron trigger efficiencies are measured using a tag-and-probe method [19, 22, 23] as a functionof η and φ . The tag lepton is required to be reconstructed with high quality and very low probabilityof background contamination and to be matched to a lepton selected at trigger level. The probe lepton,satisfying the analysis reconstruction and identification requirements, is paired to it to give an invariantmass in the range 66 < m (cid:96)(cid:96) <
116 GeV. The background contribution to this measurement is estimatedfrom the number of same-sign pairs and amounts to 0.8% and 3.5% in the muon and electron channels,respectively.The single-muon trigger efficiency in the endcap region of the detector (1 . < | η | < .
4) is measuredto be around 85%, and in the barrel region ( | η | < .
05) it varies between 60% and 80%. A significantdependence of the efficiency on the muon azimuthal angle φ was measured and thus the trigger efficiencycorrection is derived as a function of both φ and η . The single-electron trigger efficiency is measured to bearound 95% in the endcap region of the calorimeter (1 . < | η | < .
47) and it increases slightly to 97%in the barrel ( | η | < . p T was measured, and the efficiencyrises from 85% to 97% in the range from 20 to 100 GeV integrated over η . The single-electron triggerefficiency is thus derived as a function of p T and η . The average (cid:15) Z trig is (94 . ± . . ± . Z → µ + µ − events [22] and compared with simulation. Ratios of the efficiencies determined indata and simulation are applied as scale factors (SF) to correct the simulated events. Since the measuredefficiencies are found to have negligible dependence on the muon momentum in the selected kinematicregion and a very weak centrality dependence, the SF are evaluated only as a function of muon η . Thecentrality dependence of the SF is taken into account in the evaluation of systematic uncertainties. Thecombined reconstruction and identification efficiency for medium-quality muons typically exceeds 84% inboth the data and simulation with good agreement between the two estimates. The largest difference is9bserved in the endcap region ( | η | > . η regions are asfollows: 0 . ± .
01 for | η | < .
8, 0 . ± .
01 for 0 . < | η | < . . ± .
02 for | η | > . Z → e + e − events,as described in Ref. [23], and compared with simulation to derive electron scale factors. Measurementsare performed as a function of the electron η , p T and event centrality. The electron reconstruction andidentification efficiency is measured to be typically 70% in the endcap ( | η | > .
52) with good agreementbetween the data and the simulation. The SF is measured to be 1% away from unity with a precision of 3%in that region. In the barrel region ( | η | < .
37) the efficiency is measured to be around 80% while in theMC simulation the efficiency reaches 85%. Therefore, in this region a significant SF is applied, measuredwith a precision of 3–5%.The lepton momentum scale and resolution corrections are derived using the pp signal MC samples and areapplied to the simulation for both the electrons and muons. For the reconstructed muons, these correctionsare derived as a function of the muon η and φ [22]. The correction factors are chosen such that theyminimise the χ between the muon-pair invariant mass distributions in data and simulation. The energyscale of reconstructed electrons is corrected by applying to the data a per-electron correction factor. Themomentum scale correction factors are derived from a comparison of the electron-pair invariant massbetween simulation and data. In both channels, the trigger efficiency is derived from the tag-and-probe results in the data. The statisticallimitation of the measured sample determines the uncertainty associated with the trigger correction.Although the uncertainties in each bin are relatively large in the muon trigger efficiency, after propagatingthis uncertainty to the dimuon efficiency, where only one of the muons is required to fire the trigger,the total uncertainty is quite small, between 0.2% and 0.5% when derived as a function of centralityand 0.1–0.2% when derived as a function of Z boson rapidity. The uncertainty is propagated using MCpseudo-experiments and the uncertainties in the linear fit coefficients of the trigger efficiency as a functionof centrality. In the electron channel this uncertainty is at most 0.5%.The NLO cross section of the background samples of Z → τ + τ − and top-quark production is varied by 10%to derive the corresponding uncertainties [15]. However, in both decay channels the multi-jet backgrounddominates the uncertainty contribution. In the muon channel, the multijet background contribution isvaried by 10%, which produces 0.01–0.1% uncertainty in rapidity bins and up to 0.2% uncertainty incentrality bins. In the electron channel, the multi-jet template normalisation is varied by 20%, whichcorresponds to the level of statistical uncertainty in the number of same-sign candidates in the low-masscontrol region. The overall contribution to the systematic uncertainty is about 0.5% in rapidity bins and0.5–2% in centrality bins.In the 50–100% centrality interval, the uncertainty in subtracting the photon-induced background isevaluated by considering two sources. The first source is the compatibility between the acoplanarity cutefficiencies for hadronic Z boson production evaluated from data and simulation. An uncertainty of 0.4%accounts for this difference. For the second source, the uncertainty in the background rejection efficiencyof the acoplanarity cut is evaluated from the candidates with large rapidity gaps. This uncertainty has twocontributions. One is the statistical uncertainty of the event sample with large rapidity gaps, which amounts10o 7%. The other contribution is due to the observed differences between the acoplanarity distributions forelectrons and muons, which amounts to about 8%. In the 0–50% centrality interval, where the backgroundsubtraction is not performed, an uncertainty of 0.4%, evaluated from the difference between the data andsimulation acoplanarity distributions, is introduced to account for a possible residual EM backgroundcontribution.Uncertainties in the determination of lepton reconstruction and identification efficiency scale factors, aswell as the parameterisation of the centrality dependence of the total correction affect the measurementsthrough the correction factors C Z .In the muon channel, the scale factors in the three η regions described in Section 4.3 are modified by theirerrors to derive the corresponding systematic uncertainty of C Z . In addition, the impact of the measuredSF dependence of the final C Z value on the event centrality is also evaluated. The total relative uncertaintyfrom these two sources ranges from 3.1% at midrapidity ( | y | < .
5) to 4.5% at forward Z boson rapiditiesand gives a contribution, constant as a function of the event centrality, of ∼ Z boson yields.The main contribution to the systematic uncertainty in the electron channel comes from the uncertainties inmeasuring the reconstruction efficiency scale factor. Uncertainties related to this efficiency are classified aseither correlated or uncorrelated, and are propagated accordingly to the final measurement uncertainty.The correlated uncertainty component of the SF is obtained by varying the requirements on the tagelectron identification and isolation and on the invariant mass of the tag-and-probe pair. The statistical,uncorrelated, components of the scale factor uncertainties are propagated to the measurements via MCpseudo-experiments, while the systematic components are propagated as a single variation fully correlatedacross all electron η intervals. This source gives a 2.5–5% uncertainty as a function of rapidity and around3% for all centrality intervals.The effect of the calibration and energy scale correction uncertainty of electrons and muons is negligible.An additional uncertainty of the bin-by-bin correction is due to the parameterisation of the rapidity andcentrality dependence of C Z described in Eq. (2) and it stems primarily from the statistical uncertainty ofthe MC data set. To estimate uncertainties associated with these assumptions the parameters of the function G ( y , Σ E FCalT ) are varied by the errors of the parameters of the parabolic fit including covariance betweenthe parameters. The data are corrected with these variations, and the difference between these results andthe standard correction are taken as an estimate of the systematic uncertainty. In the muon channel theuncertainty associated with this source ranges from 0.4% to 1.4% in rapidity bins and is constant at ∼ ∼ ∼
1% formost centrality intervals, although in the most peripheral bin this contribution rises to ∼ (cid:104) T AA (cid:105) and (cid:104) N part (cid:105) )listed in Table 1 range from about 1% in central collisions to about 12% in peripheral collisions. These aretreated as fully correlated between the channels. Finally, the total uncertainty for the pp measurement [15]used for the R AA calculation is 2.3%. The rapidity distributions of the Z boson yield for the muon and electron decay channels, normalised bythe number of MB events and mean nuclear thickness function (cid:104) T AA (cid:105) , are shown in the upper-left panel of11 [ pb ] y / d Z N d - æ AA T Æ - v t N ATLAS -1 Pb+Pb, 0.49 nb=5.02 TeV NN s <116 GeV ll m l T p |<2.5 l h | ll fi Z mm fi Z ee fi Z | y | C o m b i ned C hanne l [ pb ] Z N - æ AA T Æ - v t N ATLAS -1 Pb+Pb, 0.49 nb=5.02 TeV NN s <116 GeV ll m l T p |<2.5 l h | ll fi Z mm fi Z ee fi Z error scaled up by 3 æ part N Æ æ part N Æ C o m b i ned C hanne l Figure 2: Normalised Z boson yields measured in the muon and electron decay channels together with the combinedyield as a function of (left) rapidity and (right) (cid:104) N part (cid:105) . Lower panels show the ratio of individual channels to thecombined result. The error bars in the upper panels show the total uncertainty for muons and electrons and thestatistical uncertainty for the combined data. In the lower panels, the error bars show the statistical uncertainty. Theshaded band (left) and boxes (right) show the systematic uncertainty of the combined result in both panels. Thewidth of each error box in the right panel corresponds to the systematic uncertainty of (cid:104) N part (cid:105) , scaled by a factor ofthree for clarity. Figure 2. The right panel of the figure shows the (cid:104) N part (cid:105) dependence of the normalised Z boson yield in thefiducial acceptance where the systematic uncertainties of the (cid:104) N part (cid:105) values are scaled by a factor of threefor clarity. The measurements performed in the two channels are combined using the Best Linear UnbiasedEstimate (BLUE) method [52], accounting for the correlations of the systematic uncertainties across thechannels and measurement bins. The combined result is shown in Figure 2 together with the combinedstatistical and systematic uncertainties. The level of agreement between the channels shown in the lowerpanels of the figure is quantified as χ / N dof = . / χ / N dof = . /
14 as afunction of centrality.The measured Z boson yields are compared with theoretical predictions obtained using a modified versionof DYNNLO 1.5 [53, 54] optimised for fast computations. The calculation is performed at O ( α S ) in QCDand at leading order in the EW theory, with parameters set according to the G µ scheme [55]. The inputparameters (the Fermi constant G F , the masses and widths of W and Z bosons, and the CKM matrixelements) are taken from Ref. [56]. The DYNNLO predictions are calculated using the free proton PDFset CT14 NLO [57] typically used to compare with the pp data and, additionally, the nuclear PDF setsnCTEQ15 NLO [58] and EPPS16 NLO [59], which are averaged over each Pb nucleus. In addition,the parton-level NLO prediction from the MCFM code [60], interfaced to the CT14 NLO PDF set, iscalculated. This takes into account the isospin effect, due to different partonic compositions of protonsand neutrons in the Pb nuclei, which is neglected in the DYNNLO calculations. The renormalisation andfactorisation scales, respectively denoted by µ r and µ f , are set to the value of lepton pair invariant mass.The uncertainties of these predictions are derived as follows. The effects of PDF uncertainties are evaluatedfrom the variations corresponding to each NLO PDF set. Uncertainties due to the scales are defined by theenvelope of the variations obtained by changing µ r and µ f by a factor of two from their nominal valuesand imposing 0 . ≤ µ r / µ f ≤
2. The uncertainty induced by the strong coupling constant is estimated byvarying α S by ± .
001 around the central value of α S ( m Z ) = . [ pb ] y / d Z N d - æ AA T Æ - v t N ATLAS -1 Pb+Pb, 0.49 nb=5.02 TeV NN s <116 GeV ll m l T p |<2.5 l h | - l + l fi Z CT14 NLO (Pb+Pb isospin)EPPS16 NLOnCTEQ15 NLO | y | D a t a T heo r y | Z |y AA R ATLAS -1 =5.02 TeV, 0.49 nb NN s Pb+Pb, -1 =5.02 TeV, 25 pb s , pp - l + l fi Z CT14 NLO (Pb+Pb isospin)EPPS16 NLOnCTEQ15 NLO <116 GeV ll m l T p |<2.5 l h | - l + l fi Z CT14 NLO (Pb+Pb isospin)EPPS16 NLOnCTEQ15 NLO | y | D a t a T heo r y Figure 3: The upper panels show the rapidity dependence of (left) the normalised Z boson yields and (right) of the R AA compared with theoretical predictions. The lower panels show the ratio of the theoretical predictions to thedata. The expected contribution of the isospin effect to the R AA is shown in the upper-right panel by the dashedline. The error bars on the data points indicate the statistical uncertainties and the shaded boxes show the systematicuncertainties. The error bars on predictions show the theoretical uncertainty. The points corresponding to nuclearPDF predictions are shifted horizontally relative to the bin centre for clarity. the effect of these variations is estimated by comparing the CT14nlo_as_0117 and CT14nlo_as_0119 PDFsets [57] to CT14 NLO. Imperfect knowledge of the proton PDF and the scale variations are the maincontributions to the total theory uncertainties. In calculating the R AA predictions, only the nuclear PDFuncertainties contribute since the CT14 NLO uncertainties cancel.In Figure 3 the normalised Z boson yield is compared between the combined measurement and thetheoretical predictions calculated with the CT14, nCTEQ15 and EPPS16 NLO PDF sets, with uncertaintiesassigned as previously described. All calculations lie 1–3 σ below the data in all rapidity intervals,integrated over event centrality. Calculations using nuclear PDF sets deviate from the data more stronglythan calculations based only on the CT14 NLO PDF set. A similar observation was made with the pp collision system [15] where systematic deviations from the measured values are observed for calculationsmade at the NNLO. When comparing the measured R AA with calculations, shown in the right panel ofFigure 3, residual deviations from the data are observed. The trend observed in data is consistent with theisospin effect only, expected from the different valence quark content of protons and neutrons in the Pbnucleus, shown in the upper-right panel of Figure 3 by the dashed line.Figure 4 shows the normalised Z boson yield as a function of rapidity for three centrality intervals. Theresults are consistent with each other within their respective statistical uncertainties. The size of the currentdata sample precludes making a more definitive statement about any possible modification of the Z bosonrapidity distribution with centrality.Figure 5 shows the centrality dependence of the normalised Z boson yield and of R AA . The pointcorresponding to the pp cross section [15] is shown in the plot at N part =
2. The results are derived fromGlauber MC v2.4 and a newer version v3.2 following the same procedure as described in Ref. [6]. Theresults are found to be consistent with each other within experimental uncertainties. The new GlauberMC calculation [61] implements a more advanced treatment of the nuclear density profile and an updatedexperimental value of the nucleon–nucleon inelastic cross section. From these two updates, the former13 |y| [ pb ] y / d Z N d - æ AA T Æ - v t N - l + l fi Z Pb+Pb 0-10%Pb+Pb 10-30%Pb+Pb 30-100% y /d ppZ s dCT14 NLO (Pb+Pb isospin) ATLAS -1 Pb+Pb, 0.49 nb -1 , 25 pb pp =5.02 TeV s , NN s | y | AA R Figure 4: Normalised Z boson yield versus rapidity measured in three centrality intervals: peripheral 30–100% (bluecircles), mid-central 10–30% (green squares) and central 0–10% (red diamonds). The differential Z boson crosssections measured in pp collisions are shown by open circles [15]. The error bars on the data points indicate thestatistical uncertainties and the shaded boxes show the total systematic uncertainties. The lower panel shows the R AA and the contribution from the isospin effect calculated with CT14 NLO PDF (dashed line). The shaded boxes at unityindicate the combined uncertainty from the pp data added in quadrature to the T AA uncertainty. The points in eachcentrality interval are shifted horizontally relative to the bin centre for clarity. æ part N Æ [ pb ] Z N - æ AA T Æ - v t N Glauber v2.4Glauber v3.2
Zpp s ATLAS -1 Pb+Pb, 0.49 nb -1 , 25 pb pp =5.02 TeV s , NN s æ part N Æ AA R MC isospinMC isospin, Glauber v3.2 error scaled up by 3 æ part N Æ Figure 5: The upper panel shows the normalised Z boson yield as a function of (cid:104) N part (cid:105) . The integrated fiducialcross section measured in the pp system is shown at N part = pp data. The figureshows the results calculated with Glauber MC v2.4 [24] and v3.2 [61]. The dashed and the full line indicate CT14NLO PDF calculations that account for isospin effects for the two Glauber MC versions. The width of the error boxfor each centrality interval corresponds to the systematic uncertainty in (cid:104) N part (cid:105) , scaled up by a factor of three forclarity.
100 200 300 400 æ part N Æ W / Z R ATLAS -1 Pb+Pb, 0.49 nb -1 , 25 pb pp =5.02 TeV s , NN s (isospin corrected) pp Pb+Pb /Z + W /Z - W /Z + W /Z - W Figure 6: Ratios of W + (circles) and W − (squares) yields measured in the same data set [6] to the yields of Z bosonsversus (cid:104) N part (cid:105) compared with the ratios measured in pp data [15] (shaded bands) scaled by isospin factors obtainedfrom the CT14 NLO PDF calculation. The error bars on the data points indicate the statistical uncertainties and theshaded boxes show the total systematic uncertainties. directly affects the normalised Z boson yield derived in this analysis while the updated cross section valuehas no appreciable effect. The new model also leads to a set of reduced systematic uncertainties comparedwith the previous version.In the estimation of the isospin effect contribution shown with dashed and full lines in Figure 5, the GlauberMC v3.2 model accounts for the slightly larger radius of the neutron distribution compared to the protonsin the Pb nucleus, often called the neutron skin effect. However, due to the weak dependence of Z bosonproduction on the isospin content of the colliding baryons, the predictions of the two Glauber MC versionsgive essentially the same result.The normalised yields are consistent with the pp cross section at all measured centralities and show only aweak dependence on N part . The values of R AA , shown in the lower panel, are consistent with unity withinthe total uncertainty. When the isospin effect is taken into account as shown with the dashed line, the modelseems to agree better with the data at low N part values rather than at high values. To quantify the dependenceof R AA on N part , the data are fit to a linear function. Including statistical and systematic uncertainties thedecrease in the R AA value between the most-peripheral (80–100%) and most-central (0–2%) centralityintervals is found to be ( ± ) % and ( ± ) % for Glauber MC v2.4 and v3.2, respectively.The Z boson measurement is used to compare the N part dependence of W [6] and Z boson productionby calculating their yield ratios as shown in Figure 6, where the uncertainties of the two measurementsare conservatively treated as uncorrelated. The data points are compared with the ratio measured in pp collisions [15] that is scaled by the isospin factors calculated using the CT14 NLO PDF set. Themeasurements for both channels are found to be consistent with the scaled pp measurement and show aconstant behaviour as a function of centrality.The trend of the points shown in Figure 5 for Z bosons is different from the trend observed by the ALICECollaboration in the measurements with charged hadrons with high transverse momentum [62]. It wasrecently shown in Ref. [63], that the R AA in peripheral nucleus–nucleus collisions can deviate from unitydue to a biased classification of the event geometry for events containing a hard process. In that analysis,the value of R AA without any nuclear effects was determined by using the HG-Pythia model [63], which15
20 40 60 80 100 Centrality [%]0.40.60.811.21.41.6 AA R ATLAS -1 =5.02 TeV, 0.49 nb NN s Pb+Pb, -1 =5.02 TeV, 25 pb s , pp Data HG-Pythia (isospin corrected) - W Z + W - W Z + W Figure 7: Nuclear modification factor R AA in centrality intervals compared with the HG-Pythia model [63] scaledby the isospin factors obtained from the CT14 NLO PDF calculation. The error bars on the data points indicate thestatistical uncertainties and the shaded boxes show the total systematic uncertainties. The model accounts for a biasedclassification of the event geometry for events containing a hard process. The bins are ordered in centrality percentile,starting from central events on the left towards more peripheral on the right. The Z boson measurement extends tothe most peripheral 80–100% centrality interval. The comparison is shown in the 0–80% centrality interval wherethe different smearing of the ATLAS centrality estimator ( Σ E FCalT ) is found to have a negligible effect. can create an ensemble of events where the Hijing [64] event generator is used to determine the number ofhard sub-interactions for each event, and the particle production is determined solely by superimposing acorresponding number of Pythia 6.4 [40] events. The model is able to qualitatively explain the ALICEmeasurement in the peripheral region.Figure 7 shows the R AA for W ± [6] and Z bosons compared with the HG-Pythia model. To comparethe model with the measurements of massive electroweak bosons the results are corrected for the isospineffect using the CT14 NLO PDF. All three data sets show trends that are consistent between the species,but that differ from their corresponding model predictions. This suggests that the apparent suppressionmechanism [63] that explains the ALICE data [62] for the yields of high- p T charged particles does nothave the same effect on the yields of massive electroweak bosons. The Z boson production yield per minimum-bias collision, scaled by the mean nuclear thickness function (cid:104) T AA (cid:105) is reported in Pb+Pb collisions at a nucleon–nucleon centre-of-mass energy √ s NN = .
02 TeV. Themeasurement is based on data taken by the ATLAS detector at the LHC corresponding to an integratedluminosity of 0.49 nb − . Normalised yields are reported in the electron and muon decay channels,differentially in rapidity and collision centrality in the mass window 66 < m (cid:96)(cid:96) <
116 GeV. The fiducialregion is defined using the lepton kinematics and detector acceptance. The electron channel and muonchannel results are found to agree within the measurement precision and are combined for the final result.The normalised Z boson yields measured in Pb+Pb collisions are 1–3 σ higher than NLO pQCD predictionswith both free and nuclear PDF sets, where the difference increases towards forward Z boson rapidity.The nuclear modification factor is measured differentially as a function of Z boson rapidity and event16entrality. It is found to be consistent with unity in centrality and to agree with the prediction based onthe CT14 PDF set that takes isospin into account. This behaviour is also consistent with the ATLASmeasurement performed with W bosons. The yield ratios W / Z are found to be constant as a function ofcentrality within the uncertainties of the measurements. Unlike high- p T charged hadrons measured by theALICE Collaboration, W and Z bosons show no indication of yield suppression in peripheral collisions. Acknowledgements
We thank CERN for the very successful operation of the LHC, as well as the support staff from ourinstitutions without whom ATLAS could not be operated efficiently.We acknowledge the support of ANPCyT, Argentina; YerPhI, Armenia; ARC, Australia; BMWFWand FWF, Austria; ANAS, Azerbaijan; SSTC, Belarus; CNPq and FAPESP, Brazil; NSERC, NRC andCFI, Canada; CERN; CONICYT, Chile; CAS, MOST and NSFC, China; COLCIENCIAS, Colombia;MSMT CR, MPO CR and VSC CR, Czech Republic; DNRF and DNSRC, Denmark; IN2P3-CNRS,CEA-DRF/IRFU, France; SRNSFG, Georgia; BMBF, HGF, and MPG, Germany; GSRT, Greece; RGC,Hong Kong SAR, China; ISF and Benoziyo Center, Israel; INFN, Italy; MEXT and JSPS, Japan; CNRST,Morocco; NWO, Netherlands; RCN, Norway; MNiSW and NCN, Poland; FCT, Portugal; MNE/IFA,Romania; MES of Russia and NRC KI, Russian Federation; JINR; MESTD, Serbia; MSSR, Slovakia;ARRS and MIZŠ, Slovenia; DST/NRF, South Africa; MINECO, Spain; SRC and Wallenberg Foundation,Sweden; SERI, SNSF and Cantons of Bern and Geneva, Switzerland; MOST, Taiwan; TAEK, Turkey;STFC, United Kingdom; DOE and NSF, United States of America. In addition, individual groups andmembers have received support from BCKDF, CANARIE, CRC and Compute Canada, Canada; COST,ERC, ERDF, Horizon 2020, and Marie Skłodowska-Curie Actions, European Union; Investissements d’Avenir Labex and Idex, ANR, France; DFG and AvH Foundation, Germany; Herakleitos, Thales andAristeia programmes co-financed by EU-ESF and the Greek NSRF, Greece; BSF-NSF and GIF, Israel;CERCA Programme Generalitat de Catalunya, Spain; The Royal Society and Leverhulme Trust, UnitedKingdom.The crucial computing support from all WLCG partners is acknowledged gratefully, in particular fromCERN, the ATLAS Tier-1 facilities at TRIUMF (Canada), NDGF (Denmark, Norway, Sweden), CC-IN2P3(France), KIT/GridKA (Germany), INFN-CNAF (Italy), NL-T1 (Netherlands), PIC (Spain), ASGC(Taiwan), RAL (UK) and BNL (USA), the Tier-2 facilities worldwide and large non-WLCG resourceproviders. Major contributors of computing resources are listed in Ref. [65].
References [1] ATLAS Collaboration,
Measurement of Z boson Production in Pb+Pb Collisions at √ s N N = . TeV with the ATLAS Detector , Phys. Rev. Lett. (2013) 022301, arXiv: .[2] ATLAS Collaboration,
Measurement of the production and lepton charge asymmetry of W bosonsin Pb+Pb collisions at √ s N N = . TeV with the ATLAS detector , Eur. Phys. J. C (2015) 23,arXiv: .[3] CMS Collaboration, Study of Z Boson Production in PbPb Collisions at √ s N N = 2.76 TeV , Phys.Rev. Lett. (2011) 212301, arXiv: .174] CMS Collaboration,
Study of Z production in PbPb and pp collisions at √ s NN = . TeV in thedimuon and dielectron decay channels , JHEP (2015) 022, arXiv: .[5] CMS Collaboration, Study of W boson production in PbPb and pp collisions at √ s N N = . TeV ,Phys. Lett. B (2012) 66, arXiv: .[6] ATLAS Collaboration,
Measurement of W ± boson production in Pb+Pb collisions at √ s NN = . TeV with the ATLAS detector , (2019), arXiv: .[7] ATLAS Collaboration,
Centrality, rapidity and transverse momentum dependence of isolated promptphoton production in lead-lead collisions at √ s NN = . TeV measured with the ATLAS detector ,Phys. Rev. C (2016) 034914, arXiv: .[8] CMS Collaboration, Measurement of isolated photon production in pp and PbPb collisions at √ s N N = . TeV , Phys. Lett. B (2012) 256, arXiv: .[9] ALICE Collaboration,
Measurement of Z -boson production at large rapidities in Pb-Pb collisionsat √ s NN = . TeV , Phys. Lett. B (2018) 372, arXiv: .[10] LHCb Collaboration,
Observation of Z production in proton-lead collisions at LHCb , JHEP (2014) 030, arXiv: .[11] ATLAS Collaboration, Z boson production in p + Pb collisions at √ s N N = . TeV measured withthe ATLAS detector , Phys. Rev. C (2015) 044915, arXiv: .[12] CMS Collaboration, Study of Z boson production in pPb collisions at √ sN N =5.02TeV , Phys. Lett. B759 (2016) 36, arXiv: .[13] ALICE Collaboration,
W and Z boson production in p-Pb collisions at √ s NN = 5.02 TeV , JHEP (2017) 077, arXiv: .[14] CMS Collaboration, Observation of nuclear modifications in W ± boson production in pPb collisionsat √ s NN = , (2019), arXiv: .[15] ATLAS Collaboration, Measurements of W and Z boson production in pp collisions at √ s = . TeV with the ATLAS detector , Eur. Phys. J. C (2019) 128, arXiv: ,Erratum: Eur. Phys. J. C (2019) 374.[16] ATLAS Collaboration, The ATLAS Experiment at the CERN Large Hadron Collider , JINST (2008)S08003.[17] ATLAS Collaboration, ATLAS Insertable B-Layer Technical Design Report , ATLAS-TDR-19, 2010,url: https://cds.cern.ch/record/1291633 , Addendum: ATLAS-TDR-19-ADD-1, 2012,url: https://cds.cern.ch/record/1451888 .[18] B. Abbott et al.,
Production and integration of the ATLAS Insertable B-Layer , JINST (2018)T05008, arXiv: .[19] ATLAS Collaboration, Performance of the ATLAS trigger system in 2015 , Eur. Phys. J. C (2017) 317, arXiv: .[20] ATLAS Collaboration, Performance of electron and photon triggers in ATLAS during LHC Run 2 ,(2019), arXiv: .[21] ATLAS Collaboration,
Measurement of the jet radius and transverse momentum dependence ofinclusive jet suppression in lead-lead collisions at √ s N N = 2.76 TeV with the ATLAS detector , Phys.Lett. B (2013) 220, arXiv: .1822] ATLAS Collaboration,
Muon reconstruction performance of the ATLAS detector in proton–protoncollision data at √ s =13 TeV , Eur. Phys. J. C (2016) 292, arXiv: .[23] ATLAS Collaboration, Electron reconstruction and identification in the ATLAS experiment usingthe 2015 and 2016 LHC proton-proton collision data at √ s = 13 TeV , Eur. Phys. J. C (2019) 639,arXiv: .[24] M. L. Miller, K. Reygers, S. J. Sanders and P. Steinberg, Glauber Modeling in High-Energy NuclearCollisions , Ann. Rev. Nucl. Part. Sci. (2007) 205, arXiv: nucl-ex/0701025 [nucl-ex] .[25] ATLAS Collaboration, Prompt and non-prompt J / ψ and ψ ( ) suppression at high transversemomentum in .
02 TeV
Pb+Pb collisions with the ATLAS experiment , Eur. Phys. J. C (2018) 762,arXiv: .[26] ATLAS Collaboration, Measurement of photon–jet transverse momentum correlations in 5.02TeV Pb+Pb and pp collisions with ATLAS , Phys. Lett. B (2019) 167, arXiv: .[27] S. Agostinelli et al., GEANT4 - a simulation toolkit , Nucl. Instrum. Meth. A (2003) 250.[28] ATLAS Collaboration,
The ATLAS Simulation Infrastructure , Eur. Phys. J. C (2010) 823, arXiv: .[29] P. Nason, A New method for combining NLO QCD with shower Monte Carlo algorithms , JHEP (2004) 040, arXiv: hep-ph/0409146 [hep-ph] .[30] S. Frixione, P. Nason and C. Oleari, Matching NLO QCD computations with Parton Showersimulations: the POWHEG method , JHEP (2007) 070, arXiv: .[31] S. Alioli, P. Nason, C. Oleari and E. Re, A general framework for implementing NLO calculationsin shower Monte Carlo programs: the POWHEG BOX , JHEP (2010) 043, arXiv: .[32] S. Alioli, P. Nason, C. Oleari and E. Re, NLO vector-boson production matched with shower inPOWHEG , JHEP (2008) 060, arXiv: .[33] T. Sjöstrand, S. Mrenna and P. Z. Skands, A brief introduction to PYTHIA 8.1 , Comput. Phys.Commun. (2008) 852, arXiv: .[34] J. Gao et al.,
CT10 next-to-next-to-leading order global analysis of QCD , Phys. Rev. D (2014) 033009, arXiv: .[35] J. Pumplin et al., New generation of parton distributions with uncertainties from global QCDanalysis , JHEP (2002) 012, arXiv: hep-ph/0201195 [hep-ph] .[36] ATLAS Collaboration, Measurement of the Z / γ ∗ boson transverse momentum distribution in pp collisions at √ s = TeV with the ATLAS detector , JHEP (2014) 145, arXiv: .[37] N. Davidson, T. Przedzinski and Z. Was, PHOTOS interface in C++: Technical and physicsdocumentation , Comput. Phys. Commun. (2016) 86, arXiv: .[38] S. Frixione, P. Nason and G. Ridolfi,
A Positive-weight next-to-leading-order Monte Carlo for heavyflavour hadroproduction , JHEP (2007) 126, arXiv: .[39] H.-L. Lai et al., New parton distributions for collider physics , Phys. Rev. D (2010) 074024, arXiv: . 1940] T. Sjöstrand, S. Mrenna and P. Z. Skands, PYTHIA 6.4 physics and manual , JHEP (2006) 026,arXiv: hep-ph/0603175 [hep-ph] .[41] P. Z. Skands, Tuning Monte Carlo generators: The Perugia tunes , Phys. Rev. D (2010) 074018,arXiv: .[42] D. J. Lange, The EvtGen particle decay simulation package , Nucl. Instrum. Meth. A (2001) 152.[43] ATLAS Collaboration,
Electron and photon energy calibration with the ATLAS detector using2015-2016 LHC proton-proton collision data , JINST (2019) P03017, arXiv: .[44] C. A. Bertulani and G. Baur, Electromagnetic Processes in Relativistic Heavy Ion Collisions , Phys.Rept. (1988) 299.[45] F. Krauss, M. Greiner and G. Soff,
Photon and gluon induced processes in relativistic heavy ioncollisions , Prog. Part. Nucl. Phys. (1997) 503.[46] G. Baur, Coherent photon-photon interactions in very peripheral relativistic heavy ion collisions ,Eur. Phys. J. D (2009) 265, arXiv: .[47] V. P. Goncalves and M. V. T. Machado, Diffractive photoproduction of Z bosons in coherentinteractions at CERN-LHC , Eur. Phys. J. C (2008) 33, arXiv: , Erratum:Eur. Phys. J. C (2009) 351.[48] ATLAS Collaboration, Measurement of exclusive γγ → (cid:96) + (cid:96) − production in proton-proton collisionsat √ s = TeV with the ATLAS detector , Phys. Lett. B (2015) 242, arXiv: .[49] CMS Collaboration,
Exclusive photon-photon production of muon pairs in proton-proton collisionsat √ s = TeV , JHEP (2012) 052, arXiv: .[50] ATLAS Collaboration, Rapidity gap cross sections measured with the ATLAS detector in pp collisions at √ s = TeV , Eur. Phys. J.
C72 (2012) 1926, arXiv: .[51] ATLAS Collaboration,
Observation of Centrality-Dependent Acoplanarity for Muon Pairs Producedvia Two-Photon Scattering in Pb+Pb Collisions at √ s NN = . TeV with the ATLAS Detector , Phys.Rev. Lett. (2018) 212301, arXiv: .[52] A. Valassi,
Combining correlated measurements of several different physical quantities , Nucl.Instrum. Meth. A (2003) 391.[53] S. Catani and M. Grazzini,
Next-to-Next-to-Leading Order Subtraction Formalism in HadronCollisions and its Application to Higgs Boson Production at the Large Hadron Collider , Phys. Rev.Lett. (2007) 222002, arXiv: hep-ph/0703012 [hep-ph] .[54] S. Catani, L. Cieri, G. Ferrera, D. de Florian and M. Grazzini, Vector Boson Production at HadronColliders: A Fully Exclusive QCD Calculation at Next-to-Next-to-Leading Order , Phys. Rev. Lett. (2009) 082001, arXiv: .[55] W. F. L. Hollik,
Radiative Corrections in the Standard Model and Their Rôle for Precision Tests ofthe Electroweak Theory , Fortsch. Phys. (1990) 165.[56] Particle Data Group, K. A. Olive et al., Review of Particle Physics , Chin. Phys. C (2014) 090001.[57] S. Dulat et al., New parton distribution functions from a global analysis of quantum chromodynamics ,Phys. Rev. D (2016) 033006, arXiv: .2058] K. Kovarik et al., nCTEQ15 - Global analysis of nuclear parton distributions with uncertainties inthe CTEQ framework , Phys. Rev. D (2016) 085037, arXiv: .[59] K. J. Eskola, P. Paakkinen, H. Paukkunen and C. A. Salgado, The EPPS16 nuclear PDFs , PoSDIS2017 (2018) 197, arXiv: .[60] J. M. Campbell, R. K. Ellis and W. T. Giele,
A multi-threaded version of MCFM , Eur. Phys. J. C (2015) 246, arXiv: .[61] C. Loizides, J. Kamin and D. d’Enterria, Improved Monte Carlo Glauber predictions at present andfuture nuclear colliders , Phys. Rev. C (2018) 054910, arXiv: , Erratum:Phys. Rev. C (2019) 019901.[62] ALICE Collaboration, Analysis of the apparent nuclear modification in peripheral Pb-Pb collisionsat 5.02 TeV , Phys. Lett. B (2019) 420, arXiv: .[63] C. Loizides and A. Morsch,
Absence of jet quenching in peripheral nucleus–nucleus collisions , Phys.Lett. B (2017) 408, arXiv: .[64] X.-N. Wang and M. Gyulassy,
HIJING: A Monte Carlo model for multiple jet production in p p, p Aand A A collisions , Phys. Rev. D (1991) 3501.[65] ATLAS Collaboration, ATLAS Computing Acknowledgements , ATL-GEN-PUB-2016-002, url: https://cds.cern.ch/record/2202407 .21 he ATLAS Collaboration
G. Aad , B. Abbott , D.C. Abbott , A. Abed Abud , K. Abeling , D.K. Abhayasinghe ,S.H. Abidi , O.S. AbouZeid , N.L. Abraham , H. Abramowicz , H. Abreu , Y. Abulaiti ,B.S. Acharya , B. Achkar , S. Adachi , L. Adam , C. Adam Bourdarios , L. Adamczyk ,L. Adamek , J. Adelman , M. Adersberger , A. Adiguzel , S. Adorni , T. Adye ,A.A. Affolder , Y. Afik , C. Agapopoulou , M.N. Agaras , A. Aggarwal , C. Agheorghiesei ,J.A. Aguilar-Saavedra , F. Ahmadov , W.S. Ahmed , X. Ai , G. Aielli , S. Akatsuka ,T.P.A. Åkesson , E. Akilli , A.V. Akimov , K. Al Khoury , G.L. Alberghi , J. Albert ,M.J. Alconada Verzini , S. Alderweireldt , M. Aleksa , I.N. Aleksandrov , C. Alexa ,D. Alexandre , T. Alexopoulos , A. Alfonsi , F. Alfonsi , M. Alhroob , B. Ali ,G. Alimonti , J. Alison , S.P. Alkire , C. Allaire , B.M.M. Allbrooke , B.W. Allen ,P.P. Allport , A. Aloisio , A. Alonso , F. Alonso , C. Alpigiani , A.A. Alshehri ,M. Alvarez Estevez , D. Álvarez Piqueras , M.G. Alviggi , Y. Amaral Coutinho , A. Ambler ,L. Ambroz , C. Amelung , D. Amidei , S.P. Amor Dos Santos , S. Amoroso , C.S. Amrouche ,F. An , C. Anastopoulos , N. Andari , T. Andeen , C.F. Anders , J.K. Anders ,A. Andreazza , V. Andrei , C.R. Anelli , S. Angelidakis , A. Angerami ,A.V. Anisenkov , A. Annovi , C. Antel , M.T. Anthony , E. Antipov , M. Antonelli ,D.J.A. Antrim , F. Anulli , M. Aoki , J.A. Aparisi Pozo , L. Aperio Bella , G. Arabidze ,J.P. Araque , V. Araujo Ferraz , R. Araujo Pereira , C. Arcangeletti , A.T.H. Arce , F.A. Arduh ,J-F. Arguin , S. Argyropoulos , J.-H. Arling , A.J. Armbruster , A. Armstrong , O. Arnaez ,H. Arnold , Z.P. Arrubarrena Tame , A. Artamonov , G. Artoni , S. Artz , S. Asai ,N. Asbah , E.M. Asimakopoulou , L. Asquith , J. Assahsah , K. Assamagan , R. Astalos ,R.J. Atkin , M. Atkinson , N.B. Atlay , H. Atmani , K. Augsten , G. Avolio , R. Avramidou ,M.K. Ayoub , A.M. Azoulay , G. Azuelos , H. Bachacou , K. Bachas , M. Backes ,F. Backman , P. Bagnaia , M. Bahmani , H. Bahrasemani , A.J. Bailey , V.R. Bailey ,J.T. Baines , M. Bajic , C. Bakalis , O.K. Baker , P.J. Bakker , D. Bakshi Gupta , S. Balaji ,E.M. Baldin , P. Balek , F. Balli , W.K. Balunas , J. Balz , E. Banas , A. Bandyopadhyay ,Sw. Banerjee , A.A.E. Bannoura , L. Barak , W.M. Barbe , E.L. Barberio , D. Barberis ,M. Barbero , G. Barbour , T. Barillari , M-S. Barisits , J. Barkeloo , T. Barklow , R. Barnea ,S.L. Barnes , B.M. Barnett , R.M. Barnett , Z. Barnovska-Blenessy , A. Baroncelli , G. Barone ,A.J. Barr , L. Barranco Navarro , F. Barreiro , J. Barreiro Guimarães da Costa , S. Barsov ,R. Bartoldus , G. Bartolini , A.E. Barton , P. Bartos , A. Basalaev , A. Bassalat ,M.J. Basso , R.L. Bates , S. Batlamous , J.R. Batley , B. Batool , M. Battaglia ,M. Bauce , F. Bauer , K.T. Bauer , H.S. Bawa , J.B. Beacham , T. Beau ,P.H. Beauchemin , F. Becherer , P. Bechtle , H.C. Beck , H.P. Beck , K. Becker , M. Becker ,C. Becot , A. Beddall , A.J. Beddall , V.A. Bednyakov , M. Bedognetti , C.P. Bee ,T.A. Beermann , M. Begalli , M. Begel , A. Behera , J.K. Behr , F. Beisiegel , A.S. Bell ,G. Bella , L. Bellagamba , A. Bellerive , P. Bellos , K. Beloborodov , K. Belotskiy ,N.L. Belyaev , D. Benchekroun , N. Benekos , Y. Benhammou , D.P. Benjamin , M. Benoit ,J.R. Bensinger , S. Bentvelsen , L. Beresford , M. Beretta , D. Berge , E. Bergeaas Kuutmann ,N. Berger , B. Bergmann , L.J. Bergsten , J. Beringer , S. Berlendis , G. Bernardi , C. Bernius ,T. Berry , P. Berta , C. Bertella , I.A. Bertram , O. Bessidskaia Bylund , N. Besson ,A. Bethani , S. Bethke , A. Betti , A.J. Bevan , J. Beyer , D.S. Bhattacharya , P. Bhattarai ,R. Bi , R.M. Bianchi , O. Biebel , D. Biedermann , R. Bielski , K. Bierwagen ,N.V. Biesuz , M. Biglietti , T.R.V. Billoud , M. Bindi , A. Bingul , C. Bini ,22. Biondi , M. Birman , T. Bisanz , J.P. Biswal , D. Biswas , A. Bitadze , C. Bittrich ,K. Bjørke , K.M. Black , T. Blazek , I. Bloch , C. Blocker , A. Blue , U. Blumenschein ,G.J. Bobbink , V.S. Bobrovnikov , S.S. Bocchetta , A. Bocci , D. Boerner , D. Bogavac ,A.G. Bogdanchikov , C. Bohm , V. Boisvert , P. Bokan , T. Bold , A.S. Boldyrev ,A.E. Bolz , M. Bomben , M. Bona , J.S. Bonilla , M. Boonekamp , C.D. Booth ,H.M. Borecka-Bielska , A. Borisov , G. Borissov , J. Bortfeldt , D. Bortoletto , D. Boscherini ,M. Bosman , J.D. Bossio Sola , K. Bouaouda , J. Boudreau , E.V. Bouhova-Thacker ,D. Boumediene , S.K. Boutle , A. Boveia , J. Boyd , D. Boye , I.R. Boyko , A.J. Bozson ,J. Bracinik , N. Brahimi , G. Brandt , O. Brandt , F. Braren , B. Brau , J.E. Brau ,W.D. Breaden Madden , K. Brendlinger , L. Brenner , R. Brenner , S. Bressler , B. Brickwedde ,D.L. Briglin , D. Britton , D. Britzger , I. Brock , R. Brock , G. Brooijmans , W.K. Brooks ,E. Brost , J.H Broughton , P.A. Bruckman de Renstrom , D. Bruncko , A. Bruni , G. Bruni ,L.S. Bruni , S. Bruno , M. Bruschi , N. Bruscino , P. Bryant , L. Bryngemark , T. Buanes ,Q. Buat , P. Buchholz , A.G. Buckley , I.A. Budagov , M.K. Bugge , F. Bührer , O. Bulekov ,T.J. Burch , S. Burdin , C.D. Burgard , A.M. Burger , B. Burghgrave , J.T.P. Burr , C.D. Burton ,J.C. Burzynski , V. Büscher , E. Buschmann , P.J. Bussey , J.M. Butler , C.M. Buttar ,J.M. Butterworth , P. Butti , W. Buttinger , C.J. Buxo Vazquez , A. Buzatu ,A.R. Buzykaev , G. Cabras , S. Cabrera Urbán , D. Caforio , H. Cai , V.M.M. Cairo ,O. Cakir , N. Calace , P. Calafiura , A. Calandri , G. Calderini , P. Calfayan , G. Callea ,L.P. Caloba , S. Calvente Lopez , D. Calvet , S. Calvet , T.P. Calvet , M. Calvetti ,R. Camacho Toro , S. Camarda , D. Camarero Munoz , P. Camarri , D. Cameron ,R. Caminal Armadans , C. Camincher , S. Campana , M. Campanelli , A. Camplani ,A. Campoverde , V. Canale , A. Canesse , M. Cano Bret , J. Cantero , T. Cao , Y. Cao ,M.D.M. Capeans Garrido , M. Capua , R. Cardarelli , F. Cardillo , G. Carducci ,I. Carli , T. Carli , G. Carlino , B.T. Carlson , L. Carminati , R.M.D. Carney ,S. Caron , E. Carquin , S. Carrá , J.W.S. Carter , M.P. Casado , A.F. Casha , D.W. Casper ,R. Castelijn , F.L. Castillo , V. Castillo Gimenez , N.F. Castro , A. Catinaccio ,J.R. Catmore , A. Cattai , J. Caudron , V. Cavaliere , E. Cavallaro , M. Cavalli-Sforza ,V. Cavasinni , E. Celebi , F. Ceradini , L. Cerda Alberich , K. Cerny , A.S. Cerqueira ,A. Cerri , L. Cerrito , F. Cerutti , A. Cervelli , S.A. Cetin , Z. Chadi , D. Chakraborty ,S.K. Chan , W.S. Chan , W.Y. Chan , J.D. Chapman , B. Chargeishvili , D.G. Charlton ,T.P. Charman , C.C. Chau , S. Che , S. Chekanov , S.V. Chekulaev , G.A. Chelkov ,M.A. Chelstowska , B. Chen , C. Chen , C.H. Chen , H. Chen , J. Chen , J. Chen , S. Chen ,S.J. Chen , X. Chen , Y. Chen , Y-H. Chen , H.C. Cheng , H.J. Cheng , A. Cheplakov ,E. Cheremushkina , R. Cherkaoui El Moursli , E. Cheu , K. Cheung , T.J.A. Chevalérias ,L. Chevalier , V. Chiarella , G. Chiarelli , G. Chiodini , A.S. Chisholm , A. Chitan , I. Chiu ,Y.H. Chiu , M.V. Chizhov , K. Choi , A.R. Chomont , S. Chouridou , Y.S. Chow ,M.C. Chu , X. Chu , J. Chudoba , A.J. Chuinard , J.J. Chwastowski , L. Chytka , D. Cieri ,K.M. Ciesla , D. Cinca , V. Cindro , I.A. Cioară , A. Ciocio , F. Cirotto , Z.H. Citron ,M. Citterio , D.A. Ciubotaru , B.M. Ciungu , A. Clark , M.R. Clark , P.J. Clark ,C. Clement , Y. Coadou , M. Cobal , A. Coccaro , J. Cochran , H. Cohen ,A.E.C. Coimbra , L. Colasurdo , B. Cole , A.P. Colijn , J. Collot , P. Conde Muiño ,E. Coniavitis , S.H. Connell , I.A. Connelly , S. Constantinescu , F. Conventi ,A.M. Cooper-Sarkar , F. Cormier , K.J.R. Cormier , L.D. Corpe , M. Corradi ,E.E. Corrigan , F. Corriveau , A. Cortes-Gonzalez , M.J. Costa , F. Costanza , D. Costanzo ,G. Cowan , J.W. Cowley , J. Crane , K. Cranmer , S.J. Crawley , R.A. Creager ,S. Crépé-Renaudin , F. Crescioli , M. Cristinziani , V. Croft , G. Crosetti , A. Cueto ,23. Cuhadar Donszelmann , A.R. Cukierman , W.R. Cunningham , S. Czekierda , P. Czodrowski ,M.J. Da Cunha Sargedas De Sousa , J.V. Da Fonseca Pinto , C. Da Via , W. Dabrowski ,T. Dado , S. Dahbi , T. Dai , C. Dallapiccola , M. Dam , G. D’amen , V. D’Amico ,J. Damp , J.R. Dandoy , M.F. Daneri , N.P. Dang , N.S. Dann , M. Danninger , V. Dao ,G. Darbo , O. Dartsi , A. Dattagupta , T. Daubney , S. D’Auria , W. Davey , C. David ,T. Davidek , D.R. Davis , I. Dawson , K. De , R. De Asmundis , M. De Beurs ,S. De Castro , S. De Cecco , N. De Groot , P. de Jong , H. De la Torre , A. De Maria ,D. De Pedis , A. De Salvo , U. De Sanctis , M. De Santis , A. De Santo ,K. De Vasconcelos Corga , J.B. De Vivie De Regie , C. Debenedetti , D.V. Dedovich ,A.M. Deiana , M. Del Gaudio , J. Del Peso , Y. Delabat Diaz , D. Delgove , F. Deliot ,C.M. Delitzsch , M. Della Pietra , D. Della Volpe , A. Dell’Acqua , L. Dell’Asta ,M. Delmastro , C. Delporte , P.A. Delsart , D.A. DeMarco , S. Demers , M. Demichev ,G. Demontigny , S.P. Denisov , D. Denysiuk , L. D’Eramo , D. Derendarz , J.E. Derkaoui ,F. Derue , P. Dervan , K. Desch , C. Deterre , K. Dette , C. Deutsch , M.R. Devesa ,P.O. Deviveiros , A. Dewhurst , F.A. Di Bello , A. Di Ciaccio , L. Di Ciaccio ,W.K. Di Clemente , C. Di Donato , A. Di Girolamo , G. Di Gregorio , B. Di Micco ,R. Di Nardo , K.F. Di Petrillo , R. Di Sipio , D. Di Valentino , C. Diaconu , F.A. Dias ,T. Dias Do Vale , M.A. Diaz , J. Dickinson , E.B. Diehl , J. Dietrich , S. Díez Cornell ,A. Dimitrievska , W. Ding , J. Dingfelder , F. Dittus , F. Djama , T. Djobava , J.I. Djuvsland ,M.A.B. Do Vale , M. Dobre , D. Dodsworth , C. Doglioni , J. Dolejsi , Z. Dolezal ,M. Donadelli , B. Dong , J. Donini , A. D’onofrio , M. D’Onofrio , J. Dopke , A. Doria ,M.T. Dova , A.T. Doyle , E. Drechsler , E. Dreyer , T. Dreyer , A.S. Drobac , D. Du ,Y. Duan , F. Dubinin , M. Dubovsky , A. Dubreuil , E. Duchovni , G. Duckeck ,A. Ducourthial , O.A. Ducu , D. Duda , A. Dudarev , A.C. Dudder , E.M. Duffield ,L. Duflot , M. Dührssen , C. Dülsen , M. Dumancic , A.E. Dumitriu , A.K. Duncan ,M. Dunford , A. Duperrin , H. Duran Yildiz , M. Düren , A. Durglishvili , D. Duschinger ,B. Dutta , D. Duvnjak , G.I. Dyckes , M. Dyndal , S. Dysch , B.S. Dziedzic , K.M. Ecker ,R.C. Edgar , M.G. Eggleston , T. Eifert , G. Eigen , K. Einsweiler , T. Ekelof , H. El Jarrari ,M. El Kacimi , R. El Kosseifi , V. Ellajosyula , M. Ellert , F. Ellinghaus , A.A. Elliot ,N. Ellis , J. Elmsheuser , M. Elsing , D. Emeliyanov , A. Emerman , Y. Enari , M.B. Epland ,J. Erdmann , A. Ereditato , M. Errenst , M. Escalier , C. Escobar , O. Estrada Pastor ,E. Etzion , H. Evans , A. Ezhilov , F. Fabbri , L. Fabbri , V. Fabiani , G. Facini ,R.M. Faisca Rodrigues Pereira , R.M. Fakhrutdinov , S. Falciano , P.J. Falke , S. Falke ,J. Faltova , Y. Fang , Y. Fang , G. Fanourakis , M. Fanti , M. Faraj , A. Farbin ,A. Farilla , E.M. Farina , T. Farooque , S. Farrell , S.M. Farrington , P. Farthouat , F. Fassi ,P. Fassnacht , D. Fassouliotis , M. Faucci Giannelli , W.J. Fawcett , L. Fayard , O.L. Fedin ,W. Fedorko , M. Feickert , L. Feligioni , A. Fell , C. Feng , E.J. Feng , M. Feng ,M.J. Fenton , A.B. Fenyuk , J. Ferrando , A. Ferrante , A. Ferrari , P. Ferrari , R. Ferrari ,D.E. Ferreira de Lima , A. Ferrer , D. Ferrere , C. Ferretti , F. Fiedler , A. Filipčič ,F. Filthaut , K.D. Finelli , M.C.N. Fiolhais , L. Fiorini , F. Fischer , W.C. Fisher ,I. Fleck , P. Fleischmann , R.R.M. Fletcher , T. Flick , B.M. Flierl , L. Flores ,L.R. Flores Castillo , F.M. Follega , N. Fomin , J.H. Foo , G.T. Forcolin , A. Formica ,F.A. Förster , A.C. Forti , A.G. Foster , M.G. Foti , D. Fournier , H. Fox , P. Francavilla ,S. Francescato , M. Franchini , S. Franchino , D. Francis , L. Franconi , M. Franklin ,A.N. Fray , P.M. Freeman , B. Freund , W.S. Freund , E.M. Freundlich , D.C. Frizzell ,D. Froidevaux , J.A. Frost , C. Fukunaga , E. Fullana Torregrosa , E. Fumagalli ,T. Fusayasu , J. Fuster , A. Gabrielli , A. Gabrielli , G.P. Gach , S. Gadatsch , P. Gadow ,24. Gagliardi , L.G. Gagnon , C. Galea , B. Galhardo , G.E. Gallardo , E.J. Gallas ,B.J. Gallop , G. Galster , R. Gamboa Goni , K.K. Gan , S. Ganguly , J. Gao , Y. Gao ,Y.S. Gao , C. García , J.E. García Navarro , J.A. García Pascual , C. Garcia-Argos ,M. Garcia-Sciveres , R.W. Gardner , N. Garelli , S. Gargiulo , V. Garonne , A. Gaudiello ,G. Gaudio , I.L. Gavrilenko , A. Gavrilyuk , C. Gay , G. Gaycken , E.N. Gazis ,A.A. Geanta , C.M. Gee , C.N.P. Gee , J. Geisen , M. Geisen , C. Gemme , M.H. Genest ,C. Geng , S. Gentile , S. George , T. Geralis , L.O. Gerlach , P. Gessinger-Befurt ,G. Gessner , S. Ghasemi , M. Ghasemi Bostanabad , A. Ghosh , A. Ghosh , B. Giacobbe ,S. Giagu , N. Giangiacomi , P. Giannetti , A. Giannini , G. Giannini , S.M. Gibson ,M. Gignac , D. Gillberg , G. Gilles , D.M. Gingrich , M.P. Giordani , F.M. Giorgi ,P.F. Giraud , G. Giugliarelli , D. Giugni , F. Giuli , S. Gkaitatzis , I. Gkialas ,E.L. Gkougkousis , P. Gkountoumis , L.K. Gladilin , C. Glasman , J. Glatzer , P.C.F. Glaysher ,A. Glazov , G.R. Gledhill , M. Goblirsch-Kolb , D. Godin , S. Goldfarb , T. Golling ,D. Golubkov , A. Gomes , R. Goncalves Gama , R. Gonçalo , G. Gonella ,L. Gonella , A. Gongadze , F. Gonnella , J.L. Gonski , S. González de la Hoz ,S. Gonzalez-Sevilla , G.R. Gonzalvo Rodriguez , L. Goossens , P.A. Gorbounov , H.A. Gordon ,B. Gorini , E. Gorini , A. Gorišek , A.T. Goshaw , M.I. Gostkin , C.A. Gottardo ,M. Gouighri , D. Goujdami , A.G. Goussiou , N. Govender , C. Goy , E. Gozani ,I. Grabowska-Bold , E.C. Graham , J. Gramling , E. Gramstad , S. Grancagnolo , M. Grandi ,V. Gratchev , P.M. Gravila , F.G. Gravili , C. Gray , H.M. Gray , C. Grefe , K. Gregersen ,I.M. Gregor , P. Grenier , K. Grevtsov , C. Grieco , N.A. Grieser , A.A. Grillo , K. Grimm ,S. Grinstein , J.-F. Grivaz , S. Groh , E. Gross , J. Grosse-Knetter , Z.J. Grout , C. Grud ,A. Grummer , L. Guan , W. Guan , J. Guenther , A. Guerguichon , J.G.R. Guerrero Rojas ,F. Guescini , D. Guest , R. Gugel , T. Guillemin , S. Guindon , U. Gul , J. Guo , W. Guo ,Y. Guo , Z. Guo , R. Gupta , S. Gurbuz , G. Gustavino , M. Guth , P. Gutierrez ,C. Gutschow , C. Guyot , C. Gwenlan , C.B. Gwilliam , A. Haas , C. Haber , H.K. Hadavand ,N. Haddad , A. Hadef , S. Hageböck , M. Haleem , J. Haley , G. Halladjian ,G.D. Hallewell , K. Hamacher , P. Hamal , K. Hamano , H. Hamdaoui , G.N. Hamity ,K. Han , L. Han , S. Han , Y.F. Han , K. Hanagaki , M. Hance , D.M. Handl ,B. Haney , R. Hankache , E. Hansen , J.B. Hansen , J.D. Hansen , M.C. Hansen , P.H. Hansen ,E.C. Hanson , K. Hara , T. Harenberg , S. Harkusha , P.F. Harrison , N.M. Hartmann ,Y. Hasegawa , A. Hasib , S. Hassani , S. Haug , R. Hauser , L.B. Havener , M. Havranek ,C.M. Hawkes , R.J. Hawkings , D. Hayden , C. Hayes , R.L. Hayes , C.P. Hays , J.M. Hays ,H.S. Hayward , S.J. Haywood , F. He , M.P. Heath , V. Hedberg , L. Heelan , S. Heer ,K.K. Heidegger , W.D. Heidorn , J. Heilman , S. Heim , T. Heim , B. Heinemann ,J.J. Heinrich , L. Heinrich , C. Heinz , J. Hejbal , L. Helary , A. Held , S. Hellesund ,C.M. Helling , S. Hellman , C. Helsens , R.C.W. Henderson , Y. Heng , S. Henkelmann ,A.M. Henriques Correia , G.H. Herbert , H. Herde , V. Herget , Y. Hernández Jiménez , H. Herr ,M.G. Herrmann , T. Herrmann , G. Herten , R. Hertenberger , L. Hervas , T.C. Herwig ,G.G. Hesketh , N.P. Hessey , A. Higashida , S. Higashino , E. Higón-Rodriguez ,K. Hildebrand , E. Hill , J.C. Hill , K.K. Hill , K.H. Hiller , S.J. Hillier , M. Hils , I. Hinchliffe ,F. Hinterkeuser , M. Hirose , S. Hirose , D. Hirschbuehl , B. Hiti , O. Hladik , D.R. Hlaluku ,X. Hoad , J. Hobbs , N. Hod , M.C. Hodgkinson , A. Hoecker , F. Hoenig , D. Hohn ,D. Hohov , T.R. Holmes , M. Holzbock , L.B.A.H Hommels , S. Honda , T.M. Hong ,J.C. Honig , A. Hönle , B.H. Hooberman , W.H. Hopkins , Y. Horii , P. Horn , L.A. Horyn ,S. Hou , A. Hoummada , J. Howarth , J. Hoya , M. Hrabovsky , J. Hrdinka , I. Hristova ,J. Hrivnac , A. Hrynevich , T. Hryn’ova , P.J. Hsu , S.-C. Hsu , Q. Hu , S. Hu , Y.F. Hu ,25.P. Huang , Y. Huang , Y. Huang , Z. Hubacek , F. Hubaut , M. Huebner , F. Huegging ,T.B. Huffman , M. Huhtinen , R.F.H. Hunter , P. Huo , A.M. Hupe , N. Huseynov ,J. Huston , J. Huth , R. Hyneman , S. Hyrych , G. Iacobucci , G. Iakovidis , I. Ibragimov ,L. Iconomidou-Fayard , Z. Idrissi , P. Iengo , R. Ignazzi , O. Igonkina , R. Iguchi ,T. Iizawa , Y. Ikegami , M. Ikeno , D. Iliadis , N. Ilic , F. Iltzsche , G. Introzzi ,M. Iodice , K. Iordanidou , V. Ippolito , M.F. Isacson , M. Ishino , W. Islam ,C. Issever , S. Istin , F. Ito , J.M. Iturbe Ponce , R. Iuppa , A. Ivina , H. Iwasaki ,J.M. Izen , V. Izzo , P. Jacka , P. Jackson , R.M. Jacobs , B.P. Jaeger , V. Jain , G. Jäkel ,K.B. Jakobi , K. Jakobs , T. Jakoubek , J. Jamieson , K.W. Janas , R. Jansky , J. Janssen ,M. Janus , P.A. Janus , G. Jarlskog , N. Javadov , T. Javůrek , M. Javurkova , F. Jeanneau ,L. Jeanty , J. Jejelava , A. Jelinskas , P. Jenni , J. Jeong , N. Jeong , S. Jézéquel , H. Ji ,J. Jia , H. Jiang , Y. Jiang , Z. Jiang , S. Jiggins , F.A. Jimenez Morales , J. Jimenez Pena ,S. Jin , A. Jinaru , O. Jinnouchi , H. Jivan , P. Johansson , K.A. Johns , C.A. Johnson ,K. Jon-And , R.W.L. Jones , S.D. Jones , S. Jones , T.J. Jones , J. Jongmanns , P.M. Jorge ,J. Jovicevic , X. Ju , J.J. Junggeburth , A. Juste Rozas , A. Kaczmarska , M. Kado ,H. Kagan , M. Kagan , A. Kahn , C. Kahra , T. Kaji , E. Kajomovitz , C.W. Kalderon ,A. Kaluza , A. Kamenshchikov , M. Kaneda , L. Kanjir , Y. Kano , V.A. Kantserov ,J. Kanzaki , L.S. Kaplan , D. Kar , K. Karava , M.J. Kareem , S.N. Karpov , Z.M. Karpova ,V. Kartvelishvili , A.N. Karyukhin , L. Kashif , R.D. Kass , A. Kastanas , C. Kato ,J. Katzy , K. Kawade , K. Kawagoe , T. Kawaguchi , T. Kawamoto , G. Kawamura , E.F. Kay ,V.F. Kazanin , R. Keeler , R. Kehoe , J.S. Keller , E. Kellermann , D. Kelsey ,J.J. Kempster , J. Kendrick , K.E. Kennedy , O. Kepka , S. Kersten , B.P. Kerševan ,S. Ketabchi Haghighat , M. Khader , F. Khalil-Zada , M. Khandoga , A. Khanov ,A.G. Kharlamov , T. Kharlamova , E.E. Khoda , A. Khodinov , T.J. Khoo ,E. Khramov , J. Khubua , S. Kido , M. Kiehn , C.R. Kilby , Y.K. Kim , N. Kimura ,O.M. Kind , B.T. King , D. Kirchmeier , J. Kirk , A.E. Kiryunin , T. Kishimoto ,D.P. Kisliuk , V. Kitali , O. Kivernyk , T. Klapdor-Kleingrothaus , M. Klassen , M.H. Klein ,M. Klein , U. Klein , K. Kleinknecht , P. Klimek , A. Klimentov , T. Klingl , T. Klioutchnikova ,F.F. Klitzner , P. Kluit , S. Kluth , E. Kneringer , E.B.F.G. Knoops , A. Knue , D. Kobayashi ,T. Kobayashi , M. Kobel , M. Kocian , P. Kodys , P.T. Koenig , T. Koffas , N.M. Köhler ,T. Koi , M. Kolb , I. Koletsou , T. Komarek , T. Kondo , N. Kondrashova , K. Köneke ,A.C. König , T. Kono , R. Konoplich , V. Konstantinides , N. Konstantinidis , B. Konya ,R. Kopeliansky , S. Koperny , K. Korcyl , K. Kordas , G. Koren , A. Korn , I. Korolkov ,E.V. Korolkova , N. Korotkova , O. Kortner , S. Kortner , T. Kosek , V.V. Kostyukhin ,A. Kotsokechagia , A. Kotwal , A. Koulouris , A. Kourkoumeli-Charalampidi ,C. Kourkoumelis , E. Kourlitis , V. Kouskoura , A.B. Kowalewska , R. Kowalewski , C. Kozakai ,W. Kozanecki , A.S. Kozhin , V.A. Kramarenko , G. Kramberger , D. Krasnopevtsev ,M.W. Krasny , A. Krasznahorkay , D. Krauss , J.A. Kremer , J. Kretzschmar , P. Krieger ,F. Krieter , A. Krishnan , K. Krizka , K. Kroeninger , H. Kroha , J. Kroll , J. Kroll ,K.S. Krowpman , J. Krstic , U. Kruchonak , H. Krüger , N. Krumnack , M.C. Kruse ,J.A. Krzysiak , T. Kubota , O. Kuchinskaia , S. Kuday , J.T. Kuechler , S. Kuehn , A. Kugel ,T. Kuhl , V. Kukhtin , R. Kukla , Y. Kulchitsky , S. Kuleshov , Y.P. Kulinich , M. Kuna ,T. Kunigo , A. Kupco , T. Kupfer , O. Kuprash , H. Kurashige , L.L. Kurchaninov ,Y.A. Kurochkin , A. Kurova , M.G. Kurth , E.S. Kuwertz , M. Kuze , A.K. Kvam ,J. Kvita , T. Kwan , A. La Rosa , L. La Rotonda , F. La Ruffa , C. Lacasta ,F. Lacava , D.P.J. Lack , H. Lacker , D. Lacour , E. Ladygin , R. Lafaye , B. Laforge ,T. Lagouri , S. Lai , S. Lammers , W. Lampl , C. Lampoudis , E. Lançon , U. Landgraf ,26.P.J. Landon , M.C. Lanfermann , V.S. Lang , J.C. Lange , R.J. Langenberg , A.J. Lankford ,F. Lanni , K. Lantzsch , A. Lanza , A. Lapertosa , S. Laplace , J.F. Laporte , T. Lari ,F. Lasagni Manghi , M. Lassnig , T.S. Lau , A. Laudrain , A. Laurier , M. Lavorgna ,S.D. Lawlor , M. Lazzaroni , B. Le , E. Le Guirriec , M. LeBlanc , T. LeCompte ,F. Ledroit-Guillon , A.C.A. Lee , C.A. Lee , G.R. Lee , L. Lee , S.C. Lee , S.J. Lee , S. Lee ,B. Lefebvre , H.P. Lefebvre , M. Lefebvre , F. Legger , C. Leggett , K. Lehmann ,N. Lehmann , G. Lehmann Miotto , W.A. Leight , A. Leisos , M.A.L. Leite , C.E. Leitgeb ,R. Leitner , D. Lellouch , K.J.C. Leney , T. Lenz , B. Lenzi , R. Leone , S. Leone ,C. Leonidopoulos , A. Leopold , G. Lerner , C. Leroy , R. Les , C.G. Lester , M. Levchenko ,J. Levêque , D. Levin , L.J. Levinson , D.J. Lewis , B. Li , B. Li , C-Q. Li , F. Li , H. Li ,H. Li , J. Li , K. Li , L. Li , M. Li , Q. Li , Q.Y. Li , S. Li , X. Li , Y. Li ,Z. Li , Z. Liang , B. Liberti , A. Liblong , K. Lie , C.Y. Lin , K. Lin , T.H. Lin ,R.A. Linck , J.H. Lindon , A.L. Lionti , E. Lipeles , A. Lipniacka , M. Lisovyi , T.M. Liss ,A. Lister , A.M. Litke , J.D. Little , B. Liu , B.L Liu , H.B. Liu , H. Liu , J.B. Liu ,J.K.K. Liu , K. Liu , M. Liu , P. Liu , Y. Liu , Y.L. Liu , Y.W. Liu , M. Livan ,A. Lleres , J. Llorente Merino , S.L. Lloyd , C.Y. Lo , F. Lo Sterzo , E.M. Lobodzinska ,P. Loch , S. Loffredo , T. Lohse , K. Lohwasser , M. Lokajicek , J.D. Long , R.E. Long ,L. Longo , K.A. Looper , J.A. Lopez , I. Lopez Paz , A. Lopez Solis , J. Lorenz ,N. Lorenzo Martinez , M. Losada , P.J. Lösel , A. Lösle , X. Lou , X. Lou , A. Lounis , J. Love ,P.A. Love , J.J. Lozano Bahilo , M. Lu , Y.J. Lu , H.J. Lubatti , C. Luci , A. Lucotte ,C. Luedtke , F. Luehring , I. Luise , L. Luminari , B. Lund-Jensen , M.S. Lutz , D. Lynn ,R. Lysak , E. Lytken , F. Lyu , V. Lyubushkin , T. Lyubushkina , H. Ma , L.L. Ma , Y. Ma ,G. Maccarrone , A. Macchiolo , C.M. Macdonald , J. Machado Miguens , D. Madaffari ,R. Madar , W.F. Mader , N. Madysa , J. Maeda , T. Maeno , M. Maerker , A.S. Maevskiy ,V. Magerl , N. Magini , D.J. Mahon , C. Maidantchik , T. Maier , A. Maio , K. Maj ,O. Majersky , S. Majewski , Y. Makida , N. Makovec , B. Malaescu , Pa. Malecki ,V.P. Maleev , F. Malek , U. Mallik , D. Malon , C. Malone , S. Maltezos , S. Malyukov ,J. Mamuzic , G. Mancini , I. Mandić , L. Manhaes de Andrade Filho , I.M. Maniatis ,J. Manjarres Ramos , K.H. Mankinen , A. Mann , A. Manousos , B. Mansoulie , I. Manthos ,S. Manzoni , A. Marantis , G. Marceca , L. Marchese , G. Marchiori , M. Marcisovsky ,L. Marcoccia , C. Marcon , C.A. Marin Tobon , M. Marjanovic , Z. Marshall ,M.U.F Martensson , S. Marti-Garcia , C.B. Martin , T.A. Martin , V.J. Martin ,B. Martin dit Latour , L. Martinelli , M. Martinez , V.I. Martinez Outschoorn ,S. Martin-Haugh , V.S. Martoiu , A.C. Martyniuk , A. Marzin , S.R. Maschek , L. Masetti ,T. Mashimo , R. Mashinistov , J. Masik , A.L. Maslennikov , L. Massa ,P. Massarotti , P. Mastrandrea , A. Mastroberardino , T. Masubuchi , D. Matakias ,A. Matic , P. Mättig , J. Maurer , B. Maček , D.A. Maximov , R. Mazini , I. Maznas ,S.M. Mazza , S.P. Mc Kee , T.G. McCarthy , W.P. McCormack , E.F. McDonald ,J.A. Mcfayden , G. Mchedlidze , M.A. McKay , K.D. McLean , S.J. McMahon ,P.C. McNamara , C.J. McNicol , R.A. McPherson , J.E. Mdhluli , Z.A. Meadows ,S. Meehan , T. Megy , S. Mehlhase , A. Mehta , T. Meideck , B. Meirose , D. Melini ,B.R. Mellado Garcia , J.D. Mellenthin , M. Melo , F. Meloni , A. Melzer , S.B. Menary ,E.D. Mendes Gouveia , L. Meng , X.T. Meng , S. Menke , E. Meoni , S. Mergelmeyer ,S.A.M. Merkt , C. Merlassino , P. Mermod , L. Merola , C. Meroni , O. Meshkov ,J.K.R. Meshreki , A. Messina , J. Metcalfe , A.S. Mete , C. Meyer , J. Meyer , J-P. Meyer ,H. Meyer Zu Theenhausen , F. Miano , M. Michetti , R.P. Middleton , L. Mijović ,G. Mikenberg , M. Mikestikova , M. Mikuž , H. Mildner , M. Milesi , A. Milic ,27.A. Millar , D.W. Miller , A. Milov , D.A. Milstead , R.A. Mina , A.A. Minaenko ,M. Miñano Moya , I.A. Minashvili , A.I. Mincer , B. Mindur , M. Mineev , Y. Minegishi ,L.M. Mir , A. Mirto , K.P. Mistry , T. Mitani , J. Mitrevski , V.A. Mitsou , M. Mittal ,O. Miu , A. Miucci , P.S. Miyagawa , A. Mizukami , J.U. Mjörnmark , T. Mkrtchyan ,M. Mlynarikova , T. Moa , K. Mochizuki , P. Mogg , S. Mohapatra , R. Moles-Valls ,M.C. Mondragon , K. Mönig , J. Monk , E. Monnier , A. Montalbano , J. Montejo Berlingen ,M. Montella , F. Monticelli , S. Monzani , N. Morange , D. Moreno , M. Moreno Llácer ,C. Moreno Martinez , P. Morettini , M. Morgenstern , S. Morgenstern , D. Mori , M. Morii ,M. Morinaga , V. Morisbak , A.K. Morley , G. Mornacchi , A.P. Morris , L. Morvaj ,P. Moschovakos , B. Moser , M. Mosidze , T. Moskalets , H.J. Moss , J. Moss ,E.J.W. Moyse , S. Muanza , J. Mueller , R.S.P. Mueller , D. Muenstermann , G.A. Mullier ,D.P. Mungo , J.L. Munoz Martinez , F.J. Munoz Sanchez , P. Murin , W.J. Murray ,A. Murrone , M. Muškinja , C. Mwewa , A.G. Myagkov , J. Myers , M. Myska ,B.P. Nachman , O. Nackenhorst , A.Nag Nag , K. Nagai , K. Nagano , Y. Nagasaka , M. Nagel ,J.L. Nagle , E. Nagy , A.M. Nairz , Y. Nakahama , K. Nakamura , T. Nakamura , I. Nakano ,H. Nanjo , F. Napolitano , R.F. Naranjo Garcia , R. Narayan , I. Naryshkin , T. Naumann ,G. Navarro , P.Y. Nechaeva , F. Nechansky , T.J. Neep , A. Negri , M. Negrini , C. Nellist ,M.E. Nelson , S. Nemecek , P. Nemethy , M. Nessi , M.S. Neubauer , M. Neumann ,P.R. Newman , Y.S. Ng , Y.W.Y. Ng , B. Ngair , H.D.N. Nguyen , T. Nguyen Manh ,E. Nibigira , R.B. Nickerson , R. Nicolaidou , D.S. Nielsen , J. Nielsen , N. Nikiforou ,V. Nikolaenko , I. Nikolic-Audit , K. Nikolopoulos , P. Nilsson , H.R. Nindhito , Y. Ninomiya ,A. Nisati , N. Nishu , R. Nisius , I. Nitsche , T. Nitta , T. Nobe , Y. Noguchi , I. Nomidis ,M.A. Nomura , M. Nordberg , N. Norjoharuddeen , T. Novak , O. Novgorodova , R. Novotny ,L. Nozka , K. Ntekas , E. Nurse , F.G. Oakham , H. Oberlack , J. Ocariz , A. Ochi ,I. Ochoa , J.P. Ochoa-Ricoux , K. O’Connor , S. Oda , S. Odaka , S. Oerdek , A. Ogrodnik ,A. Oh , S.H. Oh , C.C. Ohm , H. Oide , M.L. Ojeda , H. Okawa , Y. Okazaki ,Y. Okumura , T. Okuyama , A. Olariu , L.F. Oleiro Seabra , S.A. Olivares Pino ,D. Oliveira Damazio , J.L. Oliver , M.J.R. Olsson , A. Olszewski , J. Olszowska , D.C. O’Neil ,A.P. O’neill , A. Onofre , P.U.E. Onyisi , H. Oppen , M.J. Oreglia , G.E. Orellana ,D. Orestano , N. Orlando , R.S. Orr , V. O’Shea , R. Ospanov , G. Otero y Garzon ,H. Otono , P.S. Ott , M. Ouchrif , J. Ouellette , F. Ould-Saada , A. Ouraou , Q. Ouyang ,M. Owen , R.E. Owen , V.E. Ozcan , N. Ozturk , J. Pacalt , H.A. Pacey , K. Pachal ,A. Pacheco Pages , C. Padilla Aranda , S. Pagan Griso , M. Paganini , G. Palacino , S. Palazzo ,S. Palestini , M. Palka , D. Pallin , I. Panagoulias , C.E. Pandini , J.G. Panduro Vazquez ,P. Pani , G. Panizzo , L. Paolozzi , C. Papadatos , K. Papageorgiou , S. Parajuli ,A. Paramonov , D. Paredes Hernandez , S.R. Paredes Saenz , B. Parida , T.H. Park , A.J. Parker ,M.A. Parker , F. Parodi , E.W.P. Parrish , J.A. Parsons , U. Parzefall , L. Pascual Dominguez ,V.R. Pascuzzi , J.M.P. Pasner , F. Pasquali , E. Pasqualucci , S. Passaggio , F. Pastore ,P. Pasuwan , S. Pataraia , J.R. Pater , A. Pathak , T. Pauly , B. Pearson , M. Pedersen ,L. Pedraza Diaz , R. Pedro , T. Peiffer , S.V. Peleganchuk , O. Penc , H. Peng ,B.S. Peralva , M.M. Perego , A.P. Pereira Peixoto , D.V. Perepelitsa , F. Peri , L. Perini ,H. Pernegger , S. Perrella , K. Peters , R.F.Y. Peters , B.A. Petersen , T.C. Petersen ,E. Petit , A. Petridis , C. Petridou , P. Petroff , M. Petrov , F. Petrucci , M. Pettee ,N.E. Pettersson , K. Petukhova , A. Peyaud , R. Pezoa , L. Pezzotti , T. Pham ,F.H. Phillips , P.W. Phillips , M.W. Phipps , G. Piacquadio , E. Pianori , A. Picazio ,R.H. Pickles , R. Piegaia , D. Pietreanu , J.E. Pilcher , A.D. Pilkington , M. Pinamonti ,J.L. Pinfold , M. Pitt , L. Pizzimento , M.-A. Pleier , V. Pleskot , E. Plotnikova ,28. Podberezko , R. Poettgen , R. Poggi , L. Poggioli , I. Pogrebnyak , D. Pohl ,I. Pokharel , G. Polesello , A. Poley , A. Policicchio , R. Polifka , A. Polini , C.S. Pollard ,V. Polychronakos , D. Ponomarenko , L. Pontecorvo , S. Popa , G.A. Popeneciu , L. Portales ,D.M. Portillo Quintero , S. Pospisil , K. Potamianos , I.N. Potrap , C.J. Potter , H. Potti ,T. Poulsen , J. Poveda , T.D. Powell , G. Pownall , M.E. Pozo Astigarraga , P. Pralavorio ,S. Prell , D. Price , M. Primavera , S. Prince , M.L. Proffitt , N. Proklova , K. Prokofiev ,F. Prokoshin , S. Protopopescu , J. Proudfoot , M. Przybycien , D. Pudzha , A. Puri , P. Puzo ,J. Qian , Y. Qin , A. Quadt , M. Queitsch-Maitland , A. Qureshi , M. Racko , P. Rados ,F. Ragusa , G. Rahal , J.A. Raine , S. Rajagopalan , A. Ramirez Morales , K. Ran ,T. Rashid , S. Raspopov , D.M. Rauch , F. Rauscher , S. Rave , B. Ravina , I. Ravinovich ,J.H. Rawling , M. Raymond , A.L. Read , N.P. Readioff , M. Reale , D.M. Rebuzzi ,A. Redelbach , G. Redlinger , K. Reeves , L. Rehnisch , J. Reichert , D. Reikher , A. Reiss ,A. Rej , C. Rembser , M. Renda , M. Rescigno , S. Resconi , E.D. Resseguie , S. Rettie ,E. Reynolds , O.L. Rezanova , P. Reznicek , E. Ricci , R. Richter , S. Richter ,E. Richter-Was , O. Ricken , M. Ridel , P. Rieck , O. Rifki , M. Rijssenbeek , A. Rimoldi ,M. Rimoldi , L. Rinaldi , G. Ripellino , I. Riu , J.C. Rivera Vergara , F. Rizatdinova ,E. Rizvi , C. Rizzi , R.T. Roberts , S.H. Robertson , M. Robin , D. Robinson ,J.E.M. Robinson , C.M. Robles Gajardo , A. Robson , A. Rocchi , E. Rocco , C. Roda ,S. Rodriguez Bosca , A. Rodriguez Perez , D. Rodriguez Rodriguez , A.M. Rodríguez Vera ,S. Roe , O. Røhne , R. Röhrig , R.A. Rojas , C.P.A. Roland , J. Roloff , A. Romaniouk ,M. Romano , N. Rompotis , M. Ronzani , L. Roos , S. Rosati , K. Rosbach , G. Rosin ,B.J. Rosser , E. Rossi , E. Rossi , E. Rossi , L.P. Rossi , L. Rossini , R. Rosten ,M. Rotaru , J. Rothberg , D. Rousseau , G. Rovelli , A. Roy , D. Roy , A. Rozanov ,Y. Rozen , X. Ruan , F. Rühr , A. Ruiz-Martinez , A. Rummler , Z. Rurikova ,N.A. Rusakovich , H.L. Russell , L. Rustige , J.P. Rutherfoord , E.M. Rüttinger , M. Rybar ,G. Rybkin , E.B. Rye , A. Ryzhov , P. Sabatini , G. Sabato , S. Sacerdoti ,H.F-W. Sadrozinski , R. Sadykov , F. Safai Tehrani , B. Safarzadeh Samani , P. Saha , S. Saha ,M. Sahinsoy , A. Sahu , M. Saimpert , M. Saito , T. Saito , H. Sakamoto , A. Sakharov ,D. Salamani , G. Salamanna , J.E. Salazar Loyola , A. Salnikov , J. Salt , D. Salvatore ,F. Salvatore , A. Salvucci , A. Salzburger , J. Samarati , D. Sammel , D. Sampsonidis ,D. Sampsonidou , J. Sánchez , A. Sanchez Pineda , H. Sandaker , C.O. Sander ,I.G. Sanderswood , M. Sandhoff , C. Sandoval , D.P.C. Sankey , M. Sannino , Y. Sano ,A. Sansoni , C. Santoni , H. Santos , S.N. Santpur , A. Santra , A. Sapronov ,J.G. Saraiva , O. Sasaki , K. Sato , F. Sauerburger , E. Sauvan , P. Savard , N. Savic ,R. Sawada , C. Sawyer , L. Sawyer , C. Sbarra , A. Sbrizzi , T. Scanlon , J. Schaarschmidt ,P. Schacht , B.M. Schachtner , D. Schaefer , L. Schaefer , J. Schaeffer , S. Schaepe ,U. Schäfer , A.C. Schaffer , D. Schaile , R.D. Schamberger , N. Scharmberg ,V.A. Schegelsky , D. Scheirich , F. Schenck , M. Schernau , C. Schiavi , S. Schier ,L.K. Schildgen , Z.M. Schillaci , E.J. Schioppa , M. Schioppa , K.E. Schleicher , S. Schlenker ,K.R. Schmidt-Sommerfeld , K. Schmieden , C. Schmitt , S. Schmitt , S. Schmitz ,J.C. Schmoeckel , U. Schnoor , L. Schoeffel , A. Schoening , P.G. Scholer , E. Schopf ,M. Schott , J.F.P. Schouwenberg , J. Schovancova , S. Schramm , F. Schroeder , A. Schulte ,H-C. Schultz-Coulon , M. Schumacher , B.A. Schumm , Ph. Schune , A. Schwartzman ,T.A. Schwarz , Ph. Schwemling , R. Schwienhorst , A. Sciandra , G. Sciolla , M. Scodeggio ,M. Scornajenghi , F. Scuri , F. Scutti , L.M. Scyboz , C.D. Sebastiani , P. Seema ,S.C. Seidel , A. Seiden , B.D. Seidlitz , T. Seiss , J.M. Seixas , G. Sekhniaidze , K. Sekhon ,S.J. Sekula , N. Semprini-Cesari , S. Sen , C. Serfon , L. Serin , L. Serkin , M. Sessa ,29. Severini , T. Šfiligoj , F. Sforza , A. Sfyrla , E. Shabalina , J.D. Shahinian ,N.W. Shaikh , D. Shaked Renous , L.Y. Shan , J.T. Shank , M. Shapiro , A. Sharma ,A.S. Sharma , P.B. Shatalov , K. Shaw , S.M. Shaw , A. Shcherbakova , M. Shehade ,Y. Shen , N. Sherafati , A.D. Sherman , P. Sherwood , L. Shi , S. Shimizu , C.O. Shimmin ,Y. Shimogama , M. Shimojima , I.P.J. Shipsey , S. Shirabe , M. Shiyakova , J. Shlomi ,A. Shmeleva , M.J. Shochet , J. Shojaii , D.R. Shope , S. Shrestha , E.M. Shrif , E. Shulga ,P. Sicho , A.M. Sickles , P.E. Sidebo , E. Sideras Haddad , O. Sidiropoulou , A. Sidoti ,F. Siegert , Dj. Sijacki , M.Jr. Silva , M.V. Silva Oliveira , S.B. Silverstein , S. Simion ,E. Simioni , R. Simoniello , S. Simsek , P. Sinervo , V. Sinetckii , N.B. Sinev ,M. Sioli , I. Siral , S.Yu. Sivoklokov , J. Sjölin , E. Skorda , P. Skubic , M. Slawinska ,K. Sliwa , R. Slovak , V. Smakhtin , B.H. Smart , J. Smiesko , N. Smirnov ,S.Yu. Smirnov , Y. Smirnov , L.N. Smirnova , O. Smirnova , J.W. Smith , M. Smizanska ,K. Smolek , A. Smykiewicz , A.A. Snesarev , H.L. Snoek , I.M. Snyder , S. Snyder ,R. Sobie , A. Soffer , A. Søgaard , F. Sohns , C.A. Solans Sanchez , E.Yu. Soldatov ,U. Soldevila , A.A. Solodkov , A. Soloshenko , O.V. Solovyanov , V. Solovyev , P. Sommer ,H. Son , W. Song , W.Y. Song , A. Sopczak , F. Sopkova , C.L. Sotiropoulou ,S. Sottocornola , R. Soualah , A.M. Soukharev , D. South , S. Spagnolo ,M. Spalla , M. Spangenberg , F. Spanò , D. Sperlich , T.M. Spieker , R. Spighi , G. Spigo ,M. Spina , D.P. Spiteri , M. Spousta , A. Stabile , B.L. Stamas , R. Stamen ,M. Stamenkovic , E. Stanecka , B. Stanislaus , M.M. Stanitzki , M. Stankaityte , B. Stapf ,E.A. Starchenko , G.H. Stark , J. Stark , S.H. Stark , P. Staroba , P. Starovoitov , S. Stärz ,R. Staszewski , G. Stavropoulos , M. Stegler , P. Steinberg , A.L. Steinhebel , B. Stelzer ,H.J. Stelzer , O. Stelzer-Chilton , H. Stenzel , T.J. Stevenson , G.A. Stewart , M.C. Stockton ,G. Stoicea , M. Stolarski , S. Stonjek , A. Straessner , J. Strandberg , S. Strandberg ,M. Strauss , P. Strizenec , R. Ströhmer , D.M. Strom , R. Stroynowski , A. Strubig ,S.A. Stucci , B. Stugu , J. Stupak , N.A. Styles , D. Su , S. Suchek , V.V. Sulin ,M.J. Sullivan , D.M.S. Sultan , S. Sultansoy , T. Sumida , S. Sun , X. Sun , K. Suruliz ,C.J.E. Suster , M.R. Sutton , S. Suzuki , M. Svatos , M. Swiatlowski , S.P. Swift , T. Swirski ,A. Sydorenko , I. Sykora , M. Sykora , T. Sykora , D. Ta , K. Tackmann , J. Taenzer ,A. Taffard , R. Tafirout , H. Takai , R. Takashima , K. Takeda , T. Takeshita , E.P. Takeva ,Y. Takubo , M. Talby , A.A. Talyshev , N.M. Tamir , J. Tanaka , M. Tanaka ,R. Tanaka , S. Tapia Araya , S. Tapprogge , A. Tarek Abouelfadl Mohamed , S. Tarem ,K. Tariq , G. Tarna , G.F. Tartarelli , P. Tas , M. Tasevsky , T. Tashiro , E. Tassi ,A. Tavares Delgado , Y. Tayalati , A.J. Taylor , G.N. Taylor , W. Taylor , A.S. Tee ,R. Teixeira De Lima , P. Teixeira-Dias , H. Ten Kate , J.J. Teoh , S. Terada , K. Terashi ,J. Terron , S. Terzo , M. Testa , R.J. Teuscher , S.J. Thais , T. Theveneaux-Pelzer , F. Thiele ,D.W. Thomas , J.O. Thomas , J.P. Thomas , A.S. Thompson , P.D. Thompson , L.A. Thomsen ,E. Thomson , E.J. Thorpe , R.E. Ticse Torres , V.O. Tikhomirov , Yu.A. Tikhonov ,S. Timoshenko , P. Tipton , S. Tisserant , K. Todome , S. Todorova-Nova , S. Todt , J. Tojo ,S. Tokár , K. Tokushuku , E. Tolley , K.G. Tomiwa , M. Tomoto , L. Tompkins , B. Tong ,P. Tornambe , E. Torrence , H. Torres , E. Torró Pastor , C. Tosciri , J. Toth , D.R. Tovey ,A. Traeet , C.J. Treado , T. Trefzger , F. Tresoldi , A. Tricoli , I.M. Trigger ,S. Trincaz-Duvoid , W. Trischuk , B. Trocmé , A. Trofymov , C. Troncon , M. Trovatelli ,F. Trovato , L. Truong , M. Trzebinski , A. Trzupek , F. Tsai , J.C-L. Tseng ,P.V. Tsiareshka , A. Tsirigotis , V. Tsiskaridze , E.G. Tskhadadze , M. Tsopoulou ,I.I. Tsukerman , V. Tsulaia , S. Tsuno , D. Tsybychev , Y. Tu , A. Tudorache , V. Tudorache ,T.T. Tulbure , A.N. Tuna , S. Turchikhin , D. Turgeman , I. Turk Cakir , R.J. Turner ,30.T. Turra , P.M. Tuts , S. Tzamarias , E. Tzovara , G. Ucchielli , K. Uchida , I. Ueda ,M. Ughetto , F. Ukegawa , G. Unal , A. Undrus , G. Unel , F.C. Ungaro , Y. Unno ,K. Uno , J. Urban , P. Urquijo , G. Usai , Z. Uysal , V. Vacek , B. Vachon , K.O.H. Vadla ,A. Vaidya , C. Valderanis , E. Valdes Santurio , M. Valente , S. Valentinetti , A. Valero ,L. Valéry , R.A. Vallance , A. Vallier , J.A. Valls Ferrer , T.R. Van Daalen , P. Van Gemmeren ,I. Van Vulpen , M. Vanadia , W. Vandelli , E.R. Vandewall , A. Vaniachine ,D. Vannicola , R. Vari , E.W. Varnes , C. Varni , T. Varol , D. Varouchas ,K.E. Varvell , M.E. Vasile , G.A. Vasquez , J.G. Vasquez , F. Vazeille , D. Vazquez Furelos ,T. Vazquez Schroeder , J. Veatch , V. Vecchio , M.J. Veen , L.M. Veloce , F. Veloso ,S. Veneziano , A. Ventura , N. Venturi , A. Verbytskyi , V. Vercesi , M. Verducci ,C.M. Vergel Infante , C. Vergis , W. Verkerke , A.T. Vermeulen , J.C. Vermeulen ,M.C. Vetterli , N. Viaux Maira , M. Vicente Barreto Pinto , T. Vickey , O.E. Vickey Boeriu ,G.H.A. Viehhauser , L. Vigani , M. Villa , M. Villaplana Perez , E. Vilucchi ,M.G. Vincter , G.S. Virdee , A. Vishwakarma , C. Vittori , I. Vivarelli , M. Vogel ,P. Vokac , S.E. von Buddenbrock , E. Von Toerne , V. Vorobel , K. Vorobev , M. Vos ,J.H. Vossebeld , M. Vozak , N. Vranjes , M. Vranjes Milosavljevic , V. Vrba , M. Vreeswijk ,R. Vuillermet , I. Vukotic , P. Wagner , W. Wagner , J. Wagner-Kuhr , S. Wahdan ,H. Wahlberg , V.M. Walbrecht , J. Walder , R. Walker , S.D. Walker , W. Walkowiak ,V. Wallangen , A.M. Wang , C. Wang , C. Wang , F. Wang , H. Wang , H. Wang ,J. Wang , J. Wang , J. Wang , P. Wang , Q. Wang , R.-J. Wang , R. Wang , R. Wang ,S.M. Wang , W.T. Wang , W. Wang , W.X. Wang , Y. Wang , Z. Wang ,C. Wanotayaroj , A. Warburton , C.P. Ward , D.R. Wardrope , N. Warrack , A. Washbrook ,A.T. Watson , M.F. Watson , G. Watts , B.M. Waugh , A.F. Webb , S. Webb , C. Weber ,M.S. Weber , S.A. Weber , S.M. Weber , A.R. Weidberg , J. Weingarten , M. Weirich ,C. Weiser , P.S. Wells , T. Wenaus , T. Wengler , S. Wenig , N. Wermes , M.D. Werner ,M. Wessels , T.D. Weston , K. Whalen , N.L. Whallon , A.M. Wharton , A.S. White ,A. White , M.J. White , D. Whiteson , B.W. Whitmore , W. Wiedenmann , M. Wielers ,N. Wieseotte , C. Wiglesworth , L.A.M. Wiik-Fuchs , F. Wilk , H.G. Wilkens , L.J. Wilkins ,H.H. Williams , S. Williams , C. Willis , S. Willocq , J.A. Wilson , I. Wingerter-Seez ,E. Winkels , F. Winklmeier , O.J. Winston , B.T. Winter , M. Wittgen , M. Wobisch ,A. Wolf , T.M.H. Wolf , R. Wolff , R.W. Wölker , J. Wollrath , M.W. Wolter ,H. Wolters , V.W.S. Wong , N.L. Woods , S.D. Worm , B.K. Wosiek , K.W. Woźniak ,K. Wraight , S.L. Wu , X. Wu , Y. Wu , T.R. Wyatt , B.M. Wynne , S. Xella , Z. Xi ,L. Xia , X. Xiao , I. Xiotidis , D. Xu , H. Xu , L. Xu , T. Xu , W. Xu , Z. Xu , Z. Xu ,B. Yabsley , S. Yacoob , K. Yajima , D.P. Yallup , D. Yamaguchi , Y. Yamaguchi ,A. Yamamoto , M. Yamatani , T. Yamazaki , Y. Yamazaki , Z. Yan , H.J. Yang , H.T. Yang ,S. Yang , X. Yang , Y. Yang , W-M. Yao , Y.C. Yap , Y. Yasu , E. Yatsenko , J. Ye ,S. Ye , I. Yeletskikh , M.R. Yexley , E. Yigitbasi , K. Yorita , K. Yoshihara , C.J.S. Young ,C. Young , J. Yu , R. Yuan , X. Yue , S.P.Y. Yuen , M. Zaazoua , B. Zabinski , G. Zacharis ,E. Zaffaroni , J. Zahreddine , A.M. Zaitsev , T. Zakareishvili , N. Zakharchuk , S. Zambito ,D. Zanzi , D.R. Zaripovas , S.V. Zeißner , C. Zeitnitz , G. Zemaityte , J.C. Zeng , O. Zenin ,T. Ženiš , D. Zerwas , M. Zgubič , B. Zhang , D.F. Zhang , G. Zhang , H. Zhang ,J. Zhang , L. Zhang , L. Zhang , M. Zhang , R. Zhang , X. Zhang , Y. Zhang , Z. Zhang ,Z. Zhang , P. Zhao , Y. Zhao , Z. Zhao , A. Zhemchugov , Z. Zheng , D. Zhong , B. Zhou ,C. Zhou , M.S. Zhou , M. Zhou , N. Zhou , Y. Zhou , C.G. Zhu , C. Zhu , H.L. Zhu ,H. Zhu , J. Zhu , Y. Zhu , X. Zhuang , K. Zhukov , V. Zhulanov , D. Zieminska ,N.I. Zimine , S. Zimmermann , Z. Zinonos , M. Ziolkowski , L. Živković , G. Zobernig ,31. Zoccoli , K. Zoch , T.G. Zorbas , R. Zou , L. Zwalinski . Department of Physics, University of Adelaide, Adelaide; Australia. Physics Department, SUNY Albany, Albany NY; United States of America. Department of Physics, University of Alberta, Edmonton AB; Canada. ( a ) Department of Physics, Ankara University, Ankara; ( b ) Istanbul Aydin University, Istanbul; ( c ) Division ofPhysics, TOBB University of Economics and Technology, Ankara; Turkey. LAPP, Université Grenoble Alpes, Université Savoie Mont Blanc, CNRS/IN2P3, Annecy; France. High Energy Physics Division, Argonne National Laboratory, Argonne IL; United States of America. Department of Physics, University of Arizona, Tucson AZ; United States of America. Department of Physics, University of Texas at Arlington, Arlington TX; United States of America. Physics Department, National and Kapodistrian University of Athens, Athens; Greece. Physics Department, National Technical University of Athens, Zografou; Greece. Department of Physics, University of Texas at Austin, Austin TX; United States of America. ( a ) Bahcesehir University, Faculty of Engineering and Natural Sciences, Istanbul; ( b ) Istanbul BilgiUniversity, Faculty of Engineering and Natural Sciences, Istanbul; ( c ) Department of Physics, BogaziciUniversity, Istanbul; ( d ) Department of Physics Engineering, Gaziantep University, Gaziantep; Turkey. Institute of Physics, Azerbaijan Academy of Sciences, Baku; Azerbaijan. Institut de Física d’Altes Energies (IFAE), Barcelona Institute of Science and Technology, Barcelona;Spain. ( a ) Institute of High Energy Physics, Chinese Academy of Sciences, Beijing; ( b ) Physics Department,Tsinghua University, Beijing; ( c ) Department of Physics, Nanjing University, Nanjing; ( d ) University ofChinese Academy of Science (UCAS), Beijing; China. Institute of Physics, University of Belgrade, Belgrade; Serbia. Department for Physics and Technology, University of Bergen, Bergen; Norway. Physics Division, Lawrence Berkeley National Laboratory and University of California, Berkeley CA;United States of America. Institut für Physik, Humboldt Universität zu Berlin, Berlin; Germany. Albert Einstein Center for Fundamental Physics and Laboratory for High Energy Physics, University ofBern, Bern; Switzerland. School of Physics and Astronomy, University of Birmingham, Birmingham; United Kingdom. Facultad de Ciencias y Centro de Investigaciónes, Universidad Antonio Nariño, Bogota; Colombia. ( a ) INFN Bologna and Universita’ di Bologna, Dipartimento di Fisica; ( b ) INFN Sezione di Bologna; Italy. Physikalisches Institut, Universität Bonn, Bonn; Germany. Department of Physics, Boston University, Boston MA; United States of America. Department of Physics, Brandeis University, Waltham MA; United States of America. ( a ) Transilvania University of Brasov, Brasov; ( b ) Horia Hulubei National Institute of Physics and NuclearEngineering, Bucharest; ( c ) Department of Physics, Alexandru Ioan Cuza University of Iasi, Iasi; ( d ) NationalInstitute for Research and Development of Isotopic and Molecular Technologies, Physics Department,Cluj-Napoca; ( e ) University Politehnica Bucharest, Bucharest; ( f ) West University in Timisoara, Timisoara;Romania. ( a ) Faculty of Mathematics, Physics and Informatics, Comenius University, Bratislava; ( b ) Department ofSubnuclear Physics, Institute of Experimental Physics of the Slovak Academy of Sciences, Kosice; SlovakRepublic. Physics Department, Brookhaven National Laboratory, Upton NY; United States of America. Departamento de Física, Universidad de Buenos Aires, Buenos Aires; Argentina. California State University, CA; United States of America.32 Cavendish Laboratory, University of Cambridge, Cambridge; United Kingdom. ( a ) Department of Physics, University of Cape Town, Cape Town; ( b ) Department of MechanicalEngineering Science, University of Johannesburg, Johannesburg; ( c ) School of Physics, University of theWitwatersrand, Johannesburg; South Africa. Department of Physics, Carleton University, Ottawa ON; Canada. ( a ) Faculté des Sciences Ain Chock, Réseau Universitaire de Physique des Hautes Energies - UniversitéHassan II, Casablanca; ( b ) Faculté des Sciences, Université Ibn-Tofail, Kénitra; ( c ) Faculté des SciencesSemlalia, Université Cadi Ayyad, LPHEA-Marrakech; ( d ) Faculté des Sciences, Université MohamedPremier and LPTPM, Oujda; ( e ) Faculté des sciences, Université Mohammed V, Rabat; Morocco. CERN, Geneva; Switzerland. Enrico Fermi Institute, University of Chicago, Chicago IL; United States of America. LPC, Université Clermont Auvergne, CNRS/IN2P3, Clermont-Ferrand; France. Nevis Laboratory, Columbia University, Irvington NY; United States of America. Niels Bohr Institute, University of Copenhagen, Copenhagen; Denmark. ( a ) Dipartimento di Fisica, Università della Calabria, Rende; ( b ) INFN Gruppo Collegato di Cosenza,Laboratori Nazionali di Frascati; Italy. Physics Department, Southern Methodist University, Dallas TX; United States of America. Physics Department, University of Texas at Dallas, Richardson TX; United States of America. National Centre for Scientific Research "Demokritos", Agia Paraskevi; Greece. ( a ) Department of Physics, Stockholm University; ( b ) Oskar Klein Centre, Stockholm; Sweden. Deutsches Elektronen-Synchrotron DESY, Hamburg and Zeuthen; Germany. Lehrstuhl für Experimentelle Physik IV, Technische Universität Dortmund, Dortmund; Germany. Institut für Kern- und Teilchenphysik, Technische Universität Dresden, Dresden; Germany. Department of Physics, Duke University, Durham NC; United States of America. SUPA - School of Physics and Astronomy, University of Edinburgh, Edinburgh; United Kingdom. INFN e Laboratori Nazionali di Frascati, Frascati; Italy. Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, Freiburg; Germany. II. Physikalisches Institut, Georg-August-Universität Göttingen, Göttingen; Germany. Département de Physique Nucléaire et Corpusculaire, Université de Genève, Genève; Switzerland. ( a ) Dipartimento di Fisica, Università di Genova, Genova; ( b ) INFN Sezione di Genova; Italy. II. Physikalisches Institut, Justus-Liebig-Universität Giessen, Giessen; Germany. SUPA - School of Physics and Astronomy, University of Glasgow, Glasgow; United Kingdom. LPSC, Université Grenoble Alpes, CNRS/IN2P3, Grenoble INP, Grenoble; France. Laboratory for Particle Physics and Cosmology, Harvard University, Cambridge MA; United States ofAmerica. ( a ) Department of Modern Physics and State Key Laboratory of Particle Detection and Electronics,University of Science and Technology of China, Hefei; ( b ) Institute of Frontier and Interdisciplinary Scienceand Key Laboratory of Particle Physics and Particle Irradiation (MOE), Shandong University,Qingdao; ( c ) School of Physics and Astronomy, Shanghai Jiao Tong University, KLPPAC-MoE, SKLPPC,Shanghai; ( d ) Tsung-Dao Lee Institute, Shanghai; China. ( a ) Kirchhoff-Institut für Physik, Ruprecht-Karls-Universität Heidelberg, Heidelberg; ( b ) PhysikalischesInstitut, Ruprecht-Karls-Universität Heidelberg, Heidelberg; Germany. Faculty of Applied Information Science, Hiroshima Institute of Technology, Hiroshima; Japan. ( a ) Department of Physics, Chinese University of Hong Kong, Shatin, N.T., Hong Kong; ( b ) Department ofPhysics, University of Hong Kong, Hong Kong; ( c ) Department of Physics and Institute for Advanced Study,Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong; China. Department of Physics, National Tsing Hua University, Hsinchu; Taiwan.33 Department of Physics, Indiana University, Bloomington IN; United States of America. ( a ) INFN Gruppo Collegato di Udine, Sezione di Trieste, Udine; ( b ) ICTP, Trieste; ( c ) DipartimentoPolitecnico di Ingegneria e Architettura, Università di Udine, Udine; Italy. ( a ) INFN Sezione di Lecce; ( b ) Dipartimento di Matematica e Fisica, Università del Salento, Lecce; Italy. ( a ) INFN Sezione di Milano; ( b ) Dipartimento di Fisica, Università di Milano, Milano; Italy. ( a ) INFN Sezione di Napoli; ( b ) Dipartimento di Fisica, Università di Napoli, Napoli; Italy. ( a ) INFN Sezione di Pavia; ( b ) Dipartimento di Fisica, Università di Pavia, Pavia; Italy. ( a ) INFN Sezione di Pisa; ( b ) Dipartimento di Fisica E. Fermi, Università di Pisa, Pisa; Italy. ( a ) INFN Sezione di Roma; ( b ) Dipartimento di Fisica, Sapienza Università di Roma, Roma; Italy. ( a ) INFN Sezione di Roma Tor Vergata; ( b ) Dipartimento di Fisica, Università di Roma Tor Vergata, Roma;Italy. ( a ) INFN Sezione di Roma Tre; ( b ) Dipartimento di Matematica e Fisica, Università Roma Tre, Roma; Italy. ( a ) INFN-TIFPA; ( b ) Università degli Studi di Trento, Trento; Italy. Institut für Astro- und Teilchenphysik, Leopold-Franzens-Universität, Innsbruck; Austria. University of Iowa, Iowa City IA; United States of America. Department of Physics and Astronomy, Iowa State University, Ames IA; United States of America. Joint Institute for Nuclear Research, Dubna; Russia. ( a ) Departamento de Engenharia Elétrica, Universidade Federal de Juiz de Fora (UFJF), Juiz deFora; ( b ) Universidade Federal do Rio De Janeiro COPPE/EE/IF, Rio de Janeiro; ( c ) Universidade Federal deSão João del Rei (UFSJ), São João del Rei; ( d ) Instituto de Física, Universidade de São Paulo, São Paulo;Brazil. KEK, High Energy Accelerator Research Organization, Tsukuba; Japan. Graduate School of Science, Kobe University, Kobe; Japan. ( a ) AGH University of Science and Technology, Faculty of Physics and Applied Computer Science,Krakow; ( b ) Marian Smoluchowski Institute of Physics, Jagiellonian University, Krakow; Poland. Institute of Nuclear Physics Polish Academy of Sciences, Krakow; Poland. Faculty of Science, Kyoto University, Kyoto; Japan. Kyoto University of Education, Kyoto; Japan. Research Center for Advanced Particle Physics and Department of Physics, Kyushu University, Fukuoka ;Japan. Instituto de Física La Plata, Universidad Nacional de La Plata and CONICET, La Plata; Argentina. Physics Department, Lancaster University, Lancaster; United Kingdom. Oliver Lodge Laboratory, University of Liverpool, Liverpool; United Kingdom. Department of Experimental Particle Physics, Jožef Stefan Institute and Department of Physics,University of Ljubljana, Ljubljana; Slovenia. School of Physics and Astronomy, Queen Mary University of London, London; United Kingdom. Department of Physics, Royal Holloway University of London, Egham; United Kingdom. Department of Physics and Astronomy, University College London, London; United Kingdom. Louisiana Tech University, Ruston LA; United States of America. Fysiska institutionen, Lunds universitet, Lund; Sweden. Centre de Calcul de l’Institut National de Physique Nucléaire et de Physique des Particules (IN2P3),Villeurbanne; France. Departamento de Física Teorica C-15 and CIAFF, Universidad Autónoma de Madrid, Madrid; Spain. Institut für Physik, Universität Mainz, Mainz; Germany.
School of Physics and Astronomy, University of Manchester, Manchester; United Kingdom.
CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille; France.
Department of Physics, University of Massachusetts, Amherst MA; United States of America.34 Department of Physics, McGill University, Montreal QC; Canada.
School of Physics, University of Melbourne, Victoria; Australia.
Department of Physics, University of Michigan, Ann Arbor MI; United States of America.
Department of Physics and Astronomy, Michigan State University, East Lansing MI; United States ofAmerica.
B.I. Stepanov Institute of Physics, National Academy of Sciences of Belarus, Minsk; Belarus.
Research Institute for Nuclear Problems of Byelorussian State University, Minsk; Belarus.
Group of Particle Physics, University of Montreal, Montreal QC; Canada.
P.N. Lebedev Physical Institute of the Russian Academy of Sciences, Moscow; Russia.
National Research Nuclear University MEPhI, Moscow; Russia.
D.V. Skobeltsyn Institute of Nuclear Physics, M.V. Lomonosov Moscow State University, Moscow;Russia.
Fakultät für Physik, Ludwig-Maximilians-Universität München, München; Germany.
Max-Planck-Institut für Physik (Werner-Heisenberg-Institut), München; Germany.
Nagasaki Institute of Applied Science, Nagasaki; Japan.
Graduate School of Science and Kobayashi-Maskawa Institute, Nagoya University, Nagoya; Japan.
Department of Physics and Astronomy, University of New Mexico, Albuquerque NM; United States ofAmerica.
Institute for Mathematics, Astrophysics and Particle Physics, Radboud University Nijmegen/Nikhef,Nijmegen; Netherlands.
Nikhef National Institute for Subatomic Physics and University of Amsterdam, Amsterdam;Netherlands.
Department of Physics, Northern Illinois University, DeKalb IL; United States of America. ( a ) Budker Institute of Nuclear Physics and NSU, SB RAS, Novosibirsk; ( b ) Novosibirsk State UniversityNovosibirsk; Russia.
Institute for Theoretical and Experimental Physics named by A.I. Alikhanov of National ResearchCentre "Kurchatov Institute", Moscow; Russia.
Institute for High Energy Physics of the National Research Centre Kurchatov Institute, Protvino; Russia.
Department of Physics, New York University, New York NY; United States of America.
Ochanomizu University, Otsuka, Bunkyo-ku, Tokyo; Japan.
Ohio State University, Columbus OH; United States of America.
Faculty of Science, Okayama University, Okayama; Japan.
Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, Norman OK; UnitedStates of America.
Department of Physics, Oklahoma State University, Stillwater OK; United States of America.
Palacký University, RCPTM, Joint Laboratory of Optics, Olomouc; Czech Republic.
Center for High Energy Physics, University of Oregon, Eugene OR; United States of America.
LAL, Université Paris-Sud, CNRS/IN2P3, Université Paris-Saclay, Orsay; France.
Graduate School of Science, Osaka University, Osaka; Japan.
Department of Physics, University of Oslo, Oslo; Norway.
Department of Physics, Oxford University, Oxford; United Kingdom.
LPNHE, Sorbonne Université, Université de Paris, CNRS/IN2P3, Paris; France.
Department of Physics, University of Pennsylvania, Philadelphia PA; United States of America.
Konstantinov Nuclear Physics Institute of National Research Centre "Kurchatov Institute", PNPI, St.Petersburg; Russia.
Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh PA; United States ofAmerica. 35 ( a ) Laboratório de Instrumentação e Física Experimental de Partículas - LIP, Lisboa; ( b ) Departamento deFísica, Faculdade de Ciências, Universidade de Lisboa, Lisboa; ( c ) Departamento de Física, Universidade deCoimbra, Coimbra; ( d ) Centro de Física Nuclear da Universidade de Lisboa, Lisboa; ( e ) Departamento deFísica, Universidade do Minho, Braga; ( f ) Universidad de Granada, Granada (Spain); ( g ) Dep Física andCEFITEC of Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Caparica; ( h ) InstitutoSuperior Técnico, Universidade de Lisboa, Lisboa; Portugal.
Institute of Physics of the Czech Academy of Sciences, Prague; Czech Republic.
Czech Technical University in Prague, Prague; Czech Republic.
Charles University, Faculty of Mathematics and Physics, Prague; Czech Republic.
Particle Physics Department, Rutherford Appleton Laboratory, Didcot; United Kingdom.
IRFU, CEA, Université Paris-Saclay, Gif-sur-Yvette; France.
Santa Cruz Institute for Particle Physics, University of California Santa Cruz, Santa Cruz CA; UnitedStates of America. ( a ) Departamento de Física, Pontificia Universidad Católica de Chile, Santiago; ( b ) Universidad AndresBello, Department of Physics, Santiago; ( c ) Departamento de Física, Universidad Técnica Federico SantaMaría, Valparaíso; Chile.
Department of Physics, University of Washington, Seattle WA; United States of America.
Department of Physics and Astronomy, University of Sheffield, Sheffield; United Kingdom.
Department of Physics, Shinshu University, Nagano; Japan.
Department Physik, Universität Siegen, Siegen; Germany.
Department of Physics, Simon Fraser University, Burnaby BC; Canada.
SLAC National Accelerator Laboratory, Stanford CA; United States of America.
Physics Department, Royal Institute of Technology, Stockholm; Sweden.
Departments of Physics and Astronomy, Stony Brook University, Stony Brook NY; United States ofAmerica.
Department of Physics and Astronomy, University of Sussex, Brighton; United Kingdom.
School of Physics, University of Sydney, Sydney; Australia.
Institute of Physics, Academia Sinica, Taipei; Taiwan. ( a ) E. Andronikashvili Institute of Physics, Iv. Javakhishvili Tbilisi State University, Tbilisi; ( b ) HighEnergy Physics Institute, Tbilisi State University, Tbilisi; Georgia.
Department of Physics, Technion, Israel Institute of Technology, Haifa; Israel.
Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Tel Aviv; Israel.
Department of Physics, Aristotle University of Thessaloniki, Thessaloniki; Greece.
International Center for Elementary Particle Physics and Department of Physics, University of Tokyo,Tokyo; Japan.
Graduate School of Science and Technology, Tokyo Metropolitan University, Tokyo; Japan.
Department of Physics, Tokyo Institute of Technology, Tokyo; Japan.
Tomsk State University, Tomsk; Russia.
Department of Physics, University of Toronto, Toronto ON; Canada. ( a ) TRIUMF, Vancouver BC; ( b ) Department of Physics and Astronomy, York University, Toronto ON;Canada.
Division of Physics and Tomonaga Center for the History of the Universe, Faculty of Pure and AppliedSciences, University of Tsukuba, Tsukuba; Japan.
Department of Physics and Astronomy, Tufts University, Medford MA; United States of America.
Department of Physics and Astronomy, University of California Irvine, Irvine CA; United States ofAmerica.
Department of Physics and Astronomy, University of Uppsala, Uppsala; Sweden.36 Department of Physics, University of Illinois, Urbana IL; United States of America.
Instituto de Física Corpuscular (IFIC), Centro Mixto Universidad de Valencia - CSIC, Valencia; Spain.
Department of Physics, University of British Columbia, Vancouver BC; Canada.
Department of Physics and Astronomy, University of Victoria, Victoria BC; Canada.
Fakultät für Physik und Astronomie, Julius-Maximilians-Universität Würzburg, Würzburg; Germany.
Department of Physics, University of Warwick, Coventry; United Kingdom.
Waseda University, Tokyo; Japan.
Department of Particle Physics, Weizmann Institute of Science, Rehovot; Israel.
Department of Physics, University of Wisconsin, Madison WI; United States of America.
Fakultät für Mathematik und Naturwissenschaften, Fachgruppe Physik, Bergische UniversitätWuppertal, Wuppertal; Germany.
Department of Physics, Yale University, New Haven CT; United States of America.
Yerevan Physics Institute, Yerevan; Armenia. a Also at Borough of Manhattan Community College, City University of New York, New York NY; UnitedStates of America. b Also at CERN, Geneva; Switzerland. c Also at CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille; France. d Also at Département de Physique Nucléaire et Corpusculaire, Université de Genève, Genève;Switzerland. e Also at Departament de Fisica de la Universitat Autonoma de Barcelona, Barcelona; Spain. f Also at Departamento de Física, Instituto Superior Técnico, Universidade de Lisboa, Lisboa; Portugal. g Also at Department of Applied Physics and Astronomy, University of Sharjah, Sharjah; United ArabEmirates. h Also at Department of Financial and Management Engineering, University of the Aegean, Chios; Greece. i Also at Department of Physics and Astronomy, Michigan State University, East Lansing MI; UnitedStates of America. j Also at Department of Physics and Astronomy, University of Louisville, Louisville, KY; United States ofAmerica. k Also at Department of Physics, Ben Gurion University of the Negev, Beer Sheva; Israel. l Also at Department of Physics, California State University, East Bay; United States of America. m Also at Department of Physics, California State University, Fresno; United States of America. n Also at Department of Physics, California State University, Sacramento; United States of America. o Also at Department of Physics, King’s College London, London; United Kingdom. p Also at Department of Physics, St. Petersburg State Polytechnical University, St. Petersburg; Russia. q Also at Department of Physics, Stanford University, Stanford CA; United States of America. r Also at Department of Physics, University of Adelaide, Adelaide; Australia. s Also at Department of Physics, University of Fribourg, Fribourg; Switzerland. t Also at Department of Physics, University of Michigan, Ann Arbor MI; United States of America. u Also at Dipartimento di Matematica, Informatica e Fisica, Università di Udine, Udine; Italy. v Also at Faculty of Physics, M.V. Lomonosov Moscow State University, Moscow; Russia. w Also at Giresun University, Faculty of Engineering, Giresun; Turkey. x Also at Graduate School of Science, Osaka University, Osaka; Japan. y Also at Hellenic Open University, Patras; Greece. z Also at Institucio Catalana de Recerca i Estudis Avancats, ICREA, Barcelona; Spain. aa Also at Institut für Experimentalphysik, Universität Hamburg, Hamburg; Germany. ab Also at Institute for Mathematics, Astrophysics and Particle Physics, Radboud UniversityNijmegen/Nikhef, Nijmegen; Netherlands. 37 c Also at Institute for Nuclear Research and Nuclear Energy (INRNE) of the Bulgarian Academy ofSciences, Sofia; Bulgaria. ad Also at Institute for Particle and Nuclear Physics, Wigner Research Centre for Physics, Budapest;Hungary. ae Also at Institute of Particle Physics (IPP), Vancouver; Canada. a f
Also at Institute of Physics, Academia Sinica, Taipei; Taiwan. ag Also at Institute of Physics, Azerbaijan Academy of Sciences, Baku; Azerbaijan. ah Also at Institute of Theoretical Physics, Ilia State University, Tbilisi; Georgia. ai Also at Instituto de Fisica Teorica, IFT-UAM/CSIC, Madrid; Spain. aj Also at Joint Institute for Nuclear Research, Dubna; Russia. ak Also at LAL, Université Paris-Sud, CNRS/IN2P3, Université Paris-Saclay, Orsay; France. al Also at Louisiana Tech University, Ruston LA; United States of America. am Also at LPNHE, Sorbonne Université, Université de Paris, CNRS/IN2P3, Paris; France. an Also at Manhattan College, New York NY; United States of America. ao Also at Moscow Institute of Physics and Technology State University, Dolgoprudny; Russia. ap Also at National Research Nuclear University MEPhI, Moscow; Russia. aq Also at Physics Department, An-Najah National University, Nablus; Palestine. ar Also at Physics Dept, University of South Africa, Pretoria; South Africa. as Also at Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, Freiburg; Germany. at Also at School of Physics, Sun Yat-sen University, Guangzhou; China. au Also at The City College of New York, New York NY; United States of America. av Also at The Collaborative Innovation Center of Quantum Matter (CICQM), Beijing; China. aw Also at Tomsk State University, Tomsk, and Moscow Institute of Physics and Technology StateUniversity, Dolgoprudny; Russia. ax Also at TRIUMF, Vancouver BC; Canada. ay Also at Universita di Napoli Parthenope, Napoli; Italy. ∗∗