Physics Letters B 793 (2019) 469–492 Contents lists available at ScienceDirect Physics Letters B www.elsevier.com/locate/physletb Observation of electroweak W ± Z√boson pair production in association with two jets in pp collisions at s = 13 TeV with the ATLAS detector .The ATLAS Collaboration  a r t i c l e i n f o a b s t r a c t Article history: An observation of electroweak W ± Z production in association with two jets in proton–proton collisions Received 27 December 2018 is presented. The data collected by √the ATLAS detector at the Large Hadron Collider in 2015 and Received in revised form 16 April 2019 2016 at a centre-of-mass energy of s = 13 TeV are used, corresponding to an integrated luminosity Accepted 6 May 2019 of 36.1 fb−1 . Events containing three identified leptons, either electrons or muons, and two jets are Available online 13 May 2019 selected. The electroweak production of W ± Z bosons in association with two jets is measured with Editor: M. Doser an observed significance of 5.3 standard deviations. A fiducial cross-section for electroweak production including interference effects and for a single leptonic decay mode is measured to be σ W Z j j −EW = 0.57 + 0.14 +0.07 ± −0.13 (stat.) −0.06 (syst.) fb. Total and differential fiducial cross-sections of the sum of W Z j j electroweak and strong productions for several kinematic observables are also measured. © 2019 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). Funded by SCOAP3 . 1. Introduction Different searches for diboson electroweak production have been performed by the ATLAS and CMS collaborations at the LHC. So far, electroweak V V j j production has only been observed in The scattering of vector bosons (VBS), V V → V V with V = the same-sign W ± W ± j j √channel by CMS using data collected at a W / Z /γ , is a key process with which to probe the SU(2)L × U(1)Y centre-of-mass energy of s = 13 TeV [6]. Evidence of electroweak gauge symmetry of the electroweak (EW) theory that determines V V j j production has also been obtained in the W ± W ± j j [7,8] the self-couplings of the vector bosons. New phenomena be- and Z γ j j [9] channels by ATLAS and √ CMS, respectively, using yond the Standard Model (SM) can alter the couplings of vector smaller samples of data recorded at s = 8 TeV. Limits on elec- bosons, generating additional contributions to quartic gauge cou- troweak cross-sections for the production of two gauge boson have plings (QGC) compared with the SM predictions [1–3]. been reported for the W ± Z j j [10,11], Z Z j j [12], Z γ j j [13] and In proton–proton collisions, VBS is initiated by an interaction of W γ j j [14] channels by ATLAS and CMS. two vector bosons radiated from the initial-state quarks, yielding a This Letter reports on an observation and measurement of final state with two bosons and two jets, V V j j, in a purely elec- electroweak W ± Z j j production, exploiting the fully leptonic final troweak process [4]. VBS diagrams are not independently gauge states where both the Z and W bosons decay into electrons or invariant and cannot be studied separately from other processes muons. The pp collision data were collected with the ATLAS detec- √ leading to the same V V j j final state [5]. Two categories of pro- tor in 2015 and 2016 at a centre-of-mass energy of s = 13 TeV cesses give rise to V V j j final states. The first category, which in- and correspond to an integrated luminosity of 36.1 fb−1 . cludes VBS contributions, involves exclusively weak interactions at 6 Born level of order αEW including the boson decays, where αEW is 2. The ATLAS detector the electroweak coupling constant. It is referred to as electroweak production. The second category involves both the strong and elec- The ATLAS detector [15] is a multipurpose detector with a troweak interactions at Born level of order αS2 αEW 4 , where αS is the cylindrical geometry1 and nearly 4π coverage in solid angle. The strong interaction coupling constant. It is referred to as QCD pro- collision point is surrounded by inner tracking detectors, collec- duction. According to the SM a small interference occurs between electroweak and QCD production. 1 ATLAS uses a right-handed coordinate system with its origin at the nominal interaction point (IP) in the centre of the detector and the z-axis along the beam direction. The x-axis points from the IP to the centre of the LHC ring, and the y-axis  E-mail address: atlas.publications@cern.ch. points upward. Cylindrical coordinates (r , φ) are used in the transverse (x, y ) plane, https://doi.org/10.1016/j.physletb.2019.05.012 0370-2693/© 2019 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). Funded by SCOAP3 . 470 The ATLAS Collaboration / Physics Letters B 793 (2019) 469–492 tively referred to as the inner detector (ID), located within a super- gle between the lepton and the neutrino in the transverse plane conducting solenoid providing a 2 T axial magnetic field, followed and p νT is the transverse momentum of the neutrino, is required by a calorimeter system and a muon spectrometer (MS). to be mTW > 30 GeV. The angular distance between the charged The inner detector provides precise measurements of charged- lepton from the W ± decay and each of the charged leptons from particle tracks in the pseudorapidity range |η| < 2.5. It consists the Z decay is required to be R > 0.3, and the angular dis- of three subdetectors arranged in a coaxial geometry around the tance between the two leptons from the Z decay is required to be beam axis: a silicon pixel detector, a silicon microstrip detector R > 0.2. Requiring that the transverse momentum of the lead- and a transition radiation tracker. ing lepton be above 27 GeV reduces the acceptance of the fiducial The electromagnetic calorimeter covers the region |η| < 3.2 and phase space by only 0.02% and is therefore not added to the def- is based on high-granularity, lead/liquid-argon (LAr) sampling tech- inition of the fiducial phase space, although it is present in the nology. The hadronic calorimeter uses a steel/scintillator-tile de- selection at the detector level presented in Section 5. tector in the region |η| < 1.7 and a copper/LAr detector in the In addition to these requirements that define an inclusive phase region 1.5 < |η| < 3.2. The most forward region of the detector, space, at least two jets with p T > 40 GeV and |η j | < 4.5 are re- 3.1 < |η| < 4.9, is equipped with a forward calorimeter, measuring quired. These particle-level jets are reconstructed from stable par- electromagnetic and hadronic energies in copper/LAr and tung- ticles with a lifetime of τ > 30 ps in the simulation after parton sten/LAr modules. showering, hadronisation, and decay of particles with τ < 30 ps. The muon spectrometer comprises separate trigger and high- Muons, electrons, neutrinos and photons associated with W and precision tracking chambers to measure the deflection of muons Z decays are excluded. The particle-level jets are reconstructed in a magnetic field generated by three large superconducting using the anti-kt [10] algorithm with a radius parameter R = toroidal magnets arranged with an eightfold azimuthal coil sym- 0.4. The angular distance between all selected leptons and jets metry around the calorimeters. The high-precision chambers cover is required to be R ( j , ) > 0.3. If the R ( j , ) requirement is the range |η| < 2.7 with three layers of monitored drift tubes, not satisfied, the jet is discarded. The invariant mass, m j j , of the complemented by cathode strip chambers in the forward region, two highest-p T jets in opposite hemispheres, η j1 · η j2 < 0, is re- where the particle flux is highest. The muon trigger system covers quired to be m j j > 500 GeV to enhance the sensitivity to VBS the range |η| < 2.4 with resistive-plate chambers in the barrel and processes. These two jets are referred to as tagging jets. Finally, thin-gap chambers in the endcap regions. processes with a b-quark in the initial state, such as t Z j produc- A two-level trigger system is used to select events in real tion, are not considered as signal. The production of t Z j results time [16]. It consists of a hardware-based first-level trigger and from a t-channel exchange of a W boson between a b- and a a software-based high-level trigger. The latter employs algorithms u-quark giving a final state with a t-quark, a Z boson and a light- similar to those used offline to identify electrons, muons, photons quark jet, but does not include diagrams with gauge boson cou- and jets. plings. 3. Phase space for cross-section measurements 4. Signal and background simulation The W ± Z j j electroweak cross-section is measured in a fidu- Monte Carlo simulation is used to model signal and background cial phase space that is defined by the kinematics of the final-state processes. All generated MC events were passed through the ATLAS leptons, electrons or muons, associated with the W ± and Z boson detector simulation [20], based on Geant 4 [21], and processed decays, and of two jets. Leptons produced in the decay of a hadron, using the same reconstruction software as used for the data. The a τ -lepton, or their descendants are not considered in the defini- event samples include the simulation of additional proton–proton tion of the fiducial phase space. At particle level, the kinematics interactions (pile-up) generated with Pythia 8.186 [22] using the of the charged lepton after quantum electrodynamics (QED) final- MSTW2008LO [23] parton distribution functions (PDF) and the state radiation (FSR) are ‘dressed’ by including  contributions from A2 [24] set of tuned parameters. photons with an angular distance R ≡ ( η)2 + ( φ)2 < 0.1 Scale factors are applied to simulated events to correct for the from the lepton. Dressed charged leptons, and final-state neutrinos differences between data and MC simulation in the trigger, recon- that do not originate from hadron or τ -lepton decays, are matched struction, identification, isolation and impact parameter efficiencies to the W ± and Z boson decay products using a Monte Carlo (MC) of electrons and muons [25,26]. Furthermore, the electron energy generator-independent algorithmic approach, called the ‘resonant and muon momentum in simulated events are smeared to account shape’ algorithm. This algorithm is based on the value of an esti- for differences in resolution between data and MC simulation [26, mator expressing the product of the nominal line shapes of the W 27]. and Z resonances as detailed in Ref. [10]. The Sherpa 2.2.2 MC event generator [28–35] was used to The fiducial phase space of the measurement matches the one model W ± Z j j events. It includes the modelling of hard scatter- used in Refs. [10,17] and is defined at particle level by the fol- ing, parton showering, hadronisation and the underlying event. A lowing requirements: the charged leptons from the Z boson de- MC event sample, referred to as W Z j j −EW, includes processes of cay are required to have transverse momentum p T > 15 GeV, the order six (zero) in αEW (αS ). In this sample, which includes VBS charged lepton from the W ± decay is required to have trans- diagrams, two additional jets originating from electroweak ver- verse momentum p T > 20 GeV, the charged leptons from the W ± tices from matrix-element partons are included in the final state. and Z bosons are required to have |η| < 2.5 and the invariant Diagrams with a b-quark in either the initial or final state, i.e. mass of the two leptons from the Z boson decay must be within b-quarks in the matrix-element calculation, are not considered. 10 GeV of the nominal Z boson mass, taken from the world av- This sample provides a LO prediction for the W Z j j −EW signal erage value, mPDG [18]. The W boson transverse mass, defined as  Z process. A second MC event sample, referred to as W Z j j −QCD, mTW = 2 · p νT · p T · [1 − cos φ( , ν )], where φ( , ν ) is the an- includes processes of order four in αEW in the matrix-element of W ± Z production with up to one jet calculated at next-to- leading order (NLO) and with a second or third jet calculated φ being the azimuthal angle around the beam direction. The pseudorapidity is de- at leading order (LO). This W Z j j −QCD sample includes matrix- fined in terms of the polar angle θ as η = −ln[tan(θ/2)]. element b-quarks. Both Sherpa samples were generated using the The ATLAS Collaboration / Physics Letters B 793 (2019) 469–492 471 NNPDF3.0 [36] PDF set. Interferences between the two processes verse momentum of the muon must satisfy p T > 15 GeV and its were estimated at LO using the MadGraph5_aMC@NLO 2.3 [37] pseudorapidity must satisfy |η| < 2.5. MC event generator with the NNPDF3.0 PDF set, including only Electron candidates are reconstructed from energy clusters in contributions to the squared matrix-element of order one in the electromagnetic calorimeter matched to ID tracks. Electrons are αS . They are found to be positive and approximately 10% of identified using a likelihood function constructed from information the W Z j j −EW cross-section in the fiducial phase space and are from the shape of the electromagnetic showers in the calorime- treated as an uncertainty in the measurement, as discussed in Sec- ter, track properties and track-to-cluster matching quantities [25]. tion 8. For the estimation of modelling uncertainties, alternative Electrons must satisfy a ‘medium’ likelihood requirement, which MC samples of W Z j j −QCD and W Z j j −EW processes were gener- provides an overall identification efficiency of 90%. The electron ated with MadGraph5_aMC@NLO 2.3 at LO in QCD, including up momentum is computed from the cluster energy and the direction to two partons in the matrix-element for W Z j j −QCD, and using of the track. The transverse momentum of the electron must sat- the NNPDF3.0 PDF set. MC samples of inclusive W ± Z produc- isfy p T > 15 GeV and the pseudorapidity of the cluster must be in tion generated at NLO in QCD with the Powheg-Box v2 [38–41] the ranges |η| < 1.37 or 1.52 < |η| < 2.47. generator, interfaced to Pythia 8.210 or Herwig++ 2.7.1 [42] for Electron and muon candidates are required to originate from simulation of parton showering and hadronisation are also used the primary vertex. The significance of the track’s transverse im- for tests of the modelling of W Z j j −QCD events. pact parameter relative to the beam line must satisfy |d0 /σd0 | < The qq̄ → Z Z (∗) processes were generated with Sherpa 2.2.2 3 (5) for muons (electrons), and the longitudinal impact parame- and the NNPDF3.0 PDF set. Similarly to W ± Z simulation, the ter, z0 (the difference between the value of z of the point on the Z Z j j −QCD and Z Z j j −EW processes are generated separately with track at which d0 is defined and the longitudinal position of the the same matrix-element accuracy as for the W ± Z Sherpa MC primary vertex), is required to satisfy | z0 · sin(θ)| < 0.5 mm. samples. The Sherpa 2.1.1 MC event generator was used to model Electrons and muons are required to be isolated from other the g g → Z Z (∗) and V V V processes at LO using the CT10 [43] particles, according to calorimeter-cluster and ID-track informa- PDF set. The t t̄ V processes were generated at NLO with the Mad- tion. The isolation requirement for electrons varies with p T and Graph5_aMC@NLO 2.3 MC generator using the NNPDF3.0 PDF set is tuned for an efficiency of at least 90% for p T > 25 GeV and at interfaced to the Pythia 8.186 parton shower model. The associ- least 99% for p T > 60 GeV [25]. Fixed thresholds values are used ated production of a single top quark and a Z boson was simulated for the muon isolation variables, providing an efficiency above 90% at LO with MadGraph5_aMC@NLO 2.3 using the NNPDF3.0 PDF for p T > 15 GeV and at least 99% for p T > 60 GeV [26]. set and interfaced to Pythia 8.186 for parton shower. Jets are reconstructed from clusters of energy depositions in the calorimeter [44] using the anti-kt algorithm [19] with a ra- 5. Event selection dius parameter R = 0.4. Events with jets arising from detector noise or other non-collision sources are discarded [45]. All jets Candidate events were selected using single-leptons triggers [16] must have p T > 25 GeV and be reconstructed in the pseudora- that required at least one electron or muon. The transverse mo- pidity range |η| < 4.5. A multivariate combination of track-based mentum threshold of the leptons in 2015 was 24 GeV for electrons variables is used to suppress jets originating from pile-up in the and 20 GeV for muons satisfying a loose isolation requirement ID acceptance [46]. The energy of jets is calibrated using a jet en- based only on ID track information. Due to the higher instan- ergy correction derived from simulation and in situ methods using taneous luminosity in 2016 the trigger threshold was increased data [47]. Jets in the ID acceptance with p T > 25 GeV contain- to 26 GeV for both the electrons and muons and tighter iso- ing a b-hadron are identified using a multivariate algorithm [48, lation requirements were applied. Possible inefficiencies for lep- 49] that uses impact parameter and reconstructed secondary ver- tons with large transverse momenta were reduced by including tex information of the tracks contained in the jets. Jets initiated by additional electron and muon triggers that did not include any isolation requirements with transverse momentum thresholds of b-quarks are selected by setting the algorithm’s output threshold p T = 60 GeV and 50 GeV, respectively. Finally, a single-electron such that a 70% b-jet selection efficiency is achieved in simulated trigger requiring p T > 120 GeV or p T > 140 GeV in 2015 and 2016, t t̄ events. respectively, with less restrictive electron identification criteria was The transverse momentum of the neutrino is estimated from used to increase the selection efficiency for high-p T electrons. the missing transverse momentum in the event, E Tmiss , calculated The combined efficiency of these triggers is close to 100% for as the negative vector sum of the transverse momentum of all W ± Z j j events. Only data recorded with stable beam conditions identified hard (high p T ) physics objects (electrons, muons and and with all relevant detector subsystems operational are consid- jets), as well as an additional soft term. A track-based measure- ered. ment of the soft term [50,51], which accounts for low-p T tracks Events are required to have a primary vertex reconstructed not assigned to a hard object, is used. from at least two charged-particle tracks and compatible with the Events are required to contain exactly three lepton candidates pp interaction region. If several such vertices are present in the satisfying the selection criteria described above. To ensure that the event, the one with the highest sum of the p 2T of the associated trigger efficiency is well determined, at least one of the candidate tracks is selected as the production vertex of the W ± Z . All final leptons is required to have p T > 25 GeV or p T > 27 GeV for the states with three charged leptons (electrons or muons) and neutri- 2015 or 2016 data, respectively, and to be geometrically matched nos from W ± Z leptonic decays are considered. to a lepton that was selected by the trigger. Muon candidates are identified by tracks reconstructed in the To suppress background processes with at least four prompt muon spectrometer and matched to tracks reconstructed in the leptons, events with a fourth lepton candidate satisfying looser inner detector. Muons are required to satisfy a ‘medium’ identi- selection criteria are rejected. For this looser selection, the p T re- fication selection that is based on requirements on the number quirement for the leptons is lowered to p T > 5 GeV and ‘loose’ of hits in the ID and the MS [26]. The efficiency of this selection identification requirements are used for both the electrons and averaged over p T and η is > 98%. The muon momentum is calcu- muons. A less stringent requirement is applied for electron isola- lated by combining the MS measurement, corrected for the energy tion based only on ID track information and electrons with cluster deposited in the calorimeters, with the ID measurement. The trans- in the range 1.37 ≤ |η| ≤ 1.52 are also considered. 472 The ATLAS Collaboration / Physics Letters B 793 (2019) 469–492 Table 1 Expected and observed numbers of events in the W ± Z j j signal region and in the three control regions, before the fit. The expected number of W Z j j −EW events from Sherpa and the estimated number of background events from the other processes are shown. The sum of the backgrounds containing misidentified leptons is labelled ‘Misid. leptons’. The contribution arising from interferences between W Z j j −QCD and W Z j j −EW processes is not included in the table. The total uncertainties are quoted. SR W Z j j −QCD CR b-CR Z Z -CR Data 161 213 141 52 Total predicted 200 ± 41 290 ± 61 160 ± 14 45.2 ± 7.5 W Z j j −EW (signal) 24.9 ± 1.4 8.45 ± 0.37 1.36 ± 0.10 0.21 ± 0.12 W Z j j −QCD 144 ± 41 231 ± 60 24.4 ± 1.7 1.43 ± 0.22 Misid. leptons 9.8 ± 3.9 17.7 ± 7.1 30 ± 12 0.47 ± 0.21 Z Z j j −QCD 8.1 ± 2.2 15.0 ± 3.9 1.96 ± 0.49 35 ± 11 tZj 6.5 ± 1.2 6.6 ± 1.1 36.2 ± 5.7 0.18 ± 0.04 t t̄ + V 4.21 ± 0.76 9.11 ± 1.40 65.4 ± 10.3 2.8 ± 0.61 Z Z j j −EW 1.80 ± 0.45 0.53 ± 0.14 0.12 ± 0.09 4.1 ± 1.4 VVV 0.59 ± 0.15 0.93 ± 0.23 0.13 ± 0.03 1.05 ± 0.30 Candidate events are required to have at least one pair of lep- to as W Z j j −QCD CR, is defined by selecting a sub-sample of tons of the same flavour and of opposite charge, with an invariant W ± Z j j candidate events with m j j < 500 GeV and no reconstructed mass that is consistent with the nominal Z boson mass [52] to b-jets. within 10 GeV. This pair is considered to be the Z boson candi- The other main sources of irreducible background arise from date. If more than one pair can be formed, the pair whose invariant Z Z and t t̄ + V (where V = Z or W ). These irreducible backgrounds mass is closest to the nominal Z boson mass is taken as the Z bo- are also modelled using MC simulations. Data in two additional son candidate. dedicated control regions, referred to as Z Z -CR and b-CR, respec- The remaining third lepton is assigned to the W boson decay. tively, are used to constrain the normalisations of the Z Z j j −QCD The transverse mass of the W candidate, computed using E Tmiss and t t̄ + V backgrounds. The control region Z Z -CR, enriched in Z Z and the p T of the associated lepton, is required to be greater than events, is defined by applying the W ± Z j j event selection defined 30 GeV. in Section 5, with the exception that instead of vetoing a fourth Backgrounds originating from misidentified leptons are sup- lepton it is required that events have at least a fourth lepton can- pressed by requiring the lepton associated with the W boson to didate with looser identification requirements. This region is domi- satisfy more stringent selection criteria. Thus, the transverse mo- nated by Z Z j j −QCD events with a small contribution of Z Z j j −EW mentum of these leptons is required to be p T > 20 GeV. Further- events. The control region b-CR, enriched in t t̄ + V events, is de- more, leptons associated with the W boson decay are required to fined by selecting W ± Z j j candidate events having at least one satisfy the ‘tight’ identification requirements, which have an ef- reconstructed b-jet. Remaining sources of irreducible background ficiency between 90% and 98% for muons and an efficiency of are Z Z j j −EW V V V and t Z j events. Their contributions in the 85% for electrons. Finally, muons must also satisfy a tighter iso- control and signal regions are estimated from MC simulations. lation requirement, tuned for an efficiency of at least 90% (99%) The reducible backgrounds originate from Z + j, Z γ , t t̄, W t for p T > 25 (60) GeV. and W W production processes. The reducible backgrounds are es- To select W ± Z j j candidates, events are further required to be timated using a data-driven method based on the inversion of a associated with at least two ‘tagging’ jets. The leading tagging jet global matrix containing the efficiencies and the misidentification is selected as the highest-p T jet in the event with p T > 40 GeV. probabilities for prompt and fake leptons [10,53]. The method ex- The second tagging jet is selected as the one with the highest p T among the remaining jets that have a pseudorapidity of opposite ploits the classification of the lepton as loose or tight candidates sign to the first tagging jet and a p T > 40 GeV. These two jets and the probability that a fake lepton is misidentified as a loose are required to verify m j j > 150 GeV, in order to minimise the or tight lepton candidate. Tight leptons candidates are signal lep- contamination from triboson processes. ton candidates as defined in Section 5. Loose lepton candidates The final signal region (SR) for VBS processes is defined by re- are leptons that do not meet the isolation and identification crite- quiring that the invariant mass of the two tagging jets, m j j , be ria of signal lepton candidates but satisfy only looser criteria. The above 500 GeV and that no b-tagged jet be present in the event. misidentification probabilities for fake leptons are determined from data, using dedicated control samples enriched in non-prompt lep- 6. Background estimation tons from heavy-flavour jets and in misidentified leptons from photon conversions or charged hadrons in light-flavour jets. The The background sources are classified into two groups: events lepton misidentification probabilities are applied to samples of where at least one of the candidate leptons is not a prompt lep- W ± Z j j candidate events in data where at least one and up to ton (reducible background) and events where all candidates are three of the lepton candidates are loose. Then, using a matrix prompt leptons or are produced in the decay of a τ -lepton (irre- inversion, the number of events with at least one misidentified ducible background). Candidates that are not prompt leptons are lepton, which represents the amount of reducible background in also called ‘misidentified’ or ‘fake’ leptons. the selected W ± Z j j sample, is obtained. The dominant source of background originates from the QCD- The number of observed events together with the expected induced production of W ± Z dibosons in association with two jets, background contributions are summarised in Table 1 for the signal W Z j j −QCD. The shapes of distributions of kinematic observables region and the three control regions. All sources of uncertainties, of this irreducible background are modelled by the Sherpa MC as described in Section 8, are included. The expected signal purity simulation. The normalisation of this background is, however, con- in the W ± Z j j signal region is about 13%, and 72% of the events strained by data in a dedicated control region. This region, referred arise from W Z j j −QCD production. The ATLAS Collaboration / Physics Letters B 793 (2019) 469–492 473 7. Signal extraction procedure Given the small contribution to the signal region of W Z j j −EW processes, a multivariate discriminant is used to separate the signal from the backgrounds. A boosted decision tree (BDT), as imple- mented in the TMVA package [54], is used to exploit the kinematic differences between the W Z j j −EW signal and the W Z j j −QCD and other backgrounds. The BDT is trained and optimised on sim- ulated events to separate W Z j j −EW events from all background processes. A total of 15 variables are combined into one discriminant, the BDT score output value in the range [−1, 1]. The variables can be classified into three categories: jet-kinematic variables, vector- bosons-kinematics variables, and variables related to both jets and leptons kinematics. The variables related to the kinematic prop- erties of the two tagging jets are the invariant mass of the two jets, m j j , the transverse momenta of the jets, the difference in pseudorapidity and azimuthal angle between the two jets, η j j and φ j j , the rapidity of the leading jet and the jet multiplic- ity. Variables related to the kinematic properties of the vector bosons are the transverse momenta of the W and Z bosons, Fig. 1. Post-fit distribution of the BDT score distribution in the W Z j j −QCD control region. Signal and backgrounds are normalised to the expected number of events af- the pseudorapidity of the W boson, the absolute difference be- ter the fit. The uncertainty band around the MC expectation includes all systematic tween the rapidities of the Z boson and the lepton from the uncertainties as obtained from the fit. decay of the W boson, | y Z − y , W |, and the transverse mass of the W ± Z system mTW Z . The pseudorapidity of the W boson sented in Section 6 and is allowed to vary within its uncer- is reconstructed using an estimate of the longitudinal momen- tainty. tum of the neutrino obtained using the W mass constraint as The determination of the fiducial cross-section is carried out detailed in Ref. [55]. The mTW Z observable is reconstructed fol- using the signal strength parameter μ W Z j j −EW : lowing Ref. [10]. Variables that relate the kinematic properties of signal fid. jets and leptons are the distance in the pseudorapidity–azimuth N data σW Z j j −EW plane between the Z boson and the leading jet, R ( j 1 , Z ), the μW Z j j−EW = signal = fid.,MC , event balance R hard N MC σW Z j j −EW p T , defined as the transverse component of the vector sum of the W Z bosons and tagging jets momenta, nor- signal malised to their scalar p T sum, and, finally the centrality of where N data is the signal yield extracted from data by the signal the W Z system relative to the tagging jets, defined as ζlep. = fit and N MC is the number of signal events predicted by the fid. min( η− , η+ ), with η− = min(η W , η Z , η Z1 ) − min(η j1 , η j2 ) 2 Sherpa MC simulation. The measured cross-section σ W Z j j −EW is and η+ = max(η j 1 , η j 2 ) − max(η W , η Z , η Z1 ). A larger set of dis- derived from the signal strength μ W Z j j −EW by multiplying it by 2 fid., MC criminating observables was studied but only variables improving the Sherpa MC cross-section prediction σ W Z j j −EW in the fiducial signal-to-background were retained. The good modelling by MC region. The W Z j j −QCD contribution that is considered as back- simulations of the distribution shapes and the correlations of all ground in the fit procedure does not contain interference between input variables to the BDT is verified in the W Z j j −QCD CR, as ex- the W Z j j −QCD and W Z j j −EW processes. The measured cross- emplified by the good description of the BDT score distribution of fid. section σ W Z j j −EW therefore formally corresponds to the cross- data in the W Z j j −QCD CR shown in Fig. 1. section of the electroweak production including interference ef- The distribution of the BDT score in the W ± Z j j signal region fects. is used to extract the significance of the W Z j j −EW signal and to measure its fiducial cross-section via a maximum-likelihood fit. 8. Systematic uncertainties An extended likelihood is built from the product of four likeli- hoods corresponding to the BDT score distribution in the W ± Z j j Systematic uncertainties in the signal and control regions af- SR, the m j j distribution in the W Z j j −QCD CR, the multiplicity of fecting the shape and normalisation of the BDT score, m j j and reconstructed b-quarks in the b-CR and the m j j distribution in the N b−jets distributions for the individual backgrounds, as well as the Z Z -CR. The inclusion of the three control regions in the fit allows acceptance of the signal and the shape of its template are consid- the yields of the W Z j j −QCD, t t̄ + V and Z Z j j −QCD backgrounds ered. If the variation of a systematic uncertainty as a function of to be constrained by data. The shapes of these backgrounds are the BDT score is consistent with being due to statistical fluctua- taken from MC predictions and can vary within the uncertain- tions, this systematic uncertainty is neglected. ties affecting the measurement as described in Section 8. The Systematic uncertainties due to the theoretical modelling in the normalisations of these backgrounds are introduced in the like- event generator used to evaluate the W Z j j −QCD and W Z j j −EW lihood as parameters, labelled μ W Z j j −QCD , μtt̄ + V and μ Z Z j j −QCD templates are considered. Uncertainties due to higher order QCD for W Z j j −QCD, t t̄ + V and Z Z j j −QCD backgrounds, respectively. corrections are evaluated by varying the renormalisation and fac- They are treated as unconstrained nuisance parameters that are torisation scales independently by factors of two and one-half, determined mainly by the data in the respective control region. removing combinations where the variations differ by a factor of The normalisation and shape of the other irreducible backgrounds four. These uncertainties are of −20% to +30% on the W Z j j −QCD are taken from MC simulations and are allowed to vary within background normalisation and up to ±5% on the W Z j j −EW sig- their respective uncertainties. The distribution of the reducible nal shape. The uncertainties due to the PDF and the αS value background is estimated from data using the matrix method pre- used in the PDF determination are evaluated using the PDF4LHC 474 The ATLAS Collaboration / Physics Letters B 793 (2019) 469–492 prescription [56]. They are of the order of 1% to 2% in shape Table 2 of the predicted cross-section. A global modelling uncertainty Summary of the relative uncertainties in the measured fiducial fid. cross-section σ W . The uncertainties are reported as per- in the W Z j j −QCD background template that includes effects Z j j −EW centages. of the parton shower model is estimated by comparing predic- tions of the BDT score distribution in the signal region from the Source Uncertainty [%] Sherpa and MadGraph MC event generators. The difference be- W Z j j −EW theory modelling 4.8 tween the predicted shapes of the BDT score distribution from W Z j j −QCD theory modelling 5.2 W Z j j −EW and W Z j j −QCD interference 1.9 the two generators is considered as an uncertainty. The resulting uncertainty ranges from 5% to 20% at medium and high values Jets 6.6 Pile-up 2.2 of the BDT score, respectively. Alternatively, using two MC sam- Electrons 1.4 ples with different parton shower models, Powheg+Pythia8 and Muons 0.4 Powheg+Herwig, it was verified that for W Z j j −QCD events the b-tagging 0.1 variations of the BDT score shape due to different parton shower MC statistics 1.9 Misid. lepton background 0.9 models are within the global modelling uncertainty defined above. Other backgrounds 0.8 A global modelling uncertainty in the W Z j j −EW signal template Luminosity 2.1 is also estimated by comparing predictions of the BDT score dis- tribution in the signal region from the Sherpa and MadGraph MC Total Systematics 10.9 event generators. This modelling uncertainty affects the shape of the BDT score distribution by at most 14% at large values of the background sources other than W Z j j −QCD is evaluated by propa- BDT score. The Sherpa W Z j j −EW sample used in this analysis was gating the uncertainty in their MC cross-sections. These are 20% recently found to implement a colour flow computation in VBS-like for V V V [59], 15% for t Z j [10] and t t̄ + V [60], and 25% for processes that increases central parton emissions from the par- Z Z j j −QCD to account for the potentially large impact of scale vari- ton shower [57]. It was verified that possible effects on kinematic ations. distributions and especially on the BDT score distribution are cov- The uncertainty in the combined 2015+2016 integrated lumi- ered by the modelling uncertainty used. The interference between nosity is 2.1%. It is derived, following a methodology similar to electroweak- and QCD-induced processes is not included in the that detailed in Ref. [61], and using the LUCID-2 detector for the probability distribution functions of the fit but is considered as an baseline luminosity measurements [62], from a calibration of the uncertainty affecting only the shape of the W Z j j −EW MC tem- luminosity scale using x– y beam-separation scans. plate. The effect is determined using the MadGraph MC generator, The effect of the systematic uncertainties on the final results resulting for the signal region in shape-only uncertainties ranging after the maximum-likelihood fit is shown in Table 2 where the from 10% to 5% at low and high values of the BDT score, respec- breakdown of the contributions to the uncertainties in the mea- tively. The effect of interference on the shape of the W Z j j −EW sured fiducial cross-section σ W fid. is presented. The individual Z j j −EW MC template in the W ± Z j j-QCD CR is negligible and is therefore sources of systematic uncertainty are combined into theory mod- not included. elling and experimental categories. As shown in the table, the sys- Systematic uncertainties affecting the reconstruction and en- tematic uncertainties in the jet reconstruction and calibration play ergy calibration of jets, electrons and muons are propagated a dominant role, followed by the uncertainties in the modelling through the analysis. The dominant sources of uncertainties are of the W Z j j −EW signal and of the W Z j j −QCD background. Sys- the jet energy scale calibration, including the modelling of pile- tematic uncertainties in the missing transverse momentum com- up. √ The uncertainties in the jet energy scale are obtained from putation arise directly from the momentum and energy calibration s = 13 TeV simulations and in situ measurements [47]. The un- of jets, electrons and muons and are included in the respective certainty in the jet energy resolution [58] and in the suppression lines of Table 2. Systematic uncertainties in the modelling of the of jets originating from pile-up are also considered [46]. The un- reducible and irreducible backgrounds other than W Z j j −QCD are certainties in the b-tagging efficiency and the mistag rate are also also detailed. taken into account. The effect of jet uncertainties on the expected number of events ranges from 10% to 3% at low and high values 9. Cross-section measurements of the BDT score, respectively, with a similar effect for W Z j j −QCD and W Z j j −EW events. The signal strength μ W Z j j −EW and its uncertainty are deter- The uncertainty in the E Tmiss measurement is estimated by prop- mined with a profile-likelihood-ratio test statistic [63]. Systematic agating the uncertainties in the transverse momenta of hard uncertainties in the input templates are treated as nuisance pa- physics objects and by applying momentum scale and resolution rameters with an assumed Gaussian distribution. The distributions uncertainties to the track-based soft term [50,51]. The uncertainties due to lepton reconstruction, identification, of m j j in the Z Z -CR control region, of N b−jets in the b-CR, of m j j isolation requirements and trigger efficiencies are estimated using in the W Z j j −QCD control region and of the BDT score in the tag-and-probe methods in Z → events [25,26]. Uncertainties in signal region, with background normalisations, signal normalisa- the lepton momentum scale and resolution are also assessed using tion and nuisance parameters adjusted by the profile-likelihood fit Z → events [26,27]. These uncertainties impact the expected are shown in Fig. 2. The corresponding post-fit yields are detailed number of events by 1.4% and 0.4% for electrons and muons, re- in Table 3. The table presents the integral of the BDT score dis- spectively, and are independent of the BDT score. Their effect is tribution in the SR, but the uncertainty on the measured signal similar for W Z j j −QCD and W Z j j −EW events. cross section is dominated by events at high BDT score. The signal A 40% yield uncertainty is assigned to the reducible background strength is measured to be estimate. This takes into account the limited number of events in the control regions as well as the differences in background com- μW Z j j−EW = 1.77 + 0.44 +0.15 −0.40 (stat.) −0.12 (exp. syst.) position between the control regions used to determine the lepton +0.15 +0.15 +0.04 misidentification rate and the control regions used to estimate −0.12 (mod. syst.) −0.13 (theory) −0.02 (lumi.) the yield in the signal region. The uncertainty due to irreducible = 1.77 + 0.51 −0.45 , The ATLAS Collaboration / Physics Letters B 793 (2019) 469–492 475 Fig. 2. Post-fit distributions of (a) m j j in the Z Z -CR control region, (b) N b−jets in the b-CR, (c) m j j in the W Z j j −QCD control region and (d) the BDT score distribution in the signal region. Signal and backgrounds are normalised to the expected number of events after the fit. The uncertainty band around the MC expectation includes all systematic uncertainties as obtained from the fit. Table 3 Observed and expected numbers of events in the W ± Z j j signal region and in the three control regions, after the fit. The expected number of W Z j j −EW events from Sherpa and the estimated number of background events from the other processes are shown. The sum of the backgrounds containing misidentified leptons is labelled ‘Misid. leptons’. The total correlated post-fit uncertainties are quoted. SR W Z j j −QCD CR b-CR Z Z -CR Data 161 213 141 52 Total predicted 167 ± 11 204 ± 12 146 ± 11 51.3 ± 7.0 W Z j j −EW (signal) 44 ± 11 8.52 ± 0.41 1.38 ± 0.10 0.211 ± 0.004 W Z j j −QCD 91 ± 10 144 ± 14 13.9 ± 3.8 0.94 ± 0.14 Misid. leptons 7.8 ± 3.2 14.0 ± 5.7 23.5 ± 9.6 0.41 ± 0.18 Z Z j j −QCD 11.1 ± 2.8 18.3 ± 1.1 2.35 ± 0.06 40.8 ± 7.2 tZj 6.2 ± 1.1 6.3 ± 1.1 34.0 ± 5.3 0.17 ± 0.04 t t̄ + V 4.7 ± 1.0 11.14 ± 0.37 71 ± 15 3.47 ± 0.54 Z Z j j −EW 1.80 ± 0.45 0.44 ± 0.10 0.10 ± 0.03 4.2 ± 1.2 VVV 0.59 ± 0.15 0.93 ± 0.23 0.13 ± 0.03 1.06 ± 0.30 where the uncertainties correspond to statistical, experimental 5.3 standard deviations, compared with 3.2 standard deviations systematic, theory modelling and interference systematic, theory expected. The normalisation parameters of the W Z j j −QCD, t t̄ + V fid., MC σW Z j j −EW normalisation and luminosity uncertainties, respectively. and Z Z backgrounds constrained by data in the control and sig- The background-only hypothesis is excluded with a significance of nal regions are measured to be μW Z j j−QCD = 0.56 ± 0.16, μtt̄ + V = 476 The ATLAS Collaboration / Physics Letters B 793 (2019) 469–492 1.07 ± 0.28 and μ Z Z j j −QCD = 1.34 ± 0.44. The observed W Z j j −EW The measured W ± Z j j cross-section in the fiducial phase space production integrated fiducial cross-section derived from this sig- for a single leptonic decay mode is nal strength for a single leptonic decay mode is fid. σW ± Z j j = 1.68 ± 0.16 (stat.) ± 0.12 (exp. syst.) fid. +0.14 +0.05 σW Z j j −EW = 0.57 −0.13 (stat.) −0.04 (exp. syst.) ± 0.13 (mod. syst.) ± 0.044 (lumi.) fb , +0.05 +0.01 = 1.68 ± 0.25 fb , −0.04 (mod. syst.) −0.01 (lumi.) fb where the uncertainties correspond to statistical, experimental sys- = 0.57 + 0.16 −0.14 fb . tematic, theory modelling systematic, and luminosity uncertain- ties, respectively. The corresponding prediction from Sherpa for It corresponds to the cross-section of electroweak W ± Z j j pro- strong and electroweak production without interference effects duction, including interference effects between W Z j j −QCD and is W Z j j −EW processes, in the fiducial phase space defined in Sec- = 2.15 ± 0.01 (stat.) ± 0.05 (PDF)+ tion 3 using dressed-level leptons. fid., Sherpa 0.65 σW ± Z jj −0.44 (scale) fb. The SM LO prediction from Sherpa for electroweak production without interference effects is Events in the SR are also used to measure the W ± Z j j differen- tial production cross-section in the VBS fiducial phase space. The differential detector-level distributions are corrected for detector = 0.321 ± 0.002 (stat.) ± 0.005 (PDF)+ fid., Sherpa 0.027 σW Z j j −EW −0.023 (scale) fb, resolution using an iterative Bayesian unfolding method [65], as implemented in the RooUnfold toolkit [66]. Three iterations were where the effects of uncertainties in the PDF and the αS value used for the unfolding of each variable. The width of the bins in used in the PDF determination, as well as the uncertainties due each distribution is chosen according to the experimental resolu- to the renormalisation and factorisation scales, are evaluated using tion and to the statistical significance of the expected number of the same procedure as the one described in Section 8. events in that bin. The fraction of signal MC events reconstructed fid., MadGraph A larger cross-section of σ W Z j j −EW = 0.366 ± 0.004 (stat.) fb in the same bin as generated is always greater than 40% and is predicted by MadGraph. These predictions are at LO only and around 70% on average. include neither the effects of interference, estimated at LO to be For each distribution, simulated W ± Z j j events are used to 10%, nor the effects of NLO electroweak corrections as calculated obtain a response matrix that accounts for bin-to-bin migration recently in Ref. [64]. effects between the reconstruction-level and particle-level distri- From the number of observed events in the SR, the integrated butions. The Sherpa MC samples for W Z j j −EW and W Z j j −QCD cross-section of W ± Z j j production in the VBS fiducial phase space production are added together to model W ± Z j j production. To defined in Section 3, including W Z j j −EW and W Z j j −QCD con- more closely model the data and to minimise unfolding uncer- tainties, their predicted cross-sections are rescaled by the respec- tributions and their interference, is measured. For a given channel tive signal strengths of 1.77 and 0.56 for the W Z j j −EW and W ± Z → ± ν + − , where and  indicates each type of lep- W Z j j −QCD contributions, respectively, as measured in data by the ton (e or μ), the integrated fiducial cross section that includes the maximum-likelihood fit. leptonic branching fractions of the W and Z bosons is calculated Uncertainties in the unfolding due to imperfect modelling of as the data by the MC simulation are evaluated using a data-driven   method [67], where the MC differential distribution is corrected to fid. N data − N bkg Nτ match the data distribution and the resulting weighted MC distri- σW ± Z jj = × 1− , L · CW Z jj N all bution at reconstruction level is unfolded with the response matrix used in the data unfolding. The new unfolded distribution is com- where N data and N bkg are the number of observed events and pared with the weighted MC distribution at generator level and the the estimated number of background events in the SR, respec- difference is taken as the systematic uncertainty. The uncertainties tively, and L is the integrated luminosity. The factor C W Z j j , ob- obtained range from 0.1% to 25% depending on the resolution of tained from simulation, is the ratio of the number of selected the unfolded observables and on the quality of its description by signal events at detector level to the number of events at particle Sherpa. level in the fiducial phase space. This factor corrects for detector Measurements are performed as a function of three variables efficiencies and for QED final-state radiation effects. The contribu- sensitive to anomalies in the quartic gauge coupling in W ± Z j j tion from τ -lepton decays, amounting to 4.7%, is removed from events [10], namely the scalar sum of the transverse momenta of the cross-section definition by introducing the term in parenthe- the  three charged leptons associated with the W and Z bosons ses. This term is computed using simulation, where N τ is the p T , the difference in azimuthal angle φ( W , Z ) between the number of selected events at detector level in which at least W and Z bosons’ directions, and the transverse mass of the W ± Z one of the bosons decays into a τ -lepton and N all is the num- system mTW Z , defined following Ref. [10]. These are presented in ber of selected W Z events with decays into any lepton. The Fig. 3. C W Z j j factor calculated with Sherpa for the sum of the four mea- Measurements are also performed as a function of variables sured decay channels is 0.52 with a negligible statistical uncer- related to the kinematics of jets. The exclusive multiplicity of tainty. This factor is the same for W Z j j −QCD and W Z j j −EW jets, N jets , is shown in Fig. 4. The absolute difference in rapid- events, as predicted by Sherpa. The theory modelling uncertainty ity between the two tagging jets y j j , the invariant mass of gap in this factor is 8%, as estimated from the difference between the tagging jets m j j , the exclusive multiplicity N jets of jets with the Sherpa and MadGraph predictions. The uncertainties on this p T > 25 GeV in the gap in η between the two tagging jets, and factor due to higher order QCD scale corrections or PDF are negli- the azimuthal angle between the two tagging jets φ j j are shown gible. in Fig. 5. The ATLAS Collaboration / Physics Letters B 793 (2019) 469–492 477  Fig. 3. The measured W ± Z j j differential cross-section in the VBS fiducial phase space as a function of (a) p T , (b) φ( W , Z ) and (c) mTW Z . The inner and outer error bars on the data points represent the statistical and total uncertainties, respectively. The measurements are compared with the sum of the rescaled W Z j j −QCD and W Z j j −EW predictions from Sherpa (solid line). The W Z j j −EW and W Z j j −QCD contributions are also represented by dashed and dashed-dotted lines, respectively. In (a) and (c), the right y-axis refers to the last cross-section point, separated from the others by a vertical dashed line, as this last bin is integrated up to the maximum value reached in the phase space. The lower panels show the ratios of the data to the predictions from Sherpa. The uncertainty on the Sherpa prediction is dominated by the QCD scale uncertainty on the W Z j j −QCD predicted cross-section, whose envelope is of + 30 −20 % and it is not represented on the figure. Total uncertainties in the measurements are dominated by sta- the detector acceptance that increases the sensitivity to W ± Z j j tistical uncertainties. The differential measurements are compared electroweak production modes. with the prediction from Sherpa, after having rescaled the separate The electroweak production of W ± Z bosons in association with W Z j j −QCD and W Z j j −EW components by the global μ W Z j j −QCD two jets is measured with observed and expected significances of and μ W Z j j −EW parameters, respectively, obtained from the profile- 5.3 and 3.2 standard deviations, respectively. The measured fidu- likelihood fit to data. Interference effects between the W Z j j −QCD cial cross-section for electroweak production including interference and W Z j j −EW processes are incorporated via the μ W Z j j −EW pa- effects is rameter as a change of the global normalisation of the Sherpa elec- troweak prediction. σW Z j j−EW = 0.57 + 0.14 +0.05 −0.13 (stat.)−0.04 (exp. syst.) 10. Conclusion +0.05 +0.01 −0.04 (mod. syst.) −0.01 (lumi.) fb. An observation of electroweak production of a diboson W ± Z It is found to be larger than the LO SM prediction of 0.32 ± 0.03 fb system in association with as calculated with the Sherpa MC event generator that includes √ two jets and measurements of its pro- duction cross-section in s = 13 TeV pp collisions at the LHC are neither interference effects, estimated at LO to be 10%, nor NLO presented. The data were collected with the ATLAS detector and electroweak corrections. Differential cross-sections of W ± Z j j pro- correspond to an integrated luminosity of 36.1 fb−1 . 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Djuvsland 60a , M.A.B. Do Vale 79c , M. Dobre 27b , D. Dodsworth 26 , C. Doglioni 95 , J. Dolejsi 142 , Z. Dolezal 142 , M. Donadelli 79d , J. Donini 38 , A. D’onofrio 91 , M. D’Onofrio 89 , J. Dopke 143 , A. Doria 68a , M.T. Dova 87 , A.T. Doyle 56 , E. Drechsler 52 , E. Dreyer 151 , T. Dreyer 52 , Y. Du 59b , F. Dubinin 109 , M. Dubovsky 28a , A. Dubreuil 53 , E. Duchovni 179 , G. Duckeck 113 , A. Ducourthial 135 , O.A. Ducu 108,v , D. Duda 114 , A. Dudarev 36 , A.C. Dudder 98 , E.M. Duffield 18 , L. Duflot 131 , M. Dührssen 36 , C. Dülsen 181 , M. Dumancic 179 , A.E. Dumitriu 27b,d , A.K. Duncan 56 , M. Dunford 60a , A. Duperrin 100 , H. Duran Yildiz 4a , M. Düren 55 , A. Durglishvili 158b , D. Duschinger 47 , B. Dutta 45 , D. Duvnjak 1 , M. Dyndal 45 , S. Dysch 99 , B.S. Dziedzic 83 , C. Eckardt 45 , K.M. Ecker 114 , R.C. Edgar 104 , T. Eifert 36 , G. Eigen 17 , K. Einsweiler 18 , T. Ekelof 171 , M. El Kacimi 35c , R. El Kosseifi 100 , V. Ellajosyula 100 , M. Ellert 171 , F. Ellinghaus 181 , A.A. Elliot 91 , N. Ellis 36 , J. Elmsheuser 29 , M. Elsing 36 , D. Emeliyanov 143 , A. Emerman 39 , Y. Enari 162 , J.S. Ennis 177 , M.B. Epland 48 , J. Erdmann 46 , A. Ereditato 20 , S. Errede 172 , M. Escalier 131 , C. Escobar 173 , O. Estrada Pastor 173 , A.I. Etienvre 144 , E. Etzion 160 , H. Evans 64 , A. Ezhilov 137 , M. Ezzi 35e , F. Fabbri 56 , L. Fabbri 23b,23a , V. Fabiani 118 , G. Facini 93 , R.M. Faisca Rodrigues Pereira 139a , R.M. Fakhrutdinov 122 , S. Falciano 71a , P.J. Falke 5 , S. Falke 5 , J. Faltova 142 , Y. Fang 15a , M. Fanti 67a,67b , A. Farbin 8 , A. Farilla 73a , E.M. Farina 69a,69b , T. Farooque 105 , S. Farrell 18 , S.M. Farrington 177 , P. Farthouat 36 , F. Fassi 35e , P. Fassnacht 36 , D. Fassouliotis 9 , M. Faucci Giannelli 49 , A. Favareto 54b,54a , W.J. Fawcett 32 , L. Fayard 131 , O.L. Fedin 137,o , W. Fedorko 174 , M. Feickert 42 , S. Feigl 133 , L. Feligioni 100 , C. Feng 59b , E.J. Feng 36 , M. Feng 48 , M.J. Fenton 56 , A.B. Fenyuk 122 , L. Feremenga 8 , J. Ferrando 45 , A. Ferrari 171 , P. Ferrari 119 , R. Ferrari 69a , D.E. Ferreira de Lima 60b , A. Ferrer 173 , D. Ferrere 53 , C. Ferretti 104 , F. Fiedler 98 , A. Filipčič 90 , F. Filthaut 118 , K.D. Finelli 25 , M.C.N. Fiolhais 139a,139c,a , L. Fiorini 173 , C. Fischer 14 , W.C. Fisher 105 , N. Flaschel 45 , I. Fleck 150 , P. Fleischmann 104 , R.R.M. Fletcher 136 , T. Flick 181 , B.M. Flierl 113 , L.F. Flores 136 , L.R. Flores Castillo 62a , F.M. Follega 74a,74b , N. Fomin 17 , G.T. Forcolin 74a,74b , A. Formica 144 , F.A. Förster 14 , The ATLAS Collaboration / Physics Letters B 793 (2019) 469–492 483 A.C. Forti 99 , A.G. Foster 21 , D. Fournier 131 , H. Fox 88 , S. Fracchia 148 , P. Francavilla 70a,70b , M. Franchini 23b,23a , S. Franchino 60a , D. Francis 36 , L. Franconi 145 , M. Franklin 58 , M. Frate 170 , M. Fraternali 69a,69b , A.N. Fray 91 , D. Freeborn 93 , S.M. Fressard-Batraneanu 36 , B. Freund 108 , W.S. Freund 79b , E.M. Freundlich 46 , D.C. Frizzell 127 , D. Froidevaux 36 , J.A. Frost 134 , C. Fukunaga 163 , E. Fullana Torregrosa 173 , T. Fusayasu 115 , J. Fuster 173 , O. Gabizon 159 , A. Gabrielli 23b,23a , A. Gabrielli 18 , G.P. Gach 82a , S. Gadatsch 53 , P. Gadow 114 , G. Gagliardi 54b,54a , L.G. Gagnon 108 , C. Galea 27b , B. Galhardo 139a,139c , E.J. Gallas 134 , B.J. Gallop 143 , P. Gallus 141 , G. Galster 40 , R. Gamboa Goni 91 , K.K. Gan 125 , S. Ganguly 179 , J. Gao 59a , Y. Gao 89 , Y.S. Gao 31,l , C. García 173 , J.E. García Navarro 173 , J.A. García Pascual 15a , M. Garcia-Sciveres 18 , R.W. Gardner 37 , N. Garelli 152 , V. Garonne 133 , K. Gasnikova 45 , A. Gaudiello 54b,54a , G. Gaudio 69a , I.L. Gavrilenko 109 , A. Gavrilyuk 110 , C. Gay 174 , G. Gaycken 24 , E.N. Gazis 10 , C.N.P. Gee 143 , J. Geisen 52 , M. Geisen 98 , M.P. Geisler 60a , K. Gellerstedt 44a,44b , C. Gemme 54b , M.H. Genest 57 , C. Geng 104 , S. Gentile 71a,71b , S. George 92 , D. Gerbaudo 14 , G. Gessner 46 , S. 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Gutelman 159 , P. Gutierrez 127 , C. Gutschow 93 , C. Guyot 144 , M.P. Guzik 82a , C. Gwenlan 134 , C.B. Gwilliam 89 , A. Haas 123 , C. Haber 18 , H.K. Hadavand 8 , N. Haddad 35e , A. Hadef 59a , S. Hageböck 24 , M. Hagihara 168 , H. Hakobyan 183,∗ , M. Haleem 176 , J. Haley 128 , G. Halladjian 105 , G.D. Hallewell 100 , K. Hamacher 181 , P. Hamal 129 , K. Hamano 175 , A. Hamilton 33a , G.N. Hamity 148 , K. Han 59a,ae , L. Han 59a , S. Han 15a,15d , K. Hanagaki 80,t , M. Hance 145 , D.M. Handl 113 , B. Haney 136 , R. Hankache 135 , P. Hanke 60a , E. Hansen 95 , J.B. Hansen 40 , J.D. Hansen 40 , M.C. Hansen 24 , P.H. Hansen 40 , E.C. Hanson 99 , K. Hara 168 , A.S. Hard 180 , T. Harenberg 181 , S. Harkusha 106 , P.F. Harrison 177 , N.M. Hartmann 113 , Y. Hasegawa 149 , A. Hasib 49 , S. Hassani 144 , S. Haug 20 , R. Hauser 105 , L. Hauswald 47 , L.B. Havener 39 , M. Havranek 141 , C.M. Hawkes 21 , R.J. Hawkings 36 , D. Hayden 105 , C. Hayes 154 , C.P. Hays 134 , J.M. Hays 91 , H.S. Hayward 89 , S.J. Haywood 143 , M.P. Heath 49 , V. Hedberg 95 , L. Heelan 8 , S. Heer 24 , K.K. Heidegger 51 , J. Heilman 34 , S. Heim 45 , T. Heim 18 , B. Heinemann 45,al , J.J. Heinrich 113 , L. Heinrich 123 , C. Heinz 55 , J. Hejbal 140 , L. Helary 36 , A. Held 174 , S. Hellesund 133 , S. Hellman 44a,44b , C. Helsens 36 , R.C.W. Henderson 88 , Y. Heng 180 , S. Henkelmann 174 , A.M. Henriques Correia 36 , G.H. Herbert 19 , H. Herde 26 , V. Herget 176 , Y. Hernández Jiménez 33c , H. Herr 98 , M.G. Herrmann 113 , T. Herrmann 47 , G. Herten 51 , R. Hertenberger 113 , L. Hervas 36 , T.C. Herwig 136 , G.G. Hesketh 93 , N.P. Hessey 167a , A. Higashida 162 , S. Higashino 80 , E. Higón-Rodriguez 173 , K. Hildebrand 37 , E. Hill 175 , J.C. Hill 32 , K.K. Hill 29 , K.H. Hiller 45 , S.J. Hillier 21 , M. Hils 47 , I. Hinchliffe 18 , M. Hirose 132 , D. Hirschbuehl 181 , B. Hiti 90 , O. Hladik 140 , D.R. Hlaluku 33c , X. Hoad 49 , J. Hobbs 154 , N. Hod 167a , M.C. Hodgkinson 148 , A. Hoecker 36 , M.R. Hoeferkamp 117 , F. Hoenig 113 , D. Hohn 24 , D. Hohov 131 , T.R. Holmes 37 , M. Holzbock 113 , M. Homann 46 , S. Honda 168 , T. Honda 80 , T.M. Hong 138 , A. Hönle 114 , B.H. Hooberman 172 , W.H. Hopkins 130 , Y. Horii 116 , P. Horn 47 , A.J. Horton 151 , L.A. Horyn 37 , J-Y. Hostachy 57 , A. Hostiuc 147 , S. Hou 157 , A. Hoummada 35a , J. Howarth 99 , J. Hoya 87 , M. Hrabovsky 129 , J. Hrdinka 36 , I. Hristova 19 , 484 The ATLAS Collaboration / Physics Letters B 793 (2019) 469–492 J. Hrivnac 131 , A. Hrynevich 107 , T. Hryn’ova 5 , P.J. Hsu 63 , S.-C. Hsu 147 , Q. Hu 29 , S. Hu 59c , Y. Huang 15a , Z. Hubacek 141 , F. Hubaut 100 , M. Huebner 24 , F. Huegging 24 , T.B. Huffman 134 , M. Huhtinen 36 , R.F.H. Hunter 34 , P. Huo 154 , A.M. Hupe 34 , N. Huseynov 78,ac , J. Huston 105 , J. Huth 58 , R. Hyneman 104 , G. Iacobucci 53 , G. Iakovidis 29 , I. Ibragimov 150 , L. Iconomidou-Fayard 131 , Z. Idrissi 35e , P.I. Iengo 36 , R. Ignazzi 40 , O. Igonkina 119,y , R. Iguchi 162 , T. Iizawa 53 , Y. Ikegami 80 , M. Ikeno 80 , D. Iliadis 161 , N. Ilic 118 , F. Iltzsche 47 , G. Introzzi 69a,69b , M. Iodice 73a , K. Iordanidou 39 , V. Ippolito 71a,71b , M.F. Isacson 171 , N. Ishijima 132 , M. Ishino 162 , M. Ishitsuka 164 , W. Islam 128 , C. Issever 134 , S. Istin 159 , F. Ito 168 , J.M. Iturbe Ponce 62a , R. Iuppa 74a,74b , A. Ivina 179 , H. Iwasaki 80 , J.M. Izen 43 , V. Izzo 68a , P. Jacka 140 , P. Jackson 1 , R.M. Jacobs 24 , V. Jain 2 , G. Jäkel 181 , K.B. Jakobi 98 , K. Jakobs 51 , S. Jakobsen 75 , T. Jakoubek 140 , D.O. Jamin 128 , R. Jansky 53 , J. Janssen 24 , M. Janus 52 , P.A. Janus 82a , G. Jarlskog 95 , N. Javadov 78,ac , T. Javůrek 36 , M. Javurkova 51 , F. Jeanneau 144 , L. Jeanty 18 , J. Jejelava 158a,ad , A. Jelinskas 177 , P. Jenni 51,c , J. Jeong 45 , N. Jeong 45 , S. Jézéquel 5 , H. Ji 180 , J. Jia 154 , H. Jiang 77 , Y. Jiang 59a , Z. Jiang 152 , S. Jiggins 51 , F.A. Jimenez Morales 38 , J. Jimenez Pena 173 , S. Jin 15c , A. Jinaru 27b , O. Jinnouchi 164 , H. Jivan 33c , P. Johansson 148 , K.A. Johns 7 , C.A. Johnson 64 , W.J. Johnson 147 , K. Jon-And 44a,44b , R.W.L. Jones 88 , S.D. Jones 155 , S. Jones 7 , T.J. Jones 89 , J. Jongmanns 60a , P.M. Jorge 139a,139b , J. Jovicevic 167a , X. Ju 18 , J.J. Junggeburth 114 , A. Juste Rozas 14,x , A. Kaczmarska 83 , M. Kado 131 , H. Kagan 125 , M. Kagan 152 , T. Kaji 178 , E. Kajomovitz 159 , C.W. Kalderon 95 , A. Kaluza 98 , S. Kama 42 , A. Kamenshchikov 122 , L. Kanjir 90 , Y. Kano 162 , V.A. Kantserov 111 , J. Kanzaki 80 , B. Kaplan 123 , L.S. Kaplan 180 , D. Kar 33c , M.J. Kareem 167b , E. Karentzos 10 , S.N. Karpov 78 , Z.M. Karpova 78 , V. Kartvelishvili 88 , A.N. Karyukhin 122 , L. Kashif 180 , R.D. Kass 125 , A. Kastanas 44a,44b , Y. Kataoka 162 , C. Kato 59d,59c , J. Katzy 45 , K. Kawade 81 , K. Kawagoe 86 , T. Kawamoto 162 , G. Kawamura 52 , E.F. Kay 89 , V.F. Kazanin 121b,121a , R. Keeler 175 , R. Kehoe 42 , J.S. Keller 34 , E. Kellermann 95 , J.J. Kempster 21 , J. Kendrick 21 , O. Kepka 140 , S. Kersten 181 , B.P. Kerševan 90 , S. Ketabchi Haghighat 166 , R.A. Keyes 102 , M. Khader 172 , F. Khalil-Zada 13 , A. Khanov 128 , A.G. Kharlamov 121b,121a , T. Kharlamova 121b,121a , E.E. Khoda 174 , A. Khodinov 165 , T.J. Khoo 53 , E. Khramov 78 , J. Khubua 158b , S. Kido 81 , M. Kiehn 53 , C.R. Kilby 92 , Y.K. Kim 37 , N. Kimura 65a,65c , O.M. Kind 19 , B.T. King 89,∗ , D. Kirchmeier 47 , J. Kirk 143 , A.E. Kiryunin 114 , T. Kishimoto 162 , D. Kisielewska 82a , V. Kitali 45 , O. Kivernyk 5 , E. Kladiva 28b,∗ , T. Klapdor-Kleingrothaus 51 , M.H. Klein 104 , M. Klein 89 , U. Klein 89 , K. Kleinknecht 98 , P. Klimek 120 , A. Klimentov 29 , T. Klingl 24 , T. Klioutchnikova 36 , F.F. Klitzner 113 , P. Kluit 119 , S. Kluth 114 , E. Kneringer 75 , E.B.F.G. Knoops 100 , A. Knue 51 , A. Kobayashi 162 , D. Kobayashi 86 , T. Kobayashi 162 , M. Kobel 47 , M. Kocian 152 , P. Kodys 142 , P.T. Koenig 24 , T. Koffas 34 , E. Koffeman 119 , N.M. Köhler 114 , T. Koi 152 , M. Kolb 60b , I. Koletsou 5 , T. Kondo 80 , N. Kondrashova 59c , K. Köneke 51 , A.C. König 118 , T. Kono 124 , R. Konoplich 123,ah , V. Konstantinides 93 , N. Konstantinidis 93 , B. Konya 95 , R. Kopeliansky 64 , S. Koperny 82a , K. Korcyl 83 , K. Kordas 161 , G. Koren 160 , A. Korn 93 , I. Korolkov 14 , E.V. Korolkova 148 , N. Korotkova 112 , O. Kortner 114 , S. Kortner 114 , T. Kosek 142 , V.V. Kostyukhin 24 , A. Kotwal 48 , A. Koulouris 10 , A. Kourkoumeli-Charalampidi 69a,69b , C. Kourkoumelis 9 , E. Kourlitis 148 , V. Kouskoura 29 , A.B. Kowalewska 83 , R. Kowalewski 175 , T.Z. Kowalski 82a , C. Kozakai 162 , W. Kozanecki 144 , A.S. Kozhin 122 , V.A. Kramarenko 112 , G. Kramberger 90 , D. Krasnopevtsev 59a , M.W. Krasny 135 , A. Krasznahorkay 36 , D. Krauss 114 , J.A. Kremer 82a , J. Kretzschmar 89 , P. Krieger 166 , K. Krizka 18 , K. Kroeninger 46 , H. Kroha 114 , J. Kroll 140 , J. Kroll 136 , J. Krstic 16 , U. Kruchonak 78 , H. Krüger 24 , N. Krumnack 77 , M.C. Kruse 48 , T. Kubota 103 , S. Kuday 4b , J.T. Kuechler 181 , S. Kuehn 36 , A. Kugel 60a , F. Kuger 176 , T. Kuhl 45 , V. Kukhtin 78 , R. Kukla 100 , Y. Kulchitsky 106 , S. Kuleshov 146b , Y.P. Kulinich 172 , M. Kuna 57 , T. Kunigo 84 , A. Kupco 140 , T. Kupfer 46 , O. Kuprash 160 , H. Kurashige 81 , L.L. Kurchaninov 167a , Y.A. Kurochkin 106 , A. Kurova 111 , M.G. Kurth 15a,15d , E.S. Kuwertz 36 , M. Kuze 164 , J. Kvita 129 , T. Kwan 102 , A. La Rosa 114 , J.L. La Rosa Navarro 79d , L. La Rotonda 41b,41a , F. La Ruffa 41b,41a , C. Lacasta 173 , F. Lacava 71a,71b , J. Lacey 45 , D.P.J. Lack 99 , H. Lacker 19 , D. Lacour 135 , E. Ladygin 78 , R. Lafaye 5 , B. Laforge 135 , T. Lagouri 33c , S. Lai 52 , S. Lammers 64 , W. Lampl 7 , E. Lançon 29 , U. Landgraf 51 , M.P.J. Landon 91 , M.C. Lanfermann 53 , V.S. Lang 45 , J.C. Lange 52 , R.J. Langenberg 36 , A.J. Lankford 170 , F. Lanni 29 , K. Lantzsch 24 , A. Lanza 69a , A. Lapertosa 54b,54a , S. Laplace 135 , J.F. Laporte 144 , T. Lari 67a , F. Lasagni Manghi 23b,23a , M. Lassnig 36 , T.S. Lau 62a , A. Laudrain 131 , M. Lavorgna 68a,68b , M. Lazzaroni 67a,67b , B. Le 103 , O. Le Dortz 135 , E. Le Guirriec 100 , E.P. Le Quilleuc 144 , M. LeBlanc 7 , T. LeCompte 6 , F. Ledroit-Guillon 57 , C.A. Lee 29 , G.R. Lee 146a , L. Lee 58 , S.C. Lee 157 , B. Lefebvre 102 , M. Lefebvre 175 , F. Legger 113 , C. Leggett 18 , K. Lehmann 151 , N. Lehmann 181 , G. Lehmann Miotto 36 , The ATLAS Collaboration / Physics Letters B 793 (2019) 469–492 485 W.A. Leight 45 , A. Leisos 161,u , M.A.L. Leite 79d , R. Leitner 142 , D. Lellouch 179,∗ , K.J.C. Leney 93 , T. Lenz 24 , B. Lenzi 36 , R. Leone 7 , S. Leone 70a , C. Leonidopoulos 49 , G. Lerner 155 , C. Leroy 108 , R. Les 166 , A.A.J. Lesage 144 , C.G. Lester 32 , M. Levchenko 137 , J. Levêque 5 , D. Levin 104 , L.J. Levinson 179 , D. Lewis 91 , B. Li 15b , B. Li 104 , C-Q. Li 59a,ag , H. Li 59b , L. Li 59c , M. Li 15a , Q. Li 15a,15d , Q.Y. Li 59a , S. 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Love 88 , J.J. Lozano Bahilo 173 , H. Lu 62a , M. Lu 59a , N. Lu 104 , Y.J. Lu 63 , H.J. Lubatti 147 , C. Luci 71a,71b , A. Lucotte 57 , C. Luedtke 51 , F. Luehring 64 , I. Luise 135 , L. Luminari 71a , B. Lund-Jensen 153 , M.S. Lutz 101 , P.M. Luzi 135 , D. Lynn 29 , R. Lysak 140 , E. Lytken 95 , F. Lyu 15a , V. Lyubushkin 78 , T. Lyubushkina 78 , H. Ma 29 , L.L. Ma 59b , Y. Ma 59b , G. Maccarrone 50 , A. Macchiolo 114 , C.M. Macdonald 148 , J. Machado Miguens 136,139b , D. Madaffari 173 , R. Madar 38 , W.F. Mader 47 , A. Madsen 45 , N. Madysa 47 , J. Maeda 81 , K. Maekawa 162 , S. Maeland 17 , T. Maeno 29 , M. Maerker 47 , A.S. Maevskiy 112 , V. Magerl 51 , D.J. Mahon 39 , C. Maidantchik 79b , T. Maier 113 , A. Maio 139a,139b,139d , O. Majersky 28a , S. Majewski 130 , Y. Makida 80 , N. Makovec 131 , B. Malaescu 135 , Pa. Malecki 83 , V.P. Maleev 137 , F. Malek 57 , U. Mallik 76 , D. Malon 6 , C. Malone 32 , S. Maltezos 10 , S. Malyukov 36 , J. Mamuzic 173 , G. Mancini 50 , I. Mandić 90 , J. Maneira 139a , L. Manhaes de Andrade Filho 79a , J. Manjarres Ramos 47 , K.H. Mankinen 95 , A. Mann 113 , A. Manousos 75 , B. Mansoulie 144 , J.D. Mansour 15a , M. Mantoani 52 , S. Manzoni 67a,67b , A. Marantis 161 , G. Marceca 30 , L. March 53 , L. Marchese 134 , G. Marchiori 135 , M. Marcisovsky 140 , C.A. Marin Tobon 36 , M. Marjanovic 38 , D.E. Marley 104 , F. Marroquim 79b , Z. Marshall 18 , M.U.F. Martensson 171 , S. Marti-Garcia 173 , C.B. Martin 125 , T.A. Martin 177 , V.J. Martin 49 , B. Martin dit Latour 17 , M. Martinez 14,x , V.I. Martinez Outschoorn 101 , S. Martin-Haugh 143 , V.S. Martoiu 27b , A.C. Martyniuk 93 , A. Marzin 36 , L. Masetti 98 , T. Mashimo 162 , R. Mashinistov 109 , J. Masik 99 , A.L. Maslennikov 121b,121a , L.H. Mason 103 , L. Massa 72a,72b , P. Massarotti 68a,68b , P. Mastrandrea 5 , A. Mastroberardino 41b,41a , T. Masubuchi 162 , P. Mättig 181 , J. Maurer 27b , B. Maček 90 , S.J. Maxfield 89 , D.A. Maximov 121b,121a , R. Mazini 157 , I. Maznas 161 , S.M. Mazza 145 , G. Mc Goldrick 166 , S.P. Mc Kee 104 , T.G. McCarthy 114 , L.I. McClymont 93 , E.F. McDonald 103 , J.A. Mcfayden 36 , M.A. McKay 42 , K.D. McLean 175 , S.J. McMahon 143 , P.C. McNamara 103 , C.J. McNicol 177 , R.A. McPherson 175,aa , J.E. Mdhluli 33c , Z.A. Meadows 101 , S. Meehan 147 , T. Megy 51 , S. Mehlhase 113 , A. Mehta 89 , T. Meideck 57 , B. Meirose 43 , D. Melini 173,ar , B.R. Mellado Garcia 33c , J.D. Mellenthin 52 , M. Melo 28a , F. Meloni 45 , A. Melzer 24 , S.B. Menary 99 , E.D. Mendes Gouveia 139a , L. Meng 89 , X.T. Meng 104 , A. Mengarelli 23b,23a , S. Menke 114 , E. Meoni 41b,41a , S. Mergelmeyer 19 , S.A.M. Merkt 138 , C. Merlassino 20 , P. Mermod 53 , L. Merola 68a,68b , C. Meroni 67a , F.S. Merritt 37 , A. Messina 71a,71b , J. Metcalfe 6 , A.S. Mete 170 , C. Meyer 136 , J. Meyer 159 , J-P. Meyer 144 , H. Meyer Zu Theenhausen 60a , F. Miano 155 , R.P. Middleton 143 , L. Mijović 49 , G. Mikenberg 179 , M. Mikestikova 140 , M. Mikuž 90 , M. Milesi 103 , A. Milic 166 , D.A. Millar 91 , D.W. Miller 37 , A. Milov 179 , D.A. Milstead 44a,44b , A.A. Minaenko 122 , M. Miñano Moya 173 , I.A. Minashvili 158b , A.I. Mincer 123 , B. Mindur 82a , M. Mineev 78 , Y. Minegishi 162 , Y. Ming 180 , L.M. Mir 14 , A. Mirto 66a,66b , K.P. Mistry 136 , T. Mitani 178 , J. Mitrevski 113 , V.A. Mitsou 173 , M. Mittal 59c , A. Miucci 20 , P.S. Miyagawa 148 , A. Mizukami 80 , J.U. Mjörnmark 95 , T. Mkrtchyan 183 , M. Mlynarikova 142 , T. Moa 44a,44b , K. Mochizuki 108 , P. Mogg 51 , S. Mohapatra 39 , S. Molander 44a,44b , R. Moles-Valls 24 , M.C. Mondragon 105 , K. Mönig 45 , J. Monk 40 , E. Monnier 100 , A. Montalbano 151 , J. Montejo Berlingen 36 , F. Monticelli 87 , S. Monzani 67a , N. Morange 131 , D. Moreno 22 , M. Moreno Llácer 36 , P. Morettini 54b , M. Morgenstern 119 , S. Morgenstern 47 , D. Mori 151 , M. Morii 58 , M. Morinaga 178 , V. Morisbak 133 , A.K. Morley 36 , G. Mornacchi 36 , A.P. Morris 93 , J.D. Morris 91 , L. 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Nelson 134 , S. Nemecek 140 , P. Nemethy 123 , M. Nessi 36,e , M.S. Neubauer 172 , M. Neumann 181 , P.R. Newman 21 , T.Y. Ng 62c , Y.S. Ng 19 , H.D.N. Nguyen 100 , T. Nguyen Manh 108 , E. Nibigira 38 , R.B. Nickerson 134 , R. Nicolaidou 144 , D.S. Nielsen 40 , J. Nielsen 145 , N. Nikiforou 11 , V. Nikolaenko 122,ai , I. Nikolic-Audit 135 , K. Nikolopoulos 21 , P. Nilsson 29 , Y. Ninomiya 80 , A. Nisati 71a , N. Nishu 59c , R. Nisius 114 , I. Nitsche 46 , T. Nitta 178 , T. Nobe 162 , Y. Noguchi 84 , M. Nomachi 132 , I. Nomidis 135 , M.A. Nomura 29 , T. Nooney 91 , M. Nordberg 36 , N. Norjoharuddeen 134 , T. Novak 90 , O. Novgorodova 47 , R. Novotny 141 , L. Nozka 129 , K. Ntekas 170 , E. Nurse 93 , F. Nuti 103 , F.G. Oakham 34,aq , H. Oberlack 114 , J. Ocariz 135 , A. Ochi 81 , I. Ochoa 39 , J.P. Ochoa-Ricoux 146a , K. O’Connor 26 , S. Oda 86 , S. Odaka 80 , S. Oerdek 52 , A. Oh 99 , S.H. Oh 48 , C.C. Ohm 153 , H. Oide 54b,54a , M.L. Ojeda 166 , H. Okawa 168 , Y. Okazaki 84 , Y. 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Papadopoulou 10 , K. Papageorgiou 9,h , A. Paramonov 6 , D. Paredes Hernandez 62b , S.R. Paredes Saenz 134 , B. Parida 165 , T.H. Park 34 , A.J. Parker 88 , K.A. Parker 45 , M.A. Parker 32 , F. Parodi 54b,54a , J.A. Parsons 39 , U. Parzefall 51 , V.R. Pascuzzi 166 , J.M.P. Pasner 145 , E. Pasqualucci 71a , S. Passaggio 54b , F. Pastore 92 , P. Pasuwan 44a,44b , S. Pataraia 98 , J.R. Pater 99 , A. Pathak 180 , T. Pauly 36 , B. Pearson 114 , M. Pedersen 133 , L. Pedraza Diaz 118 , R. Pedro 139a,139b , S.V. Peleganchuk 121b,121a , O. Penc 140 , C. Peng 15a , H. Peng 59a , B.S. Peralva 79a , M.M. Perego 131 , A.P. Pereira Peixoto 139a , D.V. Perepelitsa 29 , F. Peri 19 , L. Perini 67a,67b , H. Pernegger 36 , S. Perrella 68a,68b , V.D. Peshekhonov 78,∗ , K. Peters 45 , R.F.Y. Peters 99 , B.A. Petersen 36 , T.C. Petersen 40 , E. Petit 57 , A. Petridis 1 , C. Petridou 161 , P. Petroff 131 , M. Petrov 134 , F. Petrucci 73a,73b , M. Pettee 182 , N.E. Pettersson 101 , A. Peyaud 144 , R. Pezoa 146b , T. Pham 103 , F.H. Phillips 105 , P.W. Phillips 143 , M.W. Phipps 172 , G. Piacquadio 154 , E. Pianori 18 , A. Picazio 101 , M.A. Pickering 134 , R.H. Pickles 99 , R. Piegaia 30 , J.E. Pilcher 37 , A.D. Pilkington 99 , M. Pinamonti 72a,72b , J.L. Pinfold 3 , M. Pitt 179 , L. Pizzimento 72a,72b , M.-A. Pleier 29 , V. Pleskot 142 , E. Plotnikova 78 , D. Pluth 77 , P. Podberezko 121b,121a , R. Poettgen 95 , R. Poggi 53 , L. Poggioli 131 , I. Pogrebnyak 105 , D. Pohl 24 , I. Pokharel 52 , G. Polesello 69a , A. Poley 18 , A. Policicchio 71a,71b , R. Polifka 36 , A. Polini 23b , C.S. Pollard 45 , V. Polychronakos 29 , D. Ponomarenko 111 , L. Pontecorvo 36 , G.A. Popeneciu 27d , L. Portales 5 , D.M. Portillo Quintero 135 , S. Pospisil 141 , K. Potamianos 45 , I.N. Potrap 78 , C.J. Potter 32 , H. Potti 11 , T. Poulsen 95 , J. Poveda 36 , T.D. Powell 148 , M.E. Pozo Astigarraga 36 , P. Pralavorio 100 , S. Prell 77 , D. Price 99 , M. Primavera 66a , S. Prince 102 , N. Proklova 111 , K. Prokofiev 62c , F. Prokoshin 146b , S. Protopopescu 29 , J. Proudfoot 6 , M. Przybycien 82a , A. Puri 172 , P. Puzo 131 , J. Qian 104 , Y. Qin 99 , A. Quadt 52 , M. Queitsch-Maitland 45 , A. Qureshi 1 , P. Rados 103 , F. Ragusa 67a,67b , G. Rahal 96 , J.A. Raine 53 , S. Rajagopalan 29 , A. Ramirez Morales 91 , T. Rashid 131 , S. Raspopov 5 , M.G. Ratti 67a,67b , D.M. Rauch 45 , F. Rauscher 113 , S. Rave 98 , B. Ravina 148 , I. Ravinovich 179 , J.H. Rawling 99 , M. Raymond 36 , A.L. Read 133 , N.P. Readioff 57 , M. Reale 66a,66b , D.M. Rebuzzi 69a,69b , A. Redelbach 176 , G. Redlinger 29 , R. Reece 145 , R.G. Reed 33c , K. Reeves 43 , L. Rehnisch 19 , J. Reichert 136 , D. Reikher 160 , A. Reiss 98 , C. Rembser 36 , H. Ren 15a , M. Rescigno 71a , S. Resconi 67a , E.D. Resseguie 136 , S. Rettie 174 , E. Reynolds 21 , O.L. Rezanova 121b,121a , P. Reznicek 142 , E. Ricci 74a,74b , R. Richter 114 , S. Richter 45 , E. Richter-Was 82b , O. Ricken 24 , M. Ridel 135 , P. Rieck 114 , C.J. Riegel 181 , O. Rifki 45 , M. Rijssenbeek 154 , A. Rimoldi 69a,69b , M. Rimoldi 20 , L. Rinaldi 23b , G. Ripellino 153 , B. Ristić 88 , E. Ritsch 36 , I. Riu 14 , J.C. Rivera Vergara 146a , F. Rizatdinova 128 , E. Rizvi 91 , C. Rizzi 14 , R.T. Roberts 99 , S.H. Robertson 102,aa , D. Robinson 32 , J.E.M. Robinson 45 , A. Robson 56 , The ATLAS Collaboration / Physics Letters B 793 (2019) 469–492 487 E. Rocco 98 , C. Roda 70a,70b , Y. Rodina 100 , S. Rodriguez Bosca 173 , A. Rodriguez Perez 14 , D. Rodriguez Rodriguez 173 , A.M. Rodríguez Vera 167b , S. Roe 36 , C.S. Rogan 58 , O. Røhne 133 , R. Röhrig 114 , C.P.A. Roland 64 , J. Roloff 58 , A. Romaniouk 111 , M. Romano 23b,23a , N. Rompotis 89 , M. Ronzani 123 , L. Roos 135 , S. Rosati 71a , K. Rosbach 51 , N-A. Rosien 52 , B.J. Rosser 136 , E. Rossi 45 , E. Rossi 73a,73b , E. Rossi 68a,68b , L.P. Rossi 54b , L. Rossini 67a,67b , J.H.N. Rosten 32 , R. Rosten 14 , M. Rotaru 27b , J. Rothberg 147 , D. Rousseau 131 , D. Roy 33c , A. Rozanov 100 , Y. Rozen 159 , X. Ruan 33c , F. Rubbo 152 , F. Rühr 51 , A. Ruiz-Martinez 173 , Z. Rurikova 51 , N.A. Rusakovich 78 , H.L. Russell 102 , J.P. Rutherfoord 7 , E.M. Rüttinger 45,j , Y.F. Ryabov 137 , M. Rybar 172 , G. Rybkin 131 , S. Ryu 6 , A. Ryzhov 122 , G.F. Rzehorz 52 , P. Sabatini 52 , G. Sabato 119 , S. Sacerdoti 131 , H.F-W. Sadrozinski 145 , R. Sadykov 78 , F. Safai Tehrani 71a , P. Saha 120 , M. Sahinsoy 60a , A. Sahu 181 , M. Saimpert 45 , M. Saito 162 , T. Saito 162 , H. Sakamoto 162 , A. Sakharov 123,ah , D. Salamani 53 , G. Salamanna 73a,73b , J.E. Salazar Loyola 146b , P.H. Sales De Bruin 171 , D. Salihagic 114,∗ , A. Salnikov 152 , J. Salt 173 , D. Salvatore 41b,41a , F. Salvatore 155 , A. Salvucci 62a,62b,62c , A. Salzburger 36 , J. Samarati 36 , D. Sammel 51 , D. Sampsonidis 161 , D. Sampsonidou 161 , J. Sánchez 173 , A. Sanchez Pineda 65a,65c , H. Sandaker 133 , C.O. Sander 45 , M. Sandhoff 181 , C. Sandoval 22 , D.P.C. Sankey 143 , M. Sannino 54b,54a , Y. Sano 116 , A. Sansoni 50 , C. Santoni 38 , H. Santos 139a , I. Santoyo Castillo 155 , A. Santra 173 , A. Sapronov 78 , J.G. Saraiva 139a,139d , O. Sasaki 80 , K. Sato 168 , E. Sauvan 5 , P. Savard 166,aq , N. Savic 114 , R. Sawada 162 , C. Sawyer 143 , L. Sawyer 94,af , C. Sbarra 23b , A. Sbrizzi 23a , T. Scanlon 93 , J. Schaarschmidt 147 , P. Schacht 114 , B.M. Schachtner 113 , D. Schaefer 37 , L. Schaefer 136 , J. Schaeffer 98 , S. Schaepe 36 , U. Schäfer 98 , A.C. Schaffer 131 , D. Schaile 113 , R.D. Schamberger 154 , N. Scharmberg 99 , V.A. Schegelsky 137 , D. Scheirich 142 , F. Schenck 19 , M. Schernau 170 , C. Schiavi 54b,54a , S. Schier 145 , L.K. Schildgen 24 , Z.M. Schillaci 26 , E.J. Schioppa 36 , M. Schioppa 41b,41a , K.E. Schleicher 51 , S. Schlenker 36 , K.R. Schmidt-Sommerfeld 114 , K. Schmieden 36 , C. Schmitt 98 , S. Schmitt 45 , S. Schmitz 98 , J.C. Schmoeckel 45 , U. Schnoor 51 , L. Schoeffel 144 , A. Schoening 60b , E. Schopf 134 , M. Schott 98 , J.F.P. Schouwenberg 118 , J. Schovancova 36 , S. Schramm 53 , A. Schulte 98 , H-C. Schultz-Coulon 60a , M. Schumacher 51 , B.A. Schumm 145 , Ph. Schune 144 , A. Schwartzman 152 , T.A. Schwarz 104 , Ph. Schwemling 144 , R. Schwienhorst 105 , A. Sciandra 24 , G. Sciolla 26 , M. Scornajenghi 41b,41a , F. Scuri 70a , F. Scutti 103 , L.M. Scyboz 114 , C.D. Sebastiani 71a,71b , P. Seema 19 , S.C. Seidel 117 , A. Seiden 145 , T. Seiss 37 , J.M. Seixas 79b , G. Sekhniaidze 68a , K. Sekhon 104 , S.J. Sekula 42 , N. Semprini-Cesari 23b,23a , S. Sen 48 , S. Senkin 38 , C. Serfon 133 , L. Serin 131 , L. Serkin 65a,65b , M. Sessa 59a , H. Severini 127 , F. Sforza 169 , A. Sfyrla 53 , E. Shabalina 52 , J.D. Shahinian 145 , N.W. Shaikh 44a,44b , L.Y. Shan 15a , R. Shang 172 , J.T. Shank 25 , M. Shapiro 18 , A.S. Sharma 1 , A. Sharma 134 , P.B. Shatalov 110 , K. Shaw 155 , S.M. Shaw 99 , A. Shcherbakova 137 , Y. Shen 127 , N. Sherafati 34 , A.D. Sherman 25 , P. Sherwood 93 , L. Shi 157,am , S. Shimizu 80 , C.O. Shimmin 182 , Y. Shimogama 178 , M. Shimojima 115 , I.P.J. Shipsey 134 , S. Shirabe 86 , M. Shiyakova 78 , J. Shlomi 179 , A. Shmeleva 109 , D. Shoaleh Saadi 108 , M.J. Shochet 37 , S. Shojaii 103 , D.R. Shope 127 , S. Shrestha 125 , E. Shulga 111 , P. Sicho 140 , A.M. Sickles 172 , P.E. Sidebo 153 , E. Sideras Haddad 33c , O. Sidiropoulou 36 , A. Sidoti 23b,23a , F. Siegert 47 , Dj. Sijacki 16 , J. Silva 139a , M. Silva Jr. 180 , M.V. Silva Oliveira 79a , S.B. Silverstein 44a , S. Simion 131 , E. Simioni 98 , M. Simon 98 , R. Simoniello 98 , P. Sinervo 166 , N.B. Sinev 130 , M. Sioli 23b,23a , G. Siragusa 176 , I. Siral 104 , S.Yu. Sivoklokov 112 , J. Sjölin 44a,44b , P. Skubic 127 , M. Slater 21 , T. Slavicek 141 , M. Slawinska 83 , K. Sliwa 169 , R. Slovak 142 , V. Smakhtin 179 , B.H. Smart 5 , J. Smiesko 28a , N. Smirnov 111 , S.Yu. Smirnov 111 , Y. Smirnov 111 , L.N. Smirnova 112,r , O. Smirnova 95 , J.W. Smith 52 , M. Smizanska 88 , K. Smolek 141 , A. Smykiewicz 83 , A.A. Snesarev 109 , I.M. Snyder 130 , S. Snyder 29 , R. Sobie 175,aa , A.M. Soffa 170 , A. Soffer 160 , A. Søgaard 49 , D.A. Soh 157 , G. Sokhrannyi 90 , C.A. Solans Sanchez 36 , M. Solar 141 , E.Yu. Soldatov 111 , U. Soldevila 173 , A.A. Solodkov 122 , A. Soloshenko 78 , O.V. Solovyanov 122 , V. Solovyev 137 , P. Sommer 148 , H. Son 169 , W. Song 143 , W.Y. Song 167b , A. Sopczak 141 , F. Sopkova 28b , C.L. Sotiropoulou 70a,70b , S. Sottocornola 69a,69b , R. Soualah 65a,65c,g , A.M. Soukharev 121b,121a , D. South 45 , B.C. Sowden 92 , S. Spagnolo 66a,66b , M. Spalla 114 , M. Spangenberg 177 , F. Spanò 92 , D. Sperlich 19 , T.M. Spieker 60a , R. Spighi 23b , G. Spigo 36 , L.A. Spiller 103 , D.P. Spiteri 56 , M. Spousta 142 , A. Stabile 67a,67b , R. Stamen 60a , S. Stamm 19 , E. Stanecka 83 , R.W. Stanek 6 , C. Stanescu 73a , B. Stanislaus 134 , M.M. Stanitzki 45 , B. Stapf 119 , S. Stapnes 133 , E.A. Starchenko 122 , G.H. Stark 37 , J. Stark 57 , S.H. Stark 40 , P. Staroba 140 , P. Starovoitov 60a , S. Stärz 36 , R. Staszewski 83 , M. Stegler 45 , P. Steinberg 29 , B. Stelzer 151 , H.J. Stelzer 36 , O. Stelzer-Chilton 167a , H. Stenzel 55 , T.J. Stevenson 155 , G.A. Stewart 36 , M.C. Stockton 36 , 488 The ATLAS Collaboration / Physics Letters B 793 (2019) 469–492 G. Stoicea 27b , P. Stolte 52 , S. Stonjek 114 , A. Straessner 47 , J. Strandberg 153 , S. Strandberg 44a,44b , M. Strauss 127 , P. Strizenec 28b , R. Ströhmer 176 , D.M. Strom 130 , R. Stroynowski 42 , A. Strubig 49 , S.A. Stucci 29 , B. Stugu 17 , J. Stupak 127 , N.A. Styles 45 , D. Su 152 , J. Su 138 , S. Suchek 60a , Y. Sugaya 132 , M. Suk 141 , V.V. Sulin 109 , M.J. Sullivan 89 , D.M.S. Sultan 53 , S. Sultansoy 4c , T. Sumida 84 , S. Sun 104 , X. Sun 3 , K. Suruliz 155 , C.J.E. Suster 156 , M.R. Sutton 155 , S. Suzuki 80 , M. Svatos 140 , M. Swiatlowski 37 , S.P. Swift 2 , A. Sydorenko 98 , I. Sykora 28a , T. Sykora 142 , D. Ta 98 , K. Tackmann 45 , J. Taenzer 160 , A. Taffard 170 , R. Tafirout 167a , E. Tahirovic 91 , N. Taiblum 160 , H. Takai 29 , R. Takashima 85 , E.H. Takasugi 114 , K. Takeda 81 , T. Takeshita 149 , Y. Takubo 80 , M. Talby 100 , A.A. Talyshev 121b,121a , J. Tanaka 162 , M. Tanaka 164 , R. Tanaka 131 , B.B. Tannenwald 125 , S. Tapia Araya 146b , S. Tapprogge 98 , A. Tarek Abouelfadl Mohamed 135 , S. Tarem 159 , G. Tarna 27b,d , G.F. Tartarelli 67a , P. Tas 142 , M. Tasevsky 140 , T. Tashiro 84 , E. Tassi 41b,41a , A. Tavares Delgado 139a,139b , Y. Tayalati 35e , A.C. Taylor 117 , A.J. Taylor 49 , G.N. Taylor 103 , P.T.E. Taylor 103 , W. Taylor 167b , A.S. Tee 88 , P. Teixeira-Dias 92 , H. Ten Kate 36 , J.J. Teoh 119 , S. Terada 80 , K. Terashi 162 , J. Terron 97 , S. Terzo 14 , M. Testa 50 , R.J. Teuscher 166,aa , S.J. Thais 182 , T. Theveneaux-Pelzer 45 , F. Thiele 40 , D.W. Thomas 92 , J.P. Thomas 21 , A.S. Thompson 56 , P.D. Thompson 21 , L.A. Thomsen 182 , E. Thomson 136 , Y. Tian 39 , R.E. Ticse Torres 52 , V.O. Tikhomirov 109,aj , Yu.A. Tikhonov 121b,121a , S. Timoshenko 111 , P. Tipton 182 , S. Tisserant 100 , K. Todome 164 , S. Todorova-Nova 5 , S. Todt 47 , J. Tojo 86 , S. Tokár 28a , K. Tokushuku 80 , E. Tolley 125 , K.G. Tomiwa 33c , M. Tomoto 116 , L. Tompkins 152 , K. Toms 117 , B. Tong 58 , P. Tornambe 51 , E. Torrence 130 , H. Torres 47 , E. Torró Pastor 147 , C. Tosciri 134 , J. Toth 100,z , F. Touchard 100 , D.R. Tovey 148 , C.J. Treado 123 , T. Trefzger 176 , F. Tresoldi 155 , A. Tricoli 29 , I.M. Trigger 167a , S. Trincaz-Duvoid 135 , M.F. Tripiana 14 , W. Trischuk 166 , B. Trocmé 57 , A. Trofymov 131 , C. Troncon 67a , M. Trovatelli 175 , F. Trovato 155 , L. Truong 33b , M. Trzebinski 83 , A. Trzupek 83 , F. Tsai 45 , J.C-L. Tseng 134 , P.V. Tsiareshka 106 , A. Tsirigotis 161 , N. Tsirintanis 9 , V. Tsiskaridze 154 , E.G. Tskhadadze 158a , I.I. Tsukerman 110 , V. Tsulaia 18 , S. Tsuno 80 , D. Tsybychev 154 , Y. Tu 62b , A. Tudorache 27b , V. Tudorache 27b , T.T. Tulbure 27a , A.N. Tuna 58 , S. Turchikhin 78 , D. Turgeman 179 , I. Turk Cakir 4b,s , R.T. Turra 67a , P.M. Tuts 39 , E. Tzovara 98 , G. Ucchielli 23b,23a , I. Ueda 80 , M. Ughetto 44a,44b , F. Ukegawa 168 , G. Unal 36 , A. Undrus 29 , G. Unel 170 , F.C. Ungaro 103 , Y. Unno 80 , K. Uno 162 , J. Urban 28b , P. Urquijo 103 , P. Urrejola 98 , G. Usai 8 , J. Usui 80 , L. Vacavant 100 , V. Vacek 141 , B. Vachon 102 , K.O.H. Vadla 133 , A. Vaidya 93 , C. Valderanis 113 , E. Valdes Santurio 44a,44b , M. Valente 53 , S. Valentinetti 23b,23a , A. Valero 173 , L. Valéry 45 , R.A. Vallance 21 , A. Vallier 5 , J.A. Valls Ferrer 173 , T.R. Van Daalen 14 , H. Van der Graaf 119 , P. Van Gemmeren 6 , J. Van Nieuwkoop 151 , I. Van Vulpen 119 , M. Vanadia 72a,72b , W. Vandelli 36 , A. Vaniachine 165 , P. Vankov 119 , R. Vari 71a , E.W. Varnes 7 , C. Varni 54b,54a , T. Varol 42 , D. Varouchas 131 , K.E. Varvell 156 , G.A. Vasquez 146b , J.G. Vasquez 182 , F. Vazeille 38 , D. Vazquez Furelos 14 , T. Vazquez Schroeder 36 , J. Veatch 52 , V. Vecchio 73a,73b , L.M. Veloce 166 , F. Veloso 139a,139c , S. Veneziano 71a , A. Ventura 66a,66b , M. Venturi 175 , N. Venturi 36 , V. Vercesi 69a , M. Verducci 73a,73b , C.M. Vergel Infante 77 , C. Vergis 24 , W. Verkerke 119 , A.T. Vermeulen 119 , J.C. Vermeulen 119 , M.C. Vetterli 151,aq , N. Viaux Maira 146b , M. Vicente Barreto Pinto 53 , I. Vichou 172,∗ , T. Vickey 148 , O.E. Vickey Boeriu 148 , G.H.A. Viehhauser 134 , S. Viel 18 , L. Vigani 134 , M. Villa 23b,23a , M. Villaplana Perez 67a,67b , E. Vilucchi 50 , M.G. Vincter 34 , V.B. Vinogradov 78 , A. Vishwakarma 45 , C. Vittori 23b,23a , I. Vivarelli 155 , S. Vlachos 10 , M. Vogel 181 , P. Vokac 141 , G. Volpi 14 , S.E. von Buddenbrock 33c , E. Von Toerne 24 , V. Vorobel 142 , K. Vorobev 111 , M. Vos 173 , J.H. Vossebeld 89 , N. Vranjes 16 , M. Vranjes Milosavljevic 16 , V. Vrba 141 , M. Vreeswijk 119 , T. Šfiligoj 90 , R. Vuillermet 36 , I. Vukotic 37 , T. Ženiš 28a , L. Živković 16 , P. Wagner 24 , W. Wagner 181 , J. Wagner-Kuhr 113 , H. Wahlberg 87 , S. Wahrmund 47 , K. Wakamiya 81 , V.M. Walbrecht 114 , J. Walder 88 , R. Walker 113 , S.D. Walker 92 , W. Walkowiak 150 , V. Wallangen 44a,44b , A.M. Wang 58 , C. Wang 59b,d , F. Wang 180 , H. Wang 18 , H. Wang 3 , J. Wang 156 , J. Wang 60b , P. Wang 42 , Q. Wang 127 , R.-J. Wang 135 , R. Wang 59a , R. Wang 6 , S.M. Wang 157 , W.T. Wang 59a , W. Wang 15c,ab , W.X. Wang 59a,ab , Y. Wang 59a,ag , Z. Wang 59c , C. Wanotayaroj 45 , A. Warburton 102 , C.P. Ward 32 , D.R. Wardrope 93 , A. Washbrook 49 , P.M. Watkins 21 , A.T. Watson 21 , M.F. Watson 21 , G. Watts 147 , S. Watts 99 , B.M. Waugh 93 , A.F. Webb 11 , S. Webb 98 , C. Weber 182 , M.S. Weber 20 , S.A. Weber 34 , S.M. Weber 60a , A.R. Weidberg 134 , B. Weinert 64 , J. Weingarten 46 , M. Weirich 98 , C. Weiser 51 , P.S. Wells 36 , T. Wenaus 29 , T. Wengler 36 , S. Wenig 36 , N. Wermes 24 , M.D. Werner 77 , P. Werner 36 , M. Wessels 60a , T.D. Weston 20 , K. Whalen 130 , N.L. Whallon 147 , A.M. Wharton 88 , A.S. White 104 , A. White 8 , M.J. White 1 , R. White 146b , D. Whiteson 170 , The ATLAS Collaboration / Physics Letters B 793 (2019) 469–492 489 B.W. Whitmore 88 , F.J. Wickens 143 , W. Wiedenmann 180 , M. Wielers 143 , C. Wiglesworth 40 , L.A.M. Wiik-Fuchs 51 , F. Wilk 99 , H.G. Wilkens 36 , L.J. Wilkins 92 , H.H. Williams 136 , S. Williams 32 , C. Willis 105 , S. Willocq 101 , J.A. Wilson 21 , I. Wingerter-Seez 5 , E. Winkels 155 , F. Winklmeier 130 , O.J. Winston 155 , B.T. Winter 51 , M. Wittgen 152 , M. Wobisch 94 , A. Wolf 98 , T.M.H. Wolf 119 , R. Wolff 100 , M.W. Wolter 83 , H. Wolters 139a,139c , V.W.S. Wong 174 , N.L. Woods 145 , S.D. Worm 21 , B.K. Wosiek 83 , K.W. Woźniak 83 , K. Wraight 56 , M. Wu 37 , S.L. Wu 180 , X. Wu 53 , Y. Wu 59a , T.R. Wyatt 99 , B.M. Wynne 49 , S. Xella 40 , Z. Xi 104 , L. Xia 177 , D. Xu 15a , H. Xu 59a,d , L. Xu 29 , T. Xu 144 , W. Xu 104 , B. Yabsley 156 , S. Yacoob 33a , K. Yajima 132 , D.P. Yallup 93 , D. Yamaguchi 164 , Y. Yamaguchi 164 , A. Yamamoto 80 , T. Yamanaka 162 , F. Yamane 81 , M. Yamatani 162 , T. Yamazaki 162 , Y. Yamazaki 81 , Z. Yan 25 , H.J. Yang 59c,59d , H.T. Yang 18 , S. Yang 76 , Y. Yang 162 , Z. Yang 17 , W-M. Yao 18 , Y.C. Yap 45 , Y. Yasu 80 , E. Yatsenko 59c,59d , J. Ye 42 , S. Ye 29 , I. Yeletskikh 78 , E. Yigitbasi 25 , E. Yildirim 98 , K. Yorita 178 , K. Yoshihara 136 , C.J.S. Young 36 , C. Young 152 , J. Yu 8 , J. Yu 77 , X. Yue 60a , S.P.Y. Yuen 24 , B. Zabinski 83 , G. Zacharis 10 , E. Zaffaroni 53 , R. Zaidan 14 , A.M. Zaitsev 122,ai , T. Zakareishvili 158b , N. Zakharchuk 34 , J. Zalieckas 17 , S. Zambito 58 , D. Zanzi 36 , D.R. Zaripovas 56 , S.V. Zeißner 46 , C. Zeitnitz 181 , G. Zemaityte 134 , J.C. Zeng 172 , Q. Zeng 152 , O. Zenin 122 , D. Zerwas 131 , M. Zgubič 134 , D.F. Zhang 59b , D. Zhang 104 , F. Zhang 180 , G. Zhang 59a , G. Zhang 15b , H. Zhang 15c , J. Zhang 6 , L. Zhang 15c , L. Zhang 59a , M. Zhang 172 , P. Zhang 15c , R. Zhang 59a , R. Zhang 24 , X. Zhang 59b , Y. Zhang 15a,15d , Z. Zhang 131 , P. Zhao 48 , Y. Zhao 59b,131,ae , Z. Zhao 59a , A. Zhemchugov 78 , Z. Zheng 104 , D. Zhong 172 , B. Zhou 104 , C. Zhou 180 , L. Zhou 42 , M.S. Zhou 15a,15d , M. Zhou 154 , N. Zhou 59c , Y. Zhou 7 , C.G. Zhu 59b , H.L. Zhu 59a , H. Zhu 15a , J. Zhu 104 , Y. Zhu 59a , X. Zhuang 15a , K. Zhukov 109 , V. Zhulanov 121b,121a , A. Zibell 176 , D. Zieminska 64 , N.I. Zimine 78 , S. Zimmermann 51 , Z. Zinonos 114 , M. Zinser 98 , M. Ziolkowski 150 , G. Zobernig 180 , A. Zoccoli 23b,23a , K. Zoch 52 , T.G. Zorbas 148 , R. Zou 37 , M. Zur Nedden 19 , L. Zwalinski 36 1 Department of Physics, University of Adelaide, Adelaide, Australia 2 Physics Department, SUNY Albany, Albany, NY, United States of America 3 Department of Physics, University of Alberta, Edmonton, AB, Canada 4 (a) Department of Physics, Ankara University, Ankara; (b) Istanbul Aydin University, Istanbul; (c) Division of Physics, TOBB University of Economics and Technology, Ankara, Turkey 5 LAPP, Université Grenoble Alpes, Université Savoie Mont Blanc, CNRS/IN2P3, Annecy, France 6 High Energy Physics Division, Argonne National Laboratory, Argonne, IL, United States of America 7 Department of Physics, University of Arizona, Tucson, AZ, United States of America 8 Department of Physics, University of Texas at Arlington, Arlington, TX, United States of America 9 Physics Department, National and Kapodistrian University of Athens, Athens, Greece 10 Physics Department, National Technical University of Athens, Zografou, Greece 11 Department of Physics, University of Texas at Austin, Austin, TX, United States of America 12 (a) Bahcesehir University, Faculty of Engineering and Natural Sciences, Istanbul; (b) Istanbul Bilgi University, Faculty of Engineering and Natural Sciences, Istanbul; (c) Department of Physics, Bogazici University, Istanbul; (d) Department of Physics Engineering, Gaziantep University, Gaziantep, Turkey 13 Institute of Physics, Azerbaijan Academy of Sciences, Baku, Azerbaijan 14 Institut de Física d’Altes Energies (IFAE), Barcelona Institute of Science and Technology, Barcelona, Spain 15 (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 of Chinese Academy of Science (UCAS), Beijing, China 16 Institute of Physics, University of Belgrade, Belgrade, Serbia 17 Department for Physics and Technology, University of Bergen, Bergen, Norway 18 Physics Division, Lawrence Berkeley National Laboratory and University of California, Berkeley, CA, United States of America 19 Institut für Physik, Humboldt Universität zu Berlin, Berlin, Germany 20 Albert Einstein Center for Fundamental Physics and Laboratory for High Energy Physics, University of Bern, Bern, Switzerland 21 School of Physics and Astronomy, University of Birmingham, Birmingham, United Kingdom 22 Facultad de Ciencias y Centro de Investigaciónes, Universidad Antonio Nariño, Bogota, Colombia 23 (a) INFN Bologna and Universita’ di Bologna, Dipartimento di Fisica; (b) INFN Sezione di Bologna, Italy 24 Physikalisches Institut, Universität Bonn, Bonn, Germany 25 Department of Physics, Boston University, Boston, MA, United States of America 26 Department of Physics, Brandeis University, Waltham, MA, United States of America 27 (a) Transilvania University of Brasov, Brasov; (b) Horia Hulubei National Institute of Physics and Nuclear Engineering, Bucharest; (c) Department of Physics, Alexandru Ioan Cuza University of Iasi, Iasi; (d) National Institute 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 28 (a) Faculty of Mathematics, Physics and Informatics, Comenius University, Bratislava; (b) Department of Subnuclear Physics, Institute of Experimental Physics of the Slovak Academy of Sciences, Kosice, Slovak Republic 29 Physics Department, Brookhaven National Laboratory, Upton, NY, United States of America 30 Departamento de Física, Universidad de Buenos Aires, Buenos Aires, Argentina 31 California State University, CA, United States of America 32 Cavendish Laboratory, University of Cambridge, Cambridge, United Kingdom 33 (a) Department of Physics, University of Cape Town, Cape Town; (b) Department of Mechanical Engineering Science, University of Johannesburg, Johannesburg; (c) School of Physics, University of the Witwatersrand, Johannesburg, South Africa 34 Department of Physics, Carleton University, Ottawa, ON, Canada 35 (a) Faculté des Sciences Ain Chock, Réseau Universitaire de Physique des Hautes Energies – Université Hassan II, Casablanca; (b) Faculté des Sciences, Université Ibn-Tofail, Kénitra; (c) Faculté des Sciences Semlalia, Université Cadi Ayyad, LPHEA, Marrakech; (d) Faculté des Sciences, Université Mohamed Premier and LPTPM, Oujda; (e) Faculté des sciences, Université Mohammed V, Rabat, Morocco 36 CERN, Geneva, Switzerland 37 Enrico Fermi Institute, University of Chicago, Chicago, IL, United States of America 490 The ATLAS Collaboration / Physics Letters B 793 (2019) 469–492 38 LPC, Université Clermont Auvergne, CNRS/IN2P3, Clermont-Ferrand, France 39 Nevis Laboratory, Columbia University, Irvington, NY, United States of America 40 Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark 41 (a) Dipartimento di Fisica, Università della Calabria, Rende; (b) INFN Gruppo Collegato di Cosenza, Laboratori Nazionali di Frascati, Italy 42 Physics Department, Southern Methodist University, Dallas, TX, United States of America 43 Physics Department, University of Texas at Dallas, Richardson, TX, United States of America 44 (a) Department of Physics, Stockholm University; (b) Oskar Klein Centre, Stockholm, Sweden 45 Deutsches Elektronen-Synchrotron DESY, Hamburg and Zeuthen, Germany 46 Lehrstuhl für Experimentelle Physik IV, Technische Universität Dortmund, Dortmund, Germany 47 Institut für Kern- und Teilchenphysik, Technische Universität Dresden, Dresden, Germany 48 Department of Physics, Duke University, Durham, NC, United States of America 49 SUPA – School of Physics and Astronomy, University of Edinburgh, Edinburgh, United Kingdom 50 INFN e Laboratori Nazionali di Frascati, Frascati, Italy 51 Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany 52 II. Physikalisches Institut, Georg-August-Universität Göttingen, Göttingen, Germany 53 Département de Physique Nucléaire et Corpusculaire, Université de Genève, Genève, Switzerland 54 (a) Dipartimento di Fisica, Università di Genova, Genova; (b) INFN Sezione di Genova, Italy 55 II. Physikalisches Institut, Justus-Liebig-Universität Giessen, Giessen, Germany 56 SUPA – School of Physics and Astronomy, University of Glasgow, Glasgow, United Kingdom 57 LPSC, Université Grenoble Alpes, CNRS/IN2P3, Grenoble INP, Grenoble, France 58 Laboratory for Particle Physics and Cosmology, Harvard University, Cambridge, MA, United States of America 59 (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 Science and 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 60 (a) Kirchhoff-Institut für Physik, Ruprecht-Karls-Universität Heidelberg, Heidelberg; (b) Physikalisches Institut, Ruprecht-Karls-Universität Heidelberg, Heidelberg, Germany 61 Faculty of Applied Information Science, Hiroshima Institute of Technology, Hiroshima, Japan 62 (a) Department of Physics, Chinese University of Hong Kong, Shatin, N.T., Hong Kong; (b) Department of Physics, 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 63 Department of Physics, National Tsing Hua University, Hsinchu, Taiwan 64 Department of Physics, Indiana University, Bloomington, IN, United States of America 65 (a) INFN Gruppo Collegato di Udine, Sezione di Trieste, Udine; (b) ICTP, Trieste; (c) Dipartimento Politecnico di Ingegneria e Architettura, Università di Udine, Udine, Italy 66 (a) INFN Sezione di Lecce; (b) Dipartimento di Matematica e Fisica, Università del Salento, Lecce, Italy 67 (a) INFN Sezione di Milano; (b) Dipartimento di Fisica, Università di Milano, Milano, Italy 68 (a) INFN Sezione di Napoli; (b) Dipartimento di Fisica, Università di Napoli, Napoli, Italy 69 (a) INFN Sezione di Pavia; (b) Dipartimento di Fisica, Università di Pavia, Pavia, Italy 70 (a) INFN Sezione di Pisa; (b) Dipartimento di Fisica E. Fermi, Università di Pisa, Pisa, Italy 71 (a) INFN Sezione di Roma; (b) Dipartimento di Fisica, Sapienza Università di Roma, Roma, Italy 72 (a) INFN Sezione di Roma Tor Vergata; (b) Dipartimento di Fisica, Università di Roma Tor Vergata, Roma, Italy 73 (a) INFN Sezione di Roma Tre; (b) Dipartimento di Matematica e Fisica, Università Roma Tre, Roma, Italy 74 (a) INFN-TIFPA; (b) Università degli Studi di Trento, Trento, Italy 75 Institut für Astro- und Teilchenphysik, Leopold-Franzens-Universität, Innsbruck, Austria 76 University of Iowa, Iowa City, IA, United States of America 77 Department of Physics and Astronomy, Iowa State University, Ames, IA, United States of America 78 Joint Institute for Nuclear Research, Dubna, Russia 79 (a) Departamento de Engenharia Elétrica, Universidade Federal de Juiz de Fora (UFJF), Juiz de Fora; (b) Universidade Federal do Rio De Janeiro COPPE/EE/IF, Rio de Janeiro; (c) Universidade Federal de São João del Rei (UFSJ), São João del Rei; (d) Instituto de Física, Universidade de São Paulo, São Paulo, Brazil 80 KEK, High Energy Accelerator Research Organization, Tsukuba, Japan 81 Graduate School of Science, Kobe University, Kobe, Japan 82 (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 83 Institute of Nuclear Physics Polish Academy of Sciences, Krakow, Poland 84 Faculty of Science, Kyoto University, Kyoto, Japan 85 Kyoto University of Education, Kyoto, Japan 86 Research Center for Advanced Particle Physics and Department of Physics, Kyushu University, Fukuoka, Japan 87 Instituto de Física La Plata, Universidad Nacional de La Plata and CONICET, La Plata, Argentina 88 Physics Department, Lancaster University, Lancaster, United Kingdom 89 Oliver Lodge Laboratory, University of Liverpool, Liverpool, United Kingdom 90 Department of Experimental Particle Physics, Jožef Stefan Institute and Department of Physics, University of Ljubljana, Ljubljana, Slovenia 91 School of Physics and Astronomy, Queen Mary University of London, London, United Kingdom 92 Department of Physics, Royal Holloway University of London, Egham, United Kingdom 93 Department of Physics and Astronomy, University College London, London, United Kingdom 94 Louisiana Tech University, Ruston, LA, United States of America 95 Fysiska institutionen, Lunds universitet, Lund, Sweden 96 Centre de Calcul de l’Institut National de Physique Nucléaire et de Physique des Particules (IN2P3), Villeurbanne, France 97 Departamento de Física Teorica C-15 and CIAFF, Universidad Autónoma de Madrid, Madrid, Spain 98 Institut für Physik, Universität Mainz, Mainz, Germany 99 School of Physics and Astronomy, University of Manchester, Manchester, United Kingdom 100 CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille, France 101 Department of Physics, University of Massachusetts, Amherst, MA, United States of America 102 Department of Physics, McGill University, Montreal, QC, Canada 103 School of Physics, University of Melbourne, Victoria, Australia 104 Department of Physics, University of Michigan, Ann Arbor, MI, United States of America 105 Department of Physics and Astronomy, Michigan State University, East Lansing, MI, United States of America 106 B.I. Stepanov Institute of Physics, National Academy of Sciences of Belarus, Minsk, Belarus 107 Research Institute for Nuclear Problems of Byelorussian State University, Minsk, Belarus 108 Group of Particle Physics, University of Montreal, Montreal, QC, Canada 109 P.N. Lebedev Physical Institute of the Russian Academy of Sciences, Moscow, Russia 110 Institute for Theoretical and Experimental Physics of the National Research Centre Kurchatov Institute, Moscow, Russia 111 National Research Nuclear University MEPhI, Moscow, Russia The ATLAS Collaboration / Physics Letters B 793 (2019) 469–492 491 112 D.V. Skobeltsyn Institute of Nuclear Physics, M.V. Lomonosov Moscow State University, Moscow, Russia 113 Fakultät für Physik, Ludwig-Maximilians-Universität München, München, Germany 114 Max-Planck-Institut für Physik (Werner-Heisenberg-Institut), München, Germany 115 Nagasaki Institute of Applied Science, Nagasaki, Japan 116 Graduate School of Science and Kobayashi–Maskawa Institute, Nagoya University, Nagoya, Japan 117 Department of Physics and Astronomy, University of New Mexico, Albuquerque, NM, United States of America 118 Institute for Mathematics, Astrophysics and Particle Physics, Radboud University Nijmegen/Nikhef, Nijmegen, Netherlands 119 Nikhef National Institute for Subatomic Physics and University of Amsterdam, Amsterdam, Netherlands 120 Department of Physics, Northern Illinois University, DeKalb, IL, United States of America 121 (a) Budker Institute of Nuclear Physics and NSU, SB RAS, Novosibirsk; (b) Novosibirsk State University, Novosibirsk, Russia 122 Institute for High Energy Physics of the National Research Centre Kurchatov Institute, Protvino, Russia 123 Department of Physics, New York University, New York, NY, United States of America 124 Ochanomizu University, Otsuka, Bunkyo-ku, Tokyo, Japan 125 Ohio State University, Columbus, OH, United States of America 126 Faculty of Science, Okayama University, Okayama, Japan 127 Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, Norman, OK, United States of America 128 Department of Physics, Oklahoma State University, Stillwater, OK, United States of America 129 Palacký University, RCPTM, Joint Laboratory of Optics, Olomouc, Czech Republic 130 Center for High Energy Physics, University of Oregon, Eugene, OR, United States of America 131 LAL, Université Paris-Sud, CNRS/IN2P3, Université Paris-Saclay, Orsay, France 132 Graduate School of Science, Osaka University, Osaka, Japan 133 Department of Physics, University of Oslo, Oslo, Norway 134 Department of Physics, Oxford University, Oxford, United Kingdom 135 LPNHE, Sorbonne Université, Paris Diderot Sorbonne Paris Cité, CNRS/IN2P3, Paris, France 136 Department of Physics, University of Pennsylvania, Philadelphia, PA, United States of America 137 Konstantinov Nuclear Physics Institute of National Research Centre “Kurchatov Institute”, PNPI, St. Petersburg, Russia 138 Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA, United States of America 139 (a) Laboratório de Instrumentação e Física Experimental de Partículas – LIP; (b) Departamento de Física, Faculdade de Ciências, Universidade de Lisboa, Lisboa; (c) Departamento de Física, Universidade de Coimbra, Coimbra; (d) Centro de Física Nuclear da Universidade de Lisboa, Lisboa; (e) Departamento de Física, Universidade do Minho, Braga; (f ) Universidad de Granada, Granada (Spain); (g) Dep Física and CEFITEC of Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Caparica, Portugal 140 Institute of Physics of the Czech Academy of Sciences, Prague, Czech Republic 141 Czech Technical University in Prague, Prague, Czech Republic 142 Charles University, Faculty of Mathematics and Physics, Prague, Czech Republic 143 Particle Physics Department, Rutherford Appleton Laboratory, Didcot, United Kingdom 144 IRFU, CEA, Université Paris-Saclay, Gif-sur-Yvette, France 145 Santa Cruz Institute for Particle Physics, University of California Santa Cruz, Santa Cruz, CA, United States of America 146 (a) Departamento de Física, Pontificia Universidad Católica de Chile, Santiago; (b) Departamento de Física, Universidad Técnica Federico Santa María, Valparaíso, Chile 147 Department of Physics, University of Washington, Seattle, WA, United States of America 148 Department of Physics and Astronomy, University of Sheffield, Sheffield, United Kingdom 149 Department of Physics, Shinshu University, Nagano, Japan 150 Department Physik, Universität Siegen, Siegen, Germany 151 Department of Physics, Simon Fraser University, Burnaby, BC, Canada 152 SLAC National Accelerator Laboratory, Stanford, CA, United States of America 153 Physics Department, Royal Institute of Technology, Stockholm, Sweden 154 Departments of Physics and Astronomy, Stony Brook University, Stony Brook, NY, United States of America 155 Department of Physics and Astronomy, University of Sussex, Brighton, United Kingdom 156 School of Physics, University of Sydney, Sydney, Australia 157 Institute of Physics, Academia Sinica, Taipei, Taiwan 158 (a) E. Andronikashvili Institute of Physics, Iv. Javakhishvili Tbilisi State University, Tbilisi; (b) High Energy Physics Institute, Tbilisi State University, Tbilisi, Georgia 159 Department of Physics, Technion, Israel Institute of Technology, Haifa, Israel 160 Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Tel Aviv, Israel 161 Department of Physics, Aristotle University of Thessaloniki, Thessaloniki, Greece 162 International Center for Elementary Particle Physics and Department of Physics, University of Tokyo, Tokyo, Japan 163 Graduate School of Science and Technology, Tokyo Metropolitan University, Tokyo, Japan 164 Department of Physics, Tokyo Institute of Technology, Tokyo, Japan 165 Tomsk State University, Tomsk, Russia 166 Department of Physics, University of Toronto, Toronto, ON, Canada 167 (a) TRIUMF, Vancouver, BC; (b) Department of Physics and Astronomy, York University, Toronto, ON, Canada 168 Division of Physics and Tomonaga Center for the History of the Universe, Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Japan 169 Department of Physics and Astronomy, Tufts University, Medford, MA, United States of America 170 Department of Physics and Astronomy, University of California Irvine, Irvine, CA, United States of America 171 Department of Physics and Astronomy, University of Uppsala, Uppsala, Sweden 172 Department of Physics, University of Illinois, Urbana, IL, United States of America 173 Instituto de Física Corpuscular (IFIC), Centro Mixto Universidad de Valencia – CSIC, Valencia, Spain 174 Department of Physics, University of British Columbia, Vancouver, BC, Canada 175 Department of Physics and Astronomy, University of Victoria, Victoria, BC, Canada 176 Fakultät für Physik und Astronomie, Julius-Maximilians-Universität Würzburg, Würzburg, Germany 177 Department of Physics, University of Warwick, Coventry, United Kingdom 178 Waseda University, Tokyo, Japan 179 Department of Particle Physics, Weizmann Institute of Science, Rehovot, Israel 180 Department of Physics, University of Wisconsin, Madison, WI, United States of America 181 Fakultät für Mathematik und Naturwissenschaften, Fachgruppe Physik, Bergische Universität Wuppertal, Wuppertal, Germany 182 Department of Physics, Yale University, New Haven, CT, United States of America 183 Yerevan Physics Institute, Yerevan, Armenia a Also at Borough of Manhattan Community College, City University of New York, New York NY; United States of America. b Also at Centre for High Performance Computing, CSIR Campus, Rosebank, Cape Town; South Africa. c Also at CERN, Geneva; Switzerland. 492 The ATLAS Collaboration / Physics Letters B 793 (2019) 469–492 d Also at CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille; France. e Also at Département de Physique Nucléaire et Corpusculaire, Université de Genève, Genève; Switzerland. f Also at Departament de Fisica de la Universitat Autonoma de Barcelona, Barcelona; Spain. g Also at Department of Applied Physics and Astronomy, University of Sharjah, Sharjah; United Arab Emirates. h Also at Department of Financial and Management Engineering, University of the Aegean, Chios; Greece. i Also at Department of Physics and Astronomy, University of Louisville, Louisville, KY; United States of America. j Also at Department of Physics and Astronomy, University of Sheffield, Sheffield; United Kingdom. k Also at Department of Physics, California State University, East Bay; United States of America. l Also at Department of Physics, California State University, Fresno; United States of America. m Also at Department of Physics, California State University, Sacramento; United States of America. n Also at Department of Physics, King’s College London, London; United Kingdom. o Also at Department of Physics, St. Petersburg State Polytechnical University, St. Petersburg; Russia. p Also at Department of Physics, University of Fribourg, Fribourg; Switzerland. q Also at Department of Physics, University of Michigan, Ann Arbor MI; United States of America. r Also at Faculty of Physics, M.V. Lomonosov Moscow State University, Moscow; Russia. s Also at Giresun University, Faculty of Engineering, Giresun; Turkey. t Also at Graduate School of Science, Osaka University, Osaka; Japan. u Also at Hellenic Open University, Patras; Greece. v Also at Horia Hulubei National Institute of Physics and Nuclear Engineering, Bucharest; Romania. w Also at II. Physikalisches Institut, Georg-August-Universität Göttingen, Göttingen; Germany. x Also at Institucio Catalana de Recerca i Estudis Avancats, ICREA, Barcelona; Spain. y Also at Institute for Mathematics, Astrophysics and Particle Physics, Radboud University Nijmegen/Nikhef, Nijmegen; Netherlands. z Also at Institute for Particle and Nuclear Physics, Wigner Research Centre for Physics, Budapest; Hungary. aa Also at Institute of Particle Physics (IPP); Canada. ab Also at Institute of Physics, Academia Sinica, Taipei; Taiwan. ac Also at Institute of Physics, Azerbaijan Academy of Sciences, Baku; Azerbaijan. ad Also at Institute of Theoretical Physics, Ilia State University, Tbilisi; Georgia. ae Also at LAL, Université Paris-Sud, CNRS/IN2P3, Université Paris-Saclay, Orsay; France. af Also at Louisiana Tech University, Ruston LA; United States of America. ag Also at LPNHE, Sorbonne Université, Paris Diderot Sorbonne Paris Cité, CNRS/IN2P3, Paris; France. ah Also at Manhattan College, New York NY; United States of America. ai Also at Moscow Institute of Physics and Technology State University, Dolgoprudny; Russia. aj Also at National Research Nuclear University MEPhI, Moscow; Russia. ak Also at Physics Department, An-Najah National University, Nablus; Palestine. al Also at Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, Freiburg; Germany. am Also at School of Physics, Sun Yat-sen University, Guangzhou; China. an Also at The City College of New York, New York NY; United States of America. ao Also at The Collaborative Innovation Center of Quantum Matter (CICQM), Beijing; China. ap Also at Tomsk State University, Tomsk, and Moscow Institute of Physics and Technology State University, Dolgoprudny; Russia. aq Also at TRIUMF, Vancouver BC; Canada. ar Also at Universidad de Granada, Granada (Spain); Spain. as Also at Universita di Napoli Parthenope, Napoli; Italy. ∗ Deceased.