Physics Letters B 798 (2019) 134949 Contents lists available at ScienceDirect Physics Letters B www.elsevier.com/locate/physletb Measurement of the production cross section for a Higgs boson in association with√a vector boson in the H → W W ∗ → ν ν channel in pp collisions at s = 13 TeV with the ATLAS detector .ATLAS Collaboration  a r t i c l e i n f o a b s t r a c t Article history: A measurement of the Higgs boson production cross sections via associated W H and Z H production Received 26 March 2019 using H → W W ∗ → ν ν decays, where  stands for either an electron or a muon, is presented. Results Received in revised form 28 August 2019 for combined W H and Z H production are also presented. The analysis uses events produced in proton– Accepted 16 September 2019 proton collisions collected with the ATLAS detector at the Large Hadron Collider in 2015 and 2016. The Available online 23 September 2019 Editor: M. Doser data correspond to an integrated luminosity of 36.1 fb−1 recorded at a centre-of-mass energy of 13 TeV. The products of the H → W W ∗ branching fraction times the W H and Z H cross sections are measured to be 0.67+ 0.31 +0.18 +0.31 +0.15 −0.27 (stat.)−0.14 (syst.) pb and 0.54−0.24 (stat.)−0.07 (syst.) pb respectively, in agreement with the Standard Model predictions. © 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 H → τ τ are considered as background. The leading-order Feynman diagrams for the W H and Z H production processes are depicted Higgs boson production in association with a W or Z boson, in Fig. 1. which is respectively denoted by W H and Z H , and collectively re- In the W H channel, multivariate discriminants are used to ferred to as V H associated production in the following, provides maximise the sensitivity to the Higgs boson signal, while in the direct access to the Higgs boson couplings to weak bosons. In par- Z H channel the analysis is performed through selection require- ticular, in the W H mode with subsequent H → W W ∗ decay, the ments. The distribution of these W H discriminants, together with Higgs boson couples only to W bosons, at both the production and event counts in background control regions and the signal regions decay vertices. in the Z H channel, are combined in a binned maximum-likelihood This paper presents a measurement of the corresponding pro- fit to extract the signal yield and the background normalisations. duction cross sections through the decay H → W W ∗ → ν ν , The maximum-likelihood fit provides results for the W H and the using √ proton–proton collisions at a centre-of-mass energy of Z H channels separately and for their combination V H , assuming s = 13 TeV. The data correspond to an integrated luminosity the Standard Model (SM) prediction for the relative cross sections of 36.1 fb−1 and were recorded by the ATLAS detector √ at the of the two production processes. Large Hadron Collider (LHC). Previous measurements at s = 8 TeV were performed √ by the ATLAS [1] and−CMS [2] Collaborations and 2. ATLAS detector 1 recently at s = 13 TeV with 35 √.9 fb of data by the CMS Col- laboration [3]. Recent results at s = 13 TeV on V H production in The ATLAS experiment [10–12] is a multi-purpose particle de- other decay modes can be found in Refs. [4–9]. tector with a forward–backward symmetric cylindrical geometry The analysis is performed using events with three (3) or four and a near 4π coverage in solid angle.1 It consists of an in- (4) charged leptons (electrons or muons) in the final state, target- ing the W H and Z H channels respectively. Leptonic decays of τ leptons, from H → W W ∗ → τ ντ ν or H → W W ∗ → τ ν ν or from 1 ATLAS uses a right-handed coordinate system with its origin at the nominal the associated vector bosons, are considered as signal, while no interaction point (IP) in the centre of the detector and the z-axis along the beam specific selection is performed for events with hadronically decay- pipe. The x-axis points from the IP to the centre of the LHC ring, and the y-axis points upwards. Cylindrical coordinates (r , φ) are used in the transverse plane, φ ing τ leptons in the final state. Events from V H production with being the azimuthal angle around the z-axis. The pseudorapidity is defined in terms  angle θ as η = − ln tan(θ/2). Angular distance is measured in units of the polar of R ≡ ( η)2 + ( φ)2 . Transverse momentum and energy are defined as p T =  E-mail address: atlas.publications@cern.ch. p sin θ and E T = E sin θ respectively. https://doi.org/10.1016/j.physletb.2019.134949 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 . 2 ATLAS Collaboration / Physics Letters B 798 (2019) 134949 Fig. 1. Tree-level Feynman diagrams for the V H ( H → W W ∗ ) topologies considered in this paper: (a) 3 channel and (b) 4 channel. Table 1 Monte Carlo generators used to model the signal and background processes. Alternative generators, underlying event and parton-showering models, used to estimate systematic uncertainties, are shown in parentheses. In the last column the prediction order for the total cross section is shown. “Pythia6” refers to version 6.428, “Pythia8” refers to versions 8.210 or 8.186. Process Generator UEPS model Prediction order (alternative) (alternative) for total cross section qq̄ → W H Powheg-Box v2 MiNLO Pythia8 NNLO QCD + NLO EW [16–18] (Herwig 7) qq̄ → Z H Powheg-Box v2 MiNLO Pythia8 NNLO QCD + NLO EW [16–18] (Herwig 7) gg → Z H Powheg-Box v2 Pythia8 NLO + NLL [19] (Herwig 7) ggF H Powheg-Box v2 NNLOPS Pythia8 NNNLO QCD + NLO EW [20] VBF H Powheg-Box v2 Pythia8 NNLO QCD + NLO EW [21] t t̄ Powheg-Box v2 Pythia8 NNLO+NNLL [22] (Herwig 7) (Sherpa 2.2.1) (Sherpa 2.2.1) Wt Powheg-Box v1 Pythia6 NLO [23] t t̄ W / Z MG5_aMC@LO Pythia8 NLO [24,25] tZ MG5_aMC@LO Pythia6 LO [26] qq̄/qg → ν  Sherpa 2.2.2 Sherpa 2.2.2 NLO [27] (Powheg-Box v2) (Herwig++) qq̄/qg →  Sherpa 2.1/2.2.2 Sherpa 2.1/2.2.2 NLO [27] (Powheg-Box v2) (Herwig++) gg →  Sherpa 2.1.1 Sherpa 2.1.1 NLO [28] VVV Sherpa 2.2.2 Sherpa 2.2.2 NLO [29] (MG5_aMC@NLO) (Pythia8) ner tracking detector (ID) surrounded by a thin superconducting arate programs were used to generate the hard scattering pro- solenoid providing a 2 T axial magnetic field, electromagnetic (EM) cess and to model the underlying event and the parton shower- and hadronic calorimeters, and a muon spectrometer (MS). The in- ing (UEPS). A description of the MC samples is given in Table 1. ner tracking detector covers the pseudorapidity range |η| < 2.5. It They are normalised to cross-section predictions calculated with consists of silicon pixel, silicon micro-strip, and transition-radiation the QCD and electroweak (EW) orders specified in the last column tracking detectors. Lead/liquid-argon (LAr) sampling calorimeters of Table 1. provide electromagnetic energy measurements with high granular- The qq̄ → W H and qq̄ → Z H processes were generated with ity. A hadronic (steel/scintillator-tile) calorimeter covers the central Powheg-Box v2 [30] MiNLO interfaced to Pythia8 [31], with the pseudorapidity range (|η| < 1.7). The endcap and forward regions AZNLO set of tuned parameters (tune) [32] for underlying event, are instrumented with LAr calorimeters for both EM and hadronic showering and hadronisation. The g g → Z H process was simu- energy measurements up to |η| = 4.9. The muon spectrometer lated with Powheg-Box v2 + Pythia8 with the AZNLO tune for surrounds the calorimeters and is based on three large air-core underlying event, showering and hadronisation. For the V H sam- toroidal superconducting magnet systems that provide a field in- ples, the PDF4LHC15 parton distribution function (PDF) set [33] tegral between 2.0 and 6.0 T m across most of the detector. The was used for the hard scattering process in Powheg-Box v2 and muon spectrometer includes a system of precision tracking cham- the CTEQ6L1 PDF set [34] was used for the parton showering in bers covering the region |η| < 2.7 and fast detectors for triggering Pythia8. Herwig 7 [35], with the MMHT2014lo68cl PDF set [36], within the range |η| < 2.4. A two-level trigger system is used to was used as an alternative parton-showering model for V H . The select events [13]. uncertainty due to the PDF choice is smaller than the uncertainty obtained by using Herwig as an alternative parton shower model 3. Signal and background Monte Carlo simulation (Section 7). The gluon–gluon fusion (ggF) events were generated with Monte Carlo (MC) event generators are used to model signal Powheg-Box v2 NNLOPS [37] interfaced to Pythia8 with the and background processes. All signal samples were generated with AZNLO tune. The vector-boson fusion (VBF) events were gener- a Higgs boson mass of 125 GeV [14,15]. For most processes, sep- ated with Powheg-Box v2, interfaced to Pythia8. For the ggF and ATLAS Collaboration / Physics Letters B 798 (2019) 134949 3 VBF samples, the PDF4LHC15 PDF set was used for the hard scat- are required to satisfy |η| < 2.47, excluding 1.37 < |η| < 1.52, tering process in Powheg-Box v2 and the CTEQ6L1 PDF set was which corresponds to the transition region between the barrel and used for the parton showering in Pythia8. The contribution from the endcap EM calorimeters. The efficiency for electron identifi- the t t̄ H and t H production modes is negligible. cation ranges from 88% to 94%, depending on electron p T and η . The top-quark pair production (t t̄) was simulated with Powheg- Muons are reconstructed by combining ID and MS tracks with con- Box v2 [38] using the NNPDF 3.0 NNLO PDF set [39] and inter- sistent trajectories and curvatures. An overall fit of hits from the faced to Pythia8 using the NNPDF 2.3 PDF set [40] for parton ID track, energy loss in the calorimeter and the hits of the track in showering, with the A14 tune [41]. For t t̄ production, Sherpa [42] the muon system is used to form muon candidates, as described in 2.2.1, with the NNPDF 3.0 PDF set, was used as an alternative Ref. [55]. The efficiency for muon identification is close to 95% over generator while Herwig 7, with the MMHT2014lo68cl PDF set, the full instrumented η range. To suppress particles misidentified was used as an alternative UEPS model. The single-top-quark as leptons, several identification requirements as well as impact production W t was generated with Powheg-Box v1 [23] inter- parameter, calorimeter and track isolation criteria [54,55] are ap- faced to Pythia6 [43] for parton showering with the Perugia2012 plied. tune [44]. EvtGen 1.2.0 [45] was used for the simulation of b-quark Jets are reconstructed using the anti-kt algorithm with radius and c-quark decays. The t t̄ W / Z and t Z processes were gener- parameter R = 0.4 [56,57]. The four-momenta of jets are corrected ated at leading order (LO) with MG5_aMC@LO [25] version 2.2.2 for the effects of calorimeter non-compensation, energy loss in (t t̄ W / Z ) and 2.2.1 (t Z ) interfaced to Pythia8 (t t̄ W / Z ) and Pythia6 non-instrumented regions, and contributions from pile-up [58]. (t Z ), using the NNPDF2.3 LO PDF set. Jets are required to have |η| < 4.5, with p T > 25 GeV for the region The qq̄/qg → V V ∗ samples with final states ν  and  [46] |η| < 2.5 and p T > 30 GeV for the region 2.5 < |η| < 4.5. A multi- were generated with Sherpa 2.2.2, with the exception of the Z Z ∗ variate selection [59] is used to suppress jets with p T < 60 GeV sample in the W H analysis for which Sherpa 2.1 was used; the and |η| < 2.4 originated from pile-up. Furthermore, to suppress CT10 PDF set [47] and the NNPDF 3.0 PDF set were used for ver- pile-up jets in the forward region, jet shapes and topological jet sions 2.1 and 2.2.2, respectively. Powheg-Box v2 [48] was used correlations in pile-up interactions are exploited [60]. Jets with p T as an alternative generator for V V ∗ , with Herwig++, using the > 20 GeV and |η| < 2.5 containing b-hadrons (b-jets) are identified CTEQ6L1 PDF set, for parton showering. Among the loop-induced using a multivariate technique [61] with an efficiency of 85%, esti- g g-initiated diboson processes, the only relevant process in this mated from simulated t t̄ events. The multivariate technique gives analysis is g g → Z Z ∗ , for which a K -factor of 1.55 was used [28]. rejection factors against jets originating from a light quark or gluon This process was simulated with Sherpa 2.1.1, using the CT10 PDF and jets containing c-hadrons of 33 and 3, respectively. set. The missing transverse momentum p  Tmiss with magnitude E Tmiss The triboson V V V samples were generated with Sherpa 2.2.2 in each event is calculated from the negative vectorial sum of the and the NNPDF 3.0 PDF set. MG5_aMC@NLO was used as an alter- transverse momenta of electrons, muons, and jets. It uses both native generator for V V V , with Pythia8, using the NNPDF2.3 LO track-based and calorimeter-based measurements [62]. PDF set. The same PDF sets were used for the hard scattering and the parton showering in all the Sherpa samples described above. 5. Event selection All simulated samples include the effect of pile-up from mul- tiple interactions in the same and neighbouring bunch crossings. In the W H channel, exactly three isolated leptons with p T > This was achieved by overlaying minimum-bias events, simulated 15 GeV are required with a total charge of ±1. The lepton with using Pythia8 with the A2 tune [49] and MSTW2008LO PDF unique charge is labelled 0 , the lepton closest to 0 in angular set [50]. All samples were processed through the Geant 4 [51] AT- distance R is labelled 1 , and the remaining lepton is labelled LAS detector simulation [52]. 2 . In signal events leptons 0 and 1 are most likely to originate from the H → W W ∗ decay, with probabilities of 99% and 85% re- 4. Event reconstruction spectively. The most prominent background processes to the W H chan- Candidate signal events are selected using triggers that require nel are W Z / W γ ∗ production and top-quark processes with either a single isolated lepton with minimum transverse momentum (p T ) three prompt leptons, e.g. t t̄ V , or two prompt leptons and one thresholds between 24 GeV and 26 GeV for electrons and between non-prompt lepton from a b-hadron decay, e.g. t t̄. Other important 20 GeV and 26 GeV for muons, depending on the data-taking pe- background processes are Z Z ∗ (including Z γ ∗ ), Z γ and Z +jets riod. At least one of the leptons reconstructed offline is required production; they may satisfy the signal selection requirements if to have triggered the event and to have a p T higher than the a lepton is undetected, in the case of Z Z ∗ , or if they contain a nominal trigger threshold by at least 1 GeV. The single-lepton misidentified or non-prompt lepton, in the case of Z γ and Z +jets trigger efficiencies on the plateau are approximately 70% for sin- production. Processes with three prompt leptons in the final state gle muons with |η| < 1.05, 90% for single muons in the range such as tribosons, in particular W W W , also contribute to the 1.05 < |η| < 2.40 and greater than 90% for single electrons in the background. Contributions from background processes that include range |η| < 2.47. The trigger efficiency for the signal events, esti- more than one misidentified lepton, such as W +jets production mated after the preselection, is 94% for W H and 98.5% for Z H . and inclusive bb̄ pair production, are negligible. The background Selected events are required to have at least one primary vertex from top-quark production is suppressed by vetoing events if they reconstructed from at least two associated tracks, each with trans- contain any b-tagged jet. verse momentum p T > 400 MeV, as described in Ref. [53]. If an The analysis of the W H channel separates events with at least event has more than one reconstructed primary vertex, the vertex one same-flavour opposite-sign charge (SFOS) lepton pair from with the largest track p 2T is selected for the analysis. events with zero SFOS lepton pairs, which have different signal- Electrons are reconstructed from clusters of energy deposits in to-background ratios. Due to the presence of Z →  decays as the EM calorimeter matched to ID tracks, and are identified using a dominant background, the former is hereafter referred to as criteria based on the calorimeter shower shape, the quality of the the Z -dominated category, while the latter is referred to as the match between the track and the cluster and the amount of transi- Z -depleted category. In the Z -dominated category, the major back- tion radiation emitted in the ID, as described in Ref. [54]. Electrons ground processes are those involving Z bosons. Events are ve- 4 ATLAS Collaboration / Physics Letters B 798 (2019) 134949 Fig. 2. Distribution of (a) angular separation R 0 1 and (b) BDTZdom distribution in the Z -dominated category. The dashed line shows the W H signal scaled by a factor of 30. The hatched band in the upper panel and the shaded band in the lower panel show the total statistical and experimental systematic uncertainty in background predictions. The W Z / W γ ∗ and top-quark background processes are normalised with the normalisation factors from the control region analysis (Table 4). The Z +jets and Z γ background processes are estimated with the data-driven technique described in Section 6. toed if they contain more than one jet. This requirement further tio in these bins is about 0.05, 0.09 and 0.19, respectively. The full suppresses top-quark events with an additional non-prompt lep- Z -dominated event selection is summarised in Table 2. ton from b-hadron decays. In order to select final states with In the Z -depleted category, the two major background pro- neutrinos, E Tmiss is required to be above 30 GeV. The invariant cesses are W Z / W γ ∗ with Z /γ ∗ → τ τ̄ and t t̄, where W Z / W γ ∗ masses m of all SFOS pairs are required to satisfy a Z -veto se- has the same signature of the signal, namely three prompt lep- lection: |m − m Z | > 25 GeV. The last two requirements suppress tons, while t t̄ contains a misidentified or non-prompt lepton from W Z / W γ ∗ and Z Z ∗ events, and improve the Z +jets rejection. In a jet. Two separate BDTs, named BDT W Z and BDTtt̄ , are trained order to suppress background events from heavy-flavour quarko- to allow an optimal background rejection. The BDT W Z uses 11 in- nia, the smallest invariant mass of SFOS pairs is required to be put variables, of which three common to the BDTZdom are m0 1 , greater than 12 GeV. The signal efficiency of this selection with E Tmiss and η1 2 ; the other variables are the transverse momenta    respect to the preselection is 34.6%. A discriminant based on a of the three leptons (p T0 , p T1 , p T2 ), the transverse mass (mT 1 ) 0 boosted decision tree (BDT) [63,64] is used to achieve a further built from 0 , 1 and p  Tmiss , the invariant mass of the electrons separation between signal and background processes. The main with same-sign charge (mee ), the transverse impact parameter sig- purpose of the multivariate classifier, named BDTZdom , is to distin- nificances of the lepton with lowest p T (|d0,sig,min |), the transverse guish between signal and the dominant W Z / W γ ∗ and Z Z ∗ back- impact parameter significances of the lepton with second-lowest ground processes, and hence it is trained against these two back- p T and opposite charge with respect to the lepton with lowest p T ground processes. The BDTZdom uses seven input variables. They (|d0,sig,mid |) and the compatibility of the event with the W Z hy- are the magnitude of the vectorial sum of lepton transverse mo- pothesis F α .2  menta (| p Ti |), the invariant masses of the first lepton pair (m0 1 ) A definition of the most likely lepton from heavy-flavour de- and of the three leptons (m ), the angular distance R 0 1 , E Tmiss cays (HFL ) is crucial for an optimal performance of the BDTtt̄ . For and the pseudorapidity separation between the leptons with the this purpose, a BDTHFL is trained purely on data using track and same charge ( η1 2 ). Moreover the BDT uses the transverse mass calorimeter isolation as well as impact-parameter variables as in-      put. The lepton with the minimal BDTHFL output is selected as HFL . of the W boson, mTW = 2 p TW · E Tmiss · 1 − cos φ W , p Tmiss , The BDTtt̄ uses nine input variables, of which two common to the built from the p  Tmiss and the lepton W which is the lepton not be- BDTZdom and BDT W Z are m0 1 and η1 2 , one common to the longing to the SFOS lepton pair with invariant mass closer to the Z BDTZdom is R 0 1 , and the other input variables are the number j boson mass, and could be either 1 or 2 . Fig. 2 shows the distribu- of jets (N jet ), the transverse momentum of the leading jet (p Tlead ), tion of R 0 1 , which is the most powerful variable in the BDTZdom the invariant mass of the leptons with same-sign charge (m1 2 ), training, and the BDTZdom distribution in the Z -dominated cate- and three HFL -related variables: its BDTHFL output, its transverse  gory, before applying any selection requirement on the BDTZdom momentum, p THFL , and the invariant mass built from it together score. The Z -dominated signal region (SR), defined as the events with high-ranking BDTZdom score (BDTZdom > 0.3), is divided into 2 Given the reconstructed charged-lepton momenta and the p  Tmiss , the event kine- three bins with increasing sensitivity: 0.3 ≤ BDTZdom < 0.5, 0.5 ≤ matics can be calculated under the W Z with Z → τ τ hypothesis and using the collinear approximation for the τ decays with one remaining unknown, e.g. the ra- BDTZdom < 0.7 and 0.7 ≤ BDTZdom < 1.0. This binning is the result tio of one τ energy to the energy of the lepton from this τ decay. This unknown is of an optimisation to find the minimal number of BDT bins that varied and the number of physical kinematic solutions is taken as a measure of the gives the highest sensitivity. The expected signal-to-background ra- compatibility with the W Z hypothesis. ATLAS Collaboration / Physics Letters B 798 (2019) 134949 5 Table 2 Event selection criteria used to define the signal regions in the W H and Z H analyses. The symbols are defined in the text. WH ZH Preselection 3 isolated leptons (p T > 15 GeV) 4 isolated leptons (p T > 10 GeV) total lepton charge ±1 total lepton charge 0 Category Z -dominated Z -depleted 2-SFOS 1-SFOS Number of SFOS 2 or 1 0 2 1 Number of jets ≤1 — ≤1 ≤2 Number of b-jets 0 0 0 0 E Tmiss [GeV] > 30 — > 45 — p 4T [GeV] — — > 45 — m [GeV] > 12 (min. SFOS) — > 10 > 10 |m − m Z | [GeV] > 25 (SFOS) — < 10 (m2 3 ) < 10 (m2 3 ) m0 1 [GeV] — — < 55 < 60 φboost 0 1 — — < 2.3 < 1.9 mτ τ [GeV] — — — < 50 φ0 1 , p miss [rad] — — — > 0.4 T m4 [GeV] — — > 140 — BDT BDTZdom > 0.3 BDTtt̄ > 0.2&BDT W Z > 0.15 — — Fig. 3. Distribution of (a) BDT W Z and (b) BDTtt̄ in the Z -depleted category. The dashed line shows the W H signal scaled by a factor of 10. The hatched band in the upper panel and the shaded band in the lower panel show the total statistical and experimental systematic uncertainty in background predictions. The W Z / W γ ∗ and top-quark background processes are normalised with the normalisation factors from the control region analysis (Table 4). Table 3 Summary of the Z -depleted fit regions. Bin 1 Bin 2 Bin 3 Bin 4 Bin 5 Bin 6 0.2 ≤ BDTtt̄ < 0.3 0.3 ≤ BDTtt̄ < 0.45 0.45 ≤ BDTtt̄ 0.15 ≤ BDT W Z < 0.35 0.35 ≤ BDT W Z 0.15 ≤ BDT W Z < 0.35 0.35 ≤ BDT W Z 0.15 ≤ BDT W Z < 0.35 0.35 ≤ BDT W Z with the closest opposite-charge lepton (mHFL cloc ). Fig. 3 shows two bins in BDT W Z as shown in Table 3. The expected signal- the outputs of BDT W Z and BDTtt̄ in the Z -depleted category, be- to-background ratio in these bins ranges from about 0.07 in the fore applying any selection requirements on the BDT scores. first bin up to about 3.6 in the last bin. The signal efficiency with The choice of input variables for the different BDTs was the respect to the preselection, before any cut on the BDT scores, is result of an optimisation study where several thousand different 23.5%. BDTs using different set of input variables have been compared and The Z H channel requires events to contain four isolated lep- the best performing BDTs have been selected for the final analysis. tons with p T > 10 GeV and total electric charge of zero. Events The full Z -depleted event selection is summarised in Table 2. that contain a SFOS lepton pair with m < 10 GeV are rejected to The events with high-ranking BDT scores (BDTtt̄ > 0.2 and BDT W Z suppress the contamination from heavy-flavour quarkonia. Follow- > 0.15) are used to define the Z -depleted SR. In this region, the ing this preselection, events are classified according to the number BDT scores are used as discriminant variables in the statistical of SFOS lepton pairs: 1-SFOS and 2-SFOS. Events with no SFOS lep- analysis, with three bins in BDTtt̄ , each being subdivided into ton pairs are not considered. 6 ATLAS Collaboration / Physics Letters B 798 (2019) 134949 Fig. 4. Distributions of (a) the azimuthal separation between the Higgs-candidate lepton pair and the missing transverse momentum φ0 1 , p miss in 1-SFOS events and (b) T the missing transverse momentum E Tmiss in 2-SFOS events, after preselection. For the latter the last bin contains overflow events. The dashed line shows the Z H signal scaled by a factor 20 (left) and by a factor 250 (right). The hatched band in the upper panel and the shaded band in the lower panel show the total statistical and experimental systematic uncertainty in background predictions. The Z Z ∗ background process is normalised in the 2-SFOS case with the normalisation factor from the control region analysis (Table 4). The Mis-Id background is estimated with the data-driven technique described in Section 6. The reconstruction of the Z H process proceeds through the contribution which becomes the dominant background source af- identification of the leptons from the Z boson, called 2 and 3 , ter the b-tagged jet veto and m0 1 selection are applied. Fig. 4(b) as the SFOS lepton pair with invariant mass closest to the Z bo- shows the E Tmiss distribution for 2-SFOS events after the prese- son mass, m Z . Then, the remaining two leptons, labelled 0 and lection. In order to be orthogonal to the H → Z Z ∗ analysis of 1 , are candidates for originating from the Higgs boson decay. The Ref. [66], 2-SFOS events are required to have an invariant mass background in the Z H channel is almost exclusively due to Z Z ∗ of the four-lepton system, m4 , above 140 GeV. The full event se- production. This constitutes ∼92% of the total background after the lection for Z H is summarised in Table 2. preselection is applied. Processes with four prompt leptons in the The total efficiency times acceptance of this selection for the final state such as triboson production, in particular Z W W , which process W H with subsequent H → W W ∗ decay is about 0.073% has the same signature as the signal, and t t̄ Z also contribute to while for Z H it is about 0.026%. These numbers are given with the background. Other background processes such as W Z / W γ ∗ , respect to all W and Z decays. Z +jets and t V may contribute when at least one jet, hadron or a converted photon is misidentified as a lepton. 6. Background estimation In order to suppress the t t̄ Z process, events containing b-tagged jets are rejected and at most one and two jets are allowed in The main background contamination originates from processes 2-SFOS and 1-SFOS classes, respectively. To reduce the Z Z ∗ back- with the same final state as the signal, namely diboson production ground process in events with two SFOS lepton pairs, a threshold (W Z / W γ ∗ , Z Z ∗ ), top-quark processes with three or four prompt of 45 GeV is applied to the E Tmiss and to the vector sum of the leptons such as t t̄ V , and triboson production. Other relevant back- ground contributions arise from processes, such as t t̄ or Z +jets, lepton transverse momenta, p 4T . The invariant mass of 2 and where the reconstructed leptons either originate from non-prompt 3 , m2 3 , is required to satisfy |m2 3 − m Z | < 10 GeV, and the decays of heavy-flavour hadrons or from jets misidentified as lep- invariant mass of 0 and 1 , m0 1 , is required to be between tons. 10 GeV and 60 GeV (55 GeV) in 1-SFOS (2-SFOS) events. The vari- Two dedicated regions, hereafter named control regions (CRs), able φboost denotes the difference in azimuthal angle between 0 1 are used to estimate the normalisation factors (NFs) of the main the leptons from the Higgs boson candidate in the frame where prompt background processes by fitting the expected yields from the Higgs boson p T is zero. The Higgs boson transverse momen-  simulation to data: W Z / W γ ∗ for the W H channel and Z Z ∗ for tum is approximated with p  TH ≈ −p TZ , or p TH ≈ −p TZ − p jetT if at the Z H channel in the 2-SFOS SR. In the 1-SFOS SR, Z Z ∗ is esti- least one jet is present in the event. Events are required to satisfy mated purely from simulation. φboost 0 1 < 1.9 (2.3) rad in the 1-SFOS (2-SFOS) class. In 1-SFOS The CRs are made orthogonal to the corresponding SRs by in- events the Z Z ∗ process contributes through the Z → τ τ decay, verting various selection criteria with respect to the SR definitions. therefore the reconstructed mass of the τ pair, mτ τ is required to The W Z CR is defined by reversing the Z -veto in the Z -dominated be below 50 GeV; mτ τ is computed using the collinear approxima- W H signal region. To improve the purity of the W Z CR, the min- tion method [65]. In addition, the azimuthal separation between imum E Tmiss is increased from 30 GeV to 50 GeV. The Z Z CR is the Higgs-candidate lepton pair and the p  Tmiss , φ  , p miss , is re- defined by inverting the m0 1 requirement defined in the Z H 0 1 T quired to be above 0.4 rad. The final selection of these variables is 2-SFOS SR. In order to increase the number of events, the E Tmiss , optimised in order to maximise the signal significance. Fig. 4(a) il- φboost , p 4T , and m4 requirements are removed. Table 4 sum- 0 1 lustrates the discriminating power of the φ  , p miss variable for marises the event selection for the W Z and Z Z CRs and the NFs 0 1 T 1-SFOS events after the preselection. This variable reduces the ZZ* for the background processes, obtained from the fit described in ATLAS Collaboration / Physics Letters B 798 (2019) 134949 7 Fig. 5. Post-fit distributions of the dilepton invariant mass m0 1 in the W Z CR (a) and of the four-lepton invariant mass m4 in the Z Z CR (b). For the latter the last bin contains overflow events. Post-fit distributions of the dilepton invariant mass m0 1 is shown also in the top-quark CR (c). The hatched band in the upper panel and the shaded band in the lower panel show the total statistical and experimental systematic uncertainty in background predictions. The Mis-Id background is estimated with the data-driven technique described in Section 6. Section 8. The NFs are hereby completely dominated by the CR Table 4 Definition of control regions in the W H and Z H analyses. Selections indicated in statistics and their values do not change when only the control re- boldface font are designed to ensure the control region (CR) is orthogonal to the gions are used in the fit. Figs. 5(a) and 5(b) show the distributions relevant SR. In the last line normalisation factors which scale the corresponding of m0 1 in the W Z CR and the invariant mass of the four lep- yields in the signal region are shown with their uncertainties, including both the tons in the Z Z CR, as obtained from the final fit in the statistical statistic and the systematic uncertainties. analysis (post-fit) described in Section 8. Channel (Category) W H (Z -dominated and Z -depleted) Z H (2-SFOS) The background contributions with misidentified leptons are es- CR WZ Top-quark ZZ timated using different techniques. The top-quark background in Number of leptons 3 3 4 the W H channels is normalised using a CR (top-quark CR) defined Total lepton charge ±1 ±1 0 by requiring at least one b-tagged jet. To improve the purity of Number of SFOS 2 or 1 ≤2 2 the top-quark CR, the minimum E Tmiss is increased from 30 GeV to Number of jets ≤1 ≥1 ≤1 Number of b-jets 0 ≥1 0 50 GeV if at least one SFOS pair is present in the event. Processes E Tmiss [GeV] > 50 > 50 (2 or 1 SFOS) — with one misidentified lepton (t t̄ and W t) constitute 94% of the |m − m Z | [GeV] < 25 > 25 (2 or 1 SFOS) < 10 (m2 3 ) top-quark CR, the remaining events contain three prompt leptons m0 1 [GeV] — — > 55 from t t̄ W decays. The full selection requirements applied to define m (min. SFOS) [GeV] > 12 > 12 (2 or 1 SFOS) — the top-quark CR and the measured NF are also summarised in Ta- Normalisation factors 0.99±0.05 0.97±0.08 1.13±0.06 ble 4. Fig. 5(c) shows the m0 1 distribution in the top-quark CR as obtained from the final fit. 8 ATLAS Collaboration / Physics Letters B 798 (2019) 134949 Table 5 Post-fit predictions and data yields in the four SRs. The uncertainties include those from the sample statistics, and the theoretical and experimental systematic uncertain- ties. The sum of the single contributions may differ from the total value due to rounding. Moreover, the total uncertainty differs from the sum in quadrature of the single-process uncertainties due to the correlations. “Other Higgs” contains Higgs production mecha- nisms and decay processes different from V H and H → W W ∗ respectively, except for the H → Z Z ∗ contribution which is included in the “ Z Z ∗ ” row. The corresponding pre- fit predictions for the background processes differ only by the normalization factors listed in Table 4. Process WH ZH Z -dominated Z -depleted 1-SFOS 2-SFOS WH 11 ± 6 5.8 ± 2.8 — ZH 1.1 ± 0.6 0.61 ± 0.34 3.3 ± 1.7 1.8 ± 0.9 W Z /W γ ∗ 40.1 ± 2.8 1.7 ± 0.5 — Z Z∗ 2.4 ± 1.1 0.27 ± 0.09 0.14 ± 0.14 1.2 ± 0.3 VVV 1.5 ± 0.1 0.71 ± 0.11 0.32 ± 0.05 0.20 ± 0.03 t V /t t̄ V 0.14 ± 0.03 0.13 ± 0.03 0.04 ± 0.02 0.03 ± 0.01 Other top-quark 8.4 ± 2.6 1.9 ± 0.8 — Other Higgs 0.31 ± 0.03 0.06 ± 0.01 <0.01 0.04 ± 0.01 Misid. leptons 9.7 ± 3.4 < 0.1 0.19 ± 0.08 0.36 ± 0.12 Total background 62 ± 5 4.7 ± 1.0 0.65 ± 0.17 1.8 ± 0.3 Observed 76 10 5 2 A data-driven technique is used to estimate the Z +jets and Z γ the luminosity scale using x- y beam-separation scans, following a contribution in both the W H and Z H channels and the contribu- methodology similar to that detailed in Ref. [68], and using the tions from W Z / W γ ∗ and top-quark processes in the Z H channel. LUCID-2 detector for the baseline luminosity measurements [69]. These contributions typically have one misidentified lepton ( Z +jets The impact of the uncertainties on lepton energy (momentum) and Z γ in the W H channel, and W Z / W γ ∗ and t Z /t t̄ W in the scale and resolution, and identification and isolation criteria [54, Z H channel) or two misidentified leptons ( Z +jets and t W /t t̄ in 55,70] is negligible. The experimental uncertainties are varied in a the Z H channel). A control sample where one or two of the lep- correlated way across all background processes and all signal- and ton candidates fail to meet the nominal identification or isolation control-region bins, so that uncertainties in the extrapolation from criteria but satisfy looser identification criteria, referred to as anti- control to signal regions are correctly propagated. The luminosity identified leptons, is used. The contribution from misidentified lep- uncertainty is only applied to background processes that are nor- tons in the SR is then obtained by scaling the number of events malised to theoretical predictions, and to the Higgs boson signal. in the control sample by extrapolation factors measured in a data The theoretical uncertainties are evaluated by comparing nominal sample enriched in Z +jets events. The latter is obtained by select- and alternative event generators and UEPS models as described in ing events with two prompt leptons from a Z boson decay and Section 3 and by varying PDF sets and the QCD renormalisation a loosely identified lepton considered to be the misidentified lep- and factorisation scales. The uncertainty due to the PDF choice for ton candidate. The extrapolation factors are defined as the ratio the signal process is 1% while the uncertainty obtained by using of the number of misidentified lepton candidates that pass the Herwig as an alternative parton shower model is 3 − 10%, depend- nominal identification criteria to the number that pass the anti- ing on the signal region. All uncertainties are propagated through identification criteria. In both the control sample and the data the full analysis chain and treated as being bin-dependent and samples enriched in Z +jets events, the contribution from back- region-dependent, i.e. potentially modifying not only the normali- ground events not estimated with this method is subtracted using sation but also the shape of the BDT output distributions. When- MC expectations. Details of this method can be found in Ref. [67]. ever the influence on the shape is found to be negligible, as in the The uncertainty in the data-driven background processes described case of the PDF and scale variations, only the normalisation uncer- in this section includes the statistical uncertainty in the Z +jets tainties are used. A list of the systematic uncertainty sources and enriched sample, the uncertainty from Z +jets MC modelling, and their impact on the cross-section measurement are shown later in the theory uncertainty from the subtraction of other processes. For Section 8. the Z H channel, which can have events with two prompt leptons and two misidentified leptons, the uncertainty in the extrapolation 8. Results from the control sample to the SRs is also included. A binned likelihood function is constructed as a product of Pois- 7. Systematic uncertainties son probability terms over the eleven bins of the different SRs defined in Section 5. The function has two independent scaling pa- The systematic uncertainties can be categorised into those aris- rameters: the signal strength parameter μ, defined as the ratio of ing from experimental sources and those from theoretical sources. the measured signal yield to that predicted by the SM, for each of The dominant experimental uncertainties come from the misiden- the W H and the Z H processes. Additionally, one Poisson proba- tification of leptons (see Section 6), the mismodelling of the bility term is added for each CR to determine simultaneously the impact-parameter significance, the b-tagging efficiency [61] and normalisation of the corresponding background processes. System- the jet energy scale and resolution [58]. Other sources of uncer- atic uncertainties enter as nuisance parameters in the likelihood tainty are due to the modelling of pile-up, the calibration of the function and their correlations are taken into account. The final missing transverse momentum measurement [62], and the lumi- results are obtained using the profile likelihood method [71]. The nosity measurement. The uncertainty in the combined 2015+2016 resulting post-fit prediction and data yields in the four SRs are integrated luminosity is 2.1%. It is derived from the calibration of shown in Table 5. ATLAS Collaboration / Physics Letters B 798 (2019) 134949 9 Fig. 6. Post-fit BDT-score distributions (a) in the W H Z -dominated SR and (b) for the two-dimensional grid in BDTtt̄ and BDT W Z in the W H Z -depleted SR. The shaded band includes statistical and systematic uncertainties on both signal and background as estimated by the fit. Fig. 8. Two-dimensional likelihood contours of σW H · B H → W W ∗ vs. σ Z H · B H → W W ∗ Fig. 7. Post-fit event yields in the Z H 1-SFOS and 2-SFOS SRs. The shaded band for 68% and 95% confidence level (CL) compared with the prediction from the Stan- includes statistical and systematic uncertainties on both signal and background as dard Model. estimated by the fit. dard deviations. The validity of the asymptotic approximation used Fig. 6 shows the post-fit distribution of BDT scores in the W H Z -dominated and Z -depleted SRs. The post-fit event yields in the in deriving these results was tested using pseudo-experiments. The Z H 1-SFOS and 2-SFOS SRs are shown in Fig. 7. combined signal strength for V H is measured to be The measured signal strengths for the W H and Z H production modes in the H → W W ∗ decay channel are simultaneously deter- μ V H = 2.5+ 0 .8 +0.30 +0.37 + 0 .9 −0.7 (stat.)−0.23 (exp syst.)−0.26 (theo syst.) = 2.5−0.8 mined to be with an expected signal strength of μ V H = 1.0+0.66 −0.54 (stat.) +0.26 +0.22 +0.7 μW H = 2.3+ 1 .1 +0.49 +0.41 + 1 .2 −0.9 (stat.)−0.36 (exp syst.)−0.33 (theo syst.) = 2.3−1.0 , −0.17 (exp syst.)−0.17 (theo syst.) = 1.0−0.6 . The cross-section times branching-fraction values, σ WH · B H → W W ∗ μ Z H = 2.9+ 1 .7 +0.54 +0.66 + 1 .9 −1.3 (stat.)−0.28 (exp syst.)−0.27 (theo syst.) = 2.9−1.3 , and σ Z H · B H → W W ∗ , are simultaneously determined to be: compared to the expected results of μW H = 1.0+ 0.86 −0.69 (stat.) +0.40 +0.32 +1.0 σW H · B H →W W ∗ −0.30 (exp syst.)−0.26 (theo syst.) = 1.0−0.8 and μ Z H = 1.0+1. 3 −0.9 (stat.) +0.41 +0.32 +1.4 = 0.67+ 0.31 +0.14 +0.11 −0.27 (stat.)−0.11 (exp syst.)−0.09 (theo syst.) pb, −0.20 (exp syst.)−0.16 (theo syst.) = 1.0−0.9 . The observed (expected) significances of W H and Z H production modes are 2.6 (1.3) stan- σ Z H · B H →W W ∗ dard deviations and 2.8 (1.2) standard deviations above the SM background, including other Higgs-boson processes, respectively. = 0.54+ 0.31 +0.10 +0.11 −0.24 (stat.)−0.05 (exp syst.)−0.05 (theo syst.) pb. When determining the significance for W H production, the Z H The main contributions to the uncertainties in σ W H · B H → W W ∗ signal-strength parameter is left floating in the fit, and vice versa. and σ Z H · B H → W W ∗ are summarised in Table 6. The predicted The combination of the W H and Z H channels leads to an ob- cross-section times branching-fraction values are 0.293 ± 0.007 pb served (expected) significance for the combined V H production and 0.189 ± 0.007 pb for W H and Z H [72], respectively. The mode of 4.1 (1.9) standard deviations above the SM background, 68% and 95% confidence level two-dimensional contours of σ W H · including other Higgs-boson processes. The p-value with respect B H →W W ∗ and σ Z H · B H →W W ∗ are shown in Fig. 8. The correspond- to the value predicted by the SM corresponds to about two stan- ing one-dimensional results, where the other parameter is left 10 ATLAS Collaboration / Physics Letters B 798 (2019) 134949 Table 6 Breakdown of the main contributions to the total uncertainty in σW H · B H → W W ∗ (left) and σ Z H · B H → W W ∗ (right). The individual sources of systematic uncertainties are grouped together. The sum in quadrature of the individual components differs from the total uncertainty due to correlations between the components. Systematic uncertainties that affect the shape of the fitted distribution are indicated by an asterix. Source σW H · B H →W W ∗ [%] Source σ Z H · B H →W W ∗ [%] Data statistics in SR 43 Data statistics in SR 50 Data statistics in CR 6 Data statistics in CR <1 Theoretical uncertainties 16 Theoretical uncertainties 15 W Z / W γ ∗ (*) 12 Z H signal 14 Top-quark(*) 8 Top-quark 1 W H signal(*) 4 W Z /W γ ∗ <1 Z Z∗ 2 Z Z∗ <1 Experimental uncertainties 12 Experimental uncertainties 7 Impact parameter mismodelling 8 Misidentified leptons 3 Misidentified leptons 8 b-tagging 1 b-tagging 1 MC statistics 9 MC statistics 11 Luminosity 3 Luminosity 2 TOTAL 49 TOTAL 54 floating in the fit, are consistent with the SM predictions within Investissements d’ Avenir Labex and Idex, ANR, France; DFG and 1.3σ for W H and 1.5σ for Z H . AvH Foundation, Germany; Herakleitos, Thales and Aristeia pro- grammes co-financed by EU-ESF and the Greek NSRF, Greece; BSF- 9. Conclusion NSF and GIF, Israel; CERCA Programme Generalitat de Catalunya, Spain; The Royal Society and Leverhulme Trust, United King- Measurements of the inclusive production of a Higgs boson in dom. association with a W or Z boson are presented. Results of the W H The crucial computing support from all WLCG partners is ac- and Z H production cross section times branching fraction for H → knowledged gratefully, in particular from CERN, the ATLAS Tier- W W ∗ are obtained selecting√ the leptonic decays W → ν and 1 facilities at TRIUMF (Canada), NDGF (Denmark, Norway, Swe- Z → , with  = e , μ, in s = 13 TeV proton–proton collisions den), CC-IN2P3 (France), KIT/GridKA (Germany), INFN-CNAF (Italy), recorded with the ATLAS detector at the LHC in a data sample NL-T1 (Netherlands), PIC (Spain), ASGC (Taiwan), RAL (UK) and BNL corresponding to an integrated luminosity of 36.1 fb−1 . The prod- (USA), the Tier-2 facilities worldwide and large non-WLCG resource ucts of the H → W W ∗ branching fraction times the W H and Z H providers. Major contributors of computing resources are listed in cross sections are measured to be 0.67+ 0.31 +0.18 −0.27 (stat.)−0.14 (syst.) pb Ref. [73]. and 0.54+ 0.31 +0.15 −0.24 (stat.)−0.07 (syst.) pb, respectively, compatible with the Standard Model predictions of 0.293 ± 0.007 pb for W H and References 0.189 ± 0.007 pb for Z H within up to 1.5σ . The W H channel with H → W W ∗ is purely sensitive to the H W coupling and this mea- [1] ATLAS Collaboration, Study of ( W / Z ) H production and Higgs boson couplings using H → W W ∗ decays with the ATLAS detector, J. High Energy Phys. 08 surement is to date the most precise measurement of this channel. (2015) 137, arXiv:1506.06641 [hep-ex]. [2] CMS Collaboration, Measurement of Higgs boson production and properties Acknowledgements in the WW decay channel with leptonic final states, J. 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Ferretti 105 , F. Fiedler 99 , A. Filipčič 91 , F. Filthaut 119 , K.D. Finelli 25 , M.C.N. Fiolhais 140a , L. Fiorini 174 , F. Fischer 114 , W.C. Fisher 106 , I. Fleck 151 , P. Fleischmann 105 , R.R.M. Fletcher 137 , T. Flick 182 , B.M. Flierl 114 , L.F. Flores 137 , L.R. Flores Castillo 63a , F.M. Follega 75a,75b , N. Fomin 17 , G.T. Forcolin 75a,75b , A. Formica 145 , F.A. Förster 14 , A.C. Forti 100 , A.G. Foster 21 , M.G. Foti 135 , D. Fournier 132 , H. Fox 89 , P. Francavilla 71a,71b , S. Francescato 72a,72b , M. Franchini 23b,23a , S. Franchino 61a , D. Francis 36 , L. Franconi 20 , M. Franklin 59 , A.N. Fray 92 , B. Freund 109 , W.S. Freund 80b , E.M. Freundlich 47 , D.C. Frizzell 128 , D. Froidevaux 36 , J.A. Frost 135 , C. Fukunaga 164 , E. Fullana Torregrosa 174 , E. Fumagalli 55b,55a , T. Fusayasu 116 , J. Fuster 174 , A. Gabrielli 23b,23a , A. Gabrielli 18 , G.P. Gach 83a , S. Gadatsch 54 , P. Gadow 115 , G. Gagliardi 55b,55a , L.G. Gagnon 109 , C. Galea 27b , B. Galhardo 140a , G.E. Gallardo 135 , E.J. Gallas 135 , B.J. Gallop 144 , P. Gallus 142 , G. Galster 40 , R. Gamboa Goni 92 , K.K. Gan 126 , S. Ganguly 180 , J. Gao 60a , Y. Gao 90 , Y.S. Gao 31,l , C. García 174 , J.E. García Navarro 174 , J.A. García Pascual 15a , C. Garcia-Argos 52 , M. Garcia-Sciveres 18 , R.W. Gardner 37 , N. Garelli 153 , S. Gargiulo 52 , V. Garonne 134 , A. Gaudiello 55b,55a , G. Gaudio 70a , I.L. Gavrilenko 110 , A. Gavrilyuk 111 , C. Gay 175 , G. Gaycken 24 , E.N. Gazis 10 , A.A. Geanta 27b , C.N.P. Gee 144 , J. Geisen 53 , M. Geisen 99 , M.P. Geisler 61a , C. Gemme 55b , M.H. Genest 58 , C. Geng 105 , S. Gentile 72a,72b , S. George 93 , T. Geralis 44 , D. Gerbaudo 14 , L.O. Gerlach 53 , P. Gessinger-Befurt 99 , G. Gessner 47 , S. Ghasemi 151 , M. Ghasemi Bostanabad 176 , M. Ghneimat 24 , A. Ghosh 77 , B. Giacobbe 23b , S. Giagu 72a,72b , N. Giangiacomi 23b,23a , P. Giannetti 71a , A. Giannini 69a,69b , S.M. Gibson 93 , M. Gignac 146 , D. Gillberg 34 , G. Gilles 182 , D.M. Gingrich 3,aw , M.P. Giordani 66a,66c , F.M. Giorgi 23b , P.F. Giraud 145 , G. Giugliarelli 66a,66c , D. Giugni 68a , F. Giuli 73a,73b , S. Gkaitatzis 162 , I. Gkialas 9,h , E.L. Gkougkousis 14 , P. Gkountoumis 10 , L.K. Gladilin 113 , C. Glasman 98 , J. Glatzer 14 , P.C.F. Glaysher 46 , A. Glazov 46 , M. Goblirsch-Kolb 26 , S. Goldfarb 104 , T. Golling 54 , D. Golubkov 123 , A. Gomes 140a,140b , R. Goncalves Gama 53 , R. Gonçalo 140a,140b , G. Gonella 52 , L. Gonella 21 , A. Gongadze 79 , F. Gonnella 21 , J.L. Gonski 59 , S. González de la Hoz 174 , S. Gonzalez-Sevilla 54 , G.R. Gonzalvo Rodriguez 174 , L. Goossens 36 , P.A. Gorbounov 111 , H.A. Gordon 29 , B. Gorini 36 , E. Gorini 67a,67b , A. Gorišek 91 , A.T. Goshaw 49 , C. Gössling 47 , M.I. Gostkin 79 , C.A. Gottardo 24 , M. Gouighri 35b , D. Goujdami 35c , A.G. Goussiou 148 , N. Govender 33b,a , C. Goy 5 , E. Gozani 160 , I. Grabowska-Bold 83a , E.C. Graham 90 , J. Gramling 171 , E. Gramstad 134 , S. Grancagnolo 19 , M. Grandi 156 , V. Gratchev 138 , P.M. Gravila 27f , F.G. Gravili 67a,67b , ATLAS Collaboration / Physics Letters B 798 (2019) 134949 15 C. Gray 57 , H.M. Gray 18 , C. Grefe 24 , K. Gregersen 96 , I.M. Gregor 46 , P. Grenier 153 , K. Grevtsov 46 , N.A. Grieser 128 , J. Griffiths 8 , A.A. Grillo 146 , K. Grimm 31,k , S. Grinstein 14,w , J.-F. Grivaz 132 , S. Groh 99 , E. Gross 180 , J. Grosse-Knetter 53 , Z.J. Grout 94 , C. Grud 105 , A. Grummer 118 , L. Guan 105 , W. Guan 181 , J. Guenther 36 , A. Guerguichon 132 , F. Guescini 168a , D. Guest 171 , R. Gugel 52 , B. Gui 126 , T. Guillemin 5 , S. Guindon 36 , U. Gul 57 , J. Guo 60c , W. Guo 105 , Y. Guo 60a,r , Z. Guo 101 , R. Gupta 46 , S. Gurbuz 12c , G. Gustavino 128 , P. Gutierrez 128 , C. Gutschow 94 , C. Guyot 145 , M.P. Guzik 83a , C. Gwenlan 135 , C.B. Gwilliam 90 , A. Haas 124 , C. Haber 18 , H.K. Hadavand 8 , N. Haddad 35e , A. Hadef 60a , S. Hageböck 36 , M. Hagihara 169 , M. Haleem 177 , J. Haley 129 , G. Halladjian 106 , G.D. Hallewell 101 , K. Hamacher 182 , P. Hamal 130 , K. Hamano 176 , H. Hamdaoui 35e , G.N. Hamity 149 , K. Han 60a,aj , L. Han 60a , S. Han 15a,15d , K. Hanagaki 81,u , M. Hance 146 , D.M. Handl 114 , B. Haney 137 , R. Hankache 136 , P. Hanke 61a , E. Hansen 96 , J.B. Hansen 40 , J.D. Hansen 40 , M.C. Hansen 24 , P.H. Hansen 40 , E.C. Hanson 100 , K. Hara 169 , A.S. Hard 181 , T. Harenberg 182 , S. Harkusha 107 , P.F. Harrison 178 , N.M. Hartmann 114 , Y. Hasegawa 150 , A. Hasib 50 , S. Hassani 145 , S. Haug 20 , R. Hauser 106 , L.B. Havener 39 , M. Havranek 142 , C.M. Hawkes 21 , R.J. Hawkings 36 , D. Hayden 106 , C. Hayes 155 , R.L. Hayes 175 , C.P. Hays 135 , J.M. Hays 92 , H.S. Hayward 90 , S.J. Haywood 144 , F. He 60a , M.P. Heath 50 , V. Hedberg 96 , L. Heelan 8 , S. Heer 24 , K.K. Heidegger 52 , J. Heilman 34 , S. Heim 46 , T. Heim 18 , B. Heinemann 46,ar , J.J. Heinrich 131 , L. Heinrich 36 , C. Heinz 56 , J. Hejbal 141 , L. Helary 61b , A. Held 175 , S. Hellesund 134 , C.M. Helling 146 , S. Hellman 45a,45b , C. Helsens 36 , R.C.W. Henderson 89 , Y. Heng 181 , S. Henkelmann 175 , A.M. Henriques Correia 36 , G.H. Herbert 19 , H. Herde 26 , V. Herget 177 , Y. Hernández Jiménez 33c , H. Herr 99 , M.G. Herrmann 114 , T. Herrmann 48 , G. Herten 52 , R. Hertenberger 114 , L. Hervas 36 , T.C. Herwig 137 , G.G. Hesketh 94 , N.P. Hessey 168a , A. Higashida 163 , S. Higashino 81 , E. Higón-Rodriguez 174 , K. Hildebrand 37 , E. Hill 176 , J.C. Hill 32 , K.K. Hill 29 , K.H. Hiller 46 , S.J. Hillier 21 , M. Hils 48 , I. Hinchliffe 18 , F. Hinterkeuser 24 , M. Hirose 133 , S. Hirose 52 , D. Hirschbuehl 182 , B. Hiti 91 , O. Hladik 141 , D.R. Hlaluku 33c , X. Hoad 50 , J. Hobbs 155 , N. Hod 180 , M.C. Hodgkinson 149 , A. Hoecker 36 , F. Hoenig 114 , D. Hohn 52 , D. Hohov 132 , T.R. Holmes 37 , M. Holzbock 114 , L.B.A.H Hommels 32 , S. Honda 169 , T. Honda 81 , T.M. Hong 139 , A. Hönle 115 , B.H. Hooberman 173 , W.H. Hopkins 6 , Y. Horii 117 , P. Horn 48 , A.J. Horton 152 , L.A. Horyn 37 , J-Y. Hostachy 58 , A. Hostiuc 148 , S. Hou 158 , A. Hoummada 35a , J. Howarth 100 , J. Hoya 88 , M. Hrabovsky 130 , J. Hrdinka 76 , I. Hristova 19 , J. Hrivnac 132 , A. Hrynevich 108 , T. Hryn’ova 5 , P.J. Hsu 64 , S.-C. Hsu 148 , Q. Hu 29 , S. Hu 60c , Y. Huang 15a , Z. Hubacek 142 , F. Hubaut 101 , M. Huebner 24 , F. Huegging 24 , T.B. Huffman 135 , M. Huhtinen 36 , R.F.H. Hunter 34 , P. Huo 155 , A.M. Hupe 34 , N. Huseynov 79,ae , J. Huston 106 , J. Huth 59 , R. Hyneman 105 , S. Hyrych 28a , G. Iacobucci 54 , G. Iakovidis 29 , I. Ibragimov 151 , L. Iconomidou-Fayard 132 , Z. Idrissi 35e , P.I. Iengo 36 , R. Ignazzi 40 , O. Igonkina 120,y , R. Iguchi 163 , T. Iizawa 54 , Y. Ikegami 81 , M. Ikeno 81 , D. Iliadis 162 , N. Ilic 119 , F. Iltzsche 48 , G. Introzzi 70a,70b , M. Iodice 74a , K. Iordanidou 39 , V. Ippolito 72a,72b , M.F. Isacson 172 , N. Ishijima 133 , M. Ishino 163 , M. Ishitsuka 165 , W. Islam 129 , C. Issever 135 , S. Istin 160 , F. Ito 169 , J.M. Iturbe Ponce 63a , R. Iuppa 75a,75b , A. Ivina 180 , H. Iwasaki 81 , J.M. Izen 43 , V. Izzo 69a , P. Jacka 141 , P. Jackson 1 , R.M. Jacobs 24 , V. Jain 2 , G. Jäkel 182 , K.B. Jakobi 99 , K. Jakobs 52 , S. Jakobsen 76 , T. Jakoubek 141 , J. Jamieson 57 , K.W. Janas 83a , R. Jansky 54 , J. Janssen 24 , M. Janus 53 , P.A. Janus 83a , G. Jarlskog 96 , N. Javadov 79,ae , T. Javůrek 36 , M. Javurkova 52 , F. Jeanneau 145 , L. Jeanty 131 , J. Jejelava 159a,af , A. Jelinskas 178 , P. Jenni 52,b , J. Jeong 46 , N. Jeong 46 , S. Jézéquel 5 , H. Ji 181 , J. Jia 155 , H. Jiang 78 , Y. Jiang 60a , Z. Jiang 153,p , S. Jiggins 52 , F.A. Jimenez Morales 38 , J. Jimenez Pena 174 , S. Jin 15c , A. Jinaru 27b , O. Jinnouchi 165 , H. Jivan 33c , P. Johansson 149 , K.A. Johns 7 , C.A. Johnson 65 , K. Jon-And 45a,45b , R.W.L. Jones 89 , S.D. Jones 156 , S. Jones 7 , T.J. Jones 90 , J. Jongmanns 61a , P.M. Jorge 140a , J. Jovicevic 36 , X. Ju 18 , J.J. Junggeburth 115 , A. Juste Rozas 14,w , A. Kaczmarska 84 , M. Kado 72a,72b , H. Kagan 126 , M. Kagan 153 , C. Kahra 99 , T. Kaji 179 , E. Kajomovitz 160 , C.W. Kalderon 96 , A. Kaluza 99 , A. Kamenshchikov 123 , L. Kanjir 91 , Y. Kano 163 , V.A. Kantserov 112 , J. Kanzaki 81 , L.S. Kaplan 181 , D. Kar 33c , M.J. Kareem 168b , E. Karentzos 10 , S.N. Karpov 79 , Z.M. Karpova 79 , V. Kartvelishvili 89 , A.N. Karyukhin 123 , L. Kashif 181 , R.D. Kass 126 , A. Kastanas 45a,45b , Y. Kataoka 163 , C. Kato 60d,60c , J. Katzy 46 , K. Kawade 82 , K. Kawagoe 87 , T. Kawaguchi 117 , T. Kawamoto 163 , G. Kawamura 53 , E.F. Kay 176 , V.F. Kazanin 122b,122a , R. Keeler 176 , R. Kehoe 42 , J.S. Keller 34 , E. Kellermann 96 , D. Kelsey 156 , J.J. Kempster 21 , J. Kendrick 21 , O. Kepka 141 , S. Kersten 182 , B.P. Kerševan 91 , S. Ketabchi Haghighat 167 , M. Khader 173 , F. Khalil-Zada 13 , M. Khandoga 145 , A. Khanov 129 , A.G. Kharlamov 122b,122a , T. Kharlamova 122b,122a , E.E. Khoda 175 , A. Khodinov 166 , T.J. Khoo 54 , E. Khramov 79 , J. Khubua 159b , S. Kido 82 , M. Kiehn 54 , C.R. Kilby 93 , 16 ATLAS Collaboration / Physics Letters B 798 (2019) 134949 Y.K. Kim 37 , N. Kimura 66a,66c , O.M. Kind 19 , B.T. King 90,∗ , D. Kirchmeier 48 , J. Kirk 144 , A.E. Kiryunin 115 , T. Kishimoto 163 , D.P. Kisliuk 167 , V. Kitali 46 , O. Kivernyk 5 , E. Kladiva 28b,∗ , T. Klapdor-Kleingrothaus 52 , M.H. Klein 105 , M. Klein 90 , U. Klein 90 , K. Kleinknecht 99 , P. Klimek 121 , A. Klimentov 29 , T. Klingl 24 , T. Klioutchnikova 36 , F.F. Klitzner 114 , P. Kluit 120 , S. Kluth 115 , E. Kneringer 76 , E.B.F.G. Knoops 101 , A. Knue 52 , D. Kobayashi 87 , T. Kobayashi 163 , M. Kobel 48 , M. Kocian 153 , P. Kodys 143 , P.T. Koenig 24 , T. Koffas 34 , N.M. Köhler 115 , T. Koi 153 , M. Kolb 61b , I. Koletsou 5 , T. Komarek 130 , T. Kondo 81 , N. Kondrashova 60c , K. Köneke 52 , A.C. König 119 , T. Kono 125 , R. Konoplich 124,am , V. Konstantinides 94 , N. Konstantinidis 94 , B. Konya 96 , R. Kopeliansky 65 , S. Koperny 83a , K. Korcyl 84 , K. Kordas 162 , G. Koren 161 , A. Korn 94 , I. Korolkov 14 , E.V. Korolkova 149 , N. Korotkova 113 , O. Kortner 115 , S. Kortner 115 , T. Kosek 143 , V.V. Kostyukhin 24 , A. Kotwal 49 , A. Koulouris 10 , A. Kourkoumeli-Charalampidi 70a,70b , C. Kourkoumelis 9 , E. Kourlitis 149 , V. Kouskoura 29 , A.B. Kowalewska 84 , R. Kowalewski 176 , C. Kozakai 163 , W. Kozanecki 145 , A.S. Kozhin 123 , V.A. Kramarenko 113 , G. Kramberger 91 , D. Krasnopevtsev 60a , M.W. Krasny 136 , A. Krasznahorkay 36 , D. Krauss 115 , J.A. Kremer 83a , J. Kretzschmar 90 , P. Krieger 167 , F. Krieter 114 , A. Krishnan 61b , K. Krizka 18 , K. Kroeninger 47 , H. Kroha 115 , J. Kroll 141 , J. Kroll 137 , J. Krstic 16 , U. Kruchonak 79 , H. Krüger 24 , N. Krumnack 78 , M.C. Kruse 49 , T. Kubota 104 , S. Kuday 4b , J.T. Kuechler 46 , S. Kuehn 36 , A. Kugel 61a , T. Kuhl 46 , V. Kukhtin 79 , R. Kukla 101 , Y. Kulchitsky 107,ai , S. Kuleshov 147b , Y.P. Kulinich 173 , M. Kuna 58 , T. Kunigo 85 , A. Kupco 141 , T. Kupfer 47 , O. Kuprash 52 , H. Kurashige 82 , L.L. Kurchaninov 168a , Y.A. Kurochkin 107 , A. Kurova 112 , M.G. Kurth 15a,15d , E.S. Kuwertz 36 , M. Kuze 165 , A.K. Kvam 148 , J. Kvita 130 , T. Kwan 103 , A. La Rosa 115 , L. La Rotonda 41b,41a , F. La Ruffa 41b,41a , C. Lacasta 174 , F. Lacava 72a,72b , D.P.J. Lack 100 , H. Lacker 19 , D. Lacour 136 , E. Ladygin 79 , R. Lafaye 5 , B. Laforge 136 , T. Lagouri 33c , S. Lai 53 , S. Lammers 65 , W. Lampl 7 , C. Lampoudis 162 , E. Lançon 29 , U. Landgraf 52 , M.P.J. Landon 92 , M.C. Lanfermann 54 , V.S. Lang 46 , J.C. Lange 53 , R.J. Langenberg 36 , A.J. Lankford 171 , F. Lanni 29 , K. Lantzsch 24 , A. Lanza 70a , A. Lapertosa 55b,55a , S. Laplace 136 , J.F. Laporte 145 , T. Lari 68a , F. Lasagni Manghi 23b,23a , M. Lassnig 36 , T.S. Lau 63a , A. Laudrain 132 , A. Laurier 34 , M. Lavorgna 69a,69b , M. Lazzaroni 68a,68b , B. Le 104 , O. Le Dortz 136 , E. Le Guirriec 101 , M. LeBlanc 7 , T. LeCompte 6 , F. Ledroit-Guillon 58 , C.A. Lee 29 , G.R. Lee 17 , L. Lee 59 , S.C. Lee 158 , S.J. Lee 34 , B. Lefebvre 168a , M. Lefebvre 176 , F. Legger 114 , C. Leggett 18 , K. Lehmann 152 , N. Lehmann 182 , G. Lehmann Miotto 36 , W.A. Leight 46 , A. Leisos 162,v , M.A.L. Leite 80d , R. Leitner 143 , D. Lellouch 180,∗ , K.J.C. Leney 42 , T. Lenz 24 , B. Lenzi 36 , R. Leone 7 , S. Leone 71a , C. Leonidopoulos 50 , A. Leopold 136 , G. Lerner 156 , C. Leroy 109 , R. Les 167 , C.G. Lester 32 , M. Levchenko 138 , J. Levêque 5 , D. Levin 105 , L.J. Levinson 180 , D.J. Lewis 21 , B. Li 15b , B. Li 105 , C-Q. Li 60a , F. Li 60c , H. Li 60a , H. Li 60b , J. Li 60c , K. Li 153 , L. Li 60c , M. Li 15a , Q. Li 15a,15d , Q.Y. Li 60a , S. Li 60d,60c , X. Li 46 , Y. Li 46 , Z. Li 60b , Z. Liang 15a , B. Liberti 73a , A. Liblong 167 , K. Lie 63c , S. Liem 120 , C.Y. Lin 32 , K. Lin 106 , T.H. Lin 99 , R.A. Linck 65 , J.H. Lindon 21 , A.L. Lionti 54 , E. Lipeles 137 , A. Lipniacka 17 , M. Lisovyi 61b , T.M. Liss 173,at , A. Lister 175 , A.M. Litke 146 , J.D. Little 8 , B. Liu 78,ab , B.L Liu 6 , H.B. Liu 29 , H. Liu 105 , J.B. Liu 60a , J.K.K. Liu 135 , K. Liu 136 , M. Liu 60a , P. Liu 18 , Y. Liu 15a,15d , Y.L. Liu 105 , Y.W. Liu 60a , M. Livan 70a,70b , A. Lleres 58 , J. Llorente Merino 15a , S.L. Lloyd 92 , C.Y. Lo 63b , F. Lo Sterzo 42 , E.M. Lobodzinska 46 , P. Loch 7 , S. Loffredo 73a,73b , T. Lohse 19 , K. Lohwasser 149 , M. Lokajicek 141 , J.D. Long 173 , R.E. Long 89 , L. Longo 36 , K.A. Looper 126 , J.A. Lopez 147b , I. Lopez Paz 100 , A. Lopez Solis 149 , J. Lorenz 114 , N. Lorenzo Martinez 5 , M. Losada 22 , P.J. Lösel 114 , A. Lösle 52 , X. Lou 46 , X. Lou 15a , A. Lounis 132 , J. Love 6 , P.A. Love 89 , J.J. Lozano Bahilo 174 , M. Lu 60a , Y.J. Lu 64 , H.J. Lubatti 148 , C. Luci 72a,72b , A. Lucotte 58 , C. Luedtke 52 , F. Luehring 65 , I. Luise 136 , L. Luminari 72a , B. Lund-Jensen 154 , M.S. Lutz 102 , D. Lynn 29 , R. Lysak 141 , E. Lytken 96 , F. Lyu 15a , V. Lyubushkin 79 , T. Lyubushkina 79 , H. Ma 29 , L.L. Ma 60b , Y. Ma 60b , G. Maccarrone 51 , A. Macchiolo 115 , C.M. Macdonald 149 , J. Machado Miguens 137 , D. Madaffari 174 , R. Madar 38 , W.F. Mader 48 , N. Madysa 48 , J. Maeda 82 , K. Maekawa 163 , S. Maeland 17 , T. Maeno 29 , M. Maerker 48 , A.S. Maevskiy 113 , V. Magerl 52 , N. Magini 78 , D.J. Mahon 39 , C. Maidantchik 80b , T. Maier 114 , A. Maio 140a,140b,140d , O. Majersky 28a , S. Majewski 131 , Y. Makida 81 , N. Makovec 132 , B. Malaescu 136 , Pa. Malecki 84 , V.P. Maleev 138 , F. Malek 58 , U. Mallik 77 , D. Malon 6 , C. Malone 32 , S. Maltezos 10 , S. Malyukov 36 , J. Mamuzic 174 , G. Mancini 51 , I. Mandić 91 , L. Manhaes de Andrade Filho 80a , I.M. Maniatis 162 , J. Manjarres Ramos 48 , K.H. Mankinen 96 , A. Mann 114 , A. Manousos 76 , B. Mansoulie 145 , I. Manthos 162 , S. Manzoni 120 , A. Marantis 162 , G. Marceca 30 , L. Marchese 135 , G. Marchiori 136 , M. Marcisovsky 141 , C. Marcon 96 , C.A. Marin Tobon 36 , M. Marjanovic 38 , F. Marroquim 80b , Z. Marshall 18 , M.U.F Martensson 172 , S. Marti-Garcia 174 , ATLAS Collaboration / Physics Letters B 798 (2019) 134949 17 C.B. Martin 126 , T.A. Martin 178 , V.J. Martin 50 , B. Martin dit Latour 17 , L. Martinelli 74a,74b , M. Martinez 14,w , V.I. Martinez Outschoorn 102 , S. Martin-Haugh 144 , V.S. Martoiu 27b , A.C. Martyniuk 94 , A. Marzin 36 , S.R. Maschek 115 , L. Masetti 99 , T. Mashimo 163 , R. Mashinistov 110 , J. Masik 100 , A.L. Maslennikov 122b,122a , L.H. Mason 104 , L. Massa 73a,73b , P. Massarotti 69a,69b , P. Mastrandrea 71a,71b , A. Mastroberardino 41b,41a , T. Masubuchi 163 , A. Matic 114 , P. Mättig 24 , J. Maurer 27b , B. Maček 91 , S.J. Maxfield 90 , D.A. Maximov 122b,122a , R. Mazini 158 , I. Maznas 162 , S.M. Mazza 146 , S.P. Mc Kee 105 , T.G. McCarthy 115 , L.I. McClymont 94 , W.P. McCormack 18 , E.F. McDonald 104 , J.A. Mcfayden 36 , M.A. McKay 42 , K.D. McLean 176 , S.J. McMahon 144 , P.C. McNamara 104 , C.J. McNicol 178 , R.A. McPherson 176,ac , J.E. Mdhluli 33c , Z.A. Meadows 102 , S. Meehan 148 , T. Megy 52 , S. Mehlhase 114 , A. Mehta 90 , T. Meideck 58 , B. Meirose 43 , D. Melini 174 , B.R. Mellado Garcia 33c , J.D. Mellenthin 53 , M. Melo 28a , F. Meloni 46 , A. Melzer 24 , S.B. Menary 100 , E.D. Mendes Gouveia 140a,140e , L. Meng 36 , X.T. Meng 105 , S. Menke 115 , E. Meoni 41b,41a , S. Mergelmeyer 19 , S.A.M. Merkt 139 , C. Merlassino 20 , P. Mermod 54 , L. Merola 69a,69b , C. Meroni 68a , O. Meshkov 113,110 , J.K.R. Meshreki 151 , A. Messina 72a,72b , J. Metcalfe 6 , A.S. Mete 171 , C. Meyer 65 , J. Meyer 160 , J-P. Meyer 145 , H. Meyer Zu Theenhausen 61a , F. Miano 156 , R.P. Middleton 144 , L. Mijović 50 , G. Mikenberg 180 , M. Mikestikova 141 , M. Mikuž 91 , H. Mildner 149 , M. Milesi 104 , A. Milic 167 , D.A. Millar 92 , D.W. Miller 37 , A. Milov 180 , D.A. Milstead 45a,45b , R.A. Mina 153,p , A.A. Minaenko 123 , M. Miñano Moya 174 , I.A. Minashvili 159b , A.I. Mincer 124 , B. Mindur 83a , M. Mineev 79 , Y. Minegishi 163 , Y. Ming 181 , L.M. Mir 14 , A. Mirto 67a,67b , K.P. Mistry 137 , T. Mitani 179 , J. Mitrevski 114 , V.A. Mitsou 174 , M. Mittal 60c , A. Miucci 20 , P.S. Miyagawa 149 , A. Mizukami 81 , J.U. Mjörnmark 96 , T. Mkrtchyan 184 , M. Mlynarikova 143 , T. Moa 45a,45b , K. Mochizuki 109 , P. Mogg 52 , S. Mohapatra 39 , R. Moles-Valls 24 , M.C. Mondragon 106 , K. Mönig 46 , J. Monk 40 , E. Monnier 101 , A. Montalbano 152 , J. Montejo Berlingen 36 , M. Montella 94 , F. Monticelli 88 , S. Monzani 68a , N. Morange 132 , D. Moreno 22 , M. Moreno Llácer 36 , C. Moreno Martinez 14 , P. Morettini 55b , M. Morgenstern 120 , S. Morgenstern 48 , D. Mori 152 , M. Morii 59 , M. Morinaga 179 , V. Morisbak 134 , A.K. Morley 36 , G. Mornacchi 36 , A.P. Morris 94 , L. Morvaj 155 , P. Moschovakos 36 , B. Moser 120 , M. Mosidze 159b , T. Moskalets 145 , H.J. Moss 149 , J. Moss 31,m , K. Motohashi 165 , E. Mountricha 36 , E.J.W. Moyse 102 , S. Muanza 101 , J. Mueller 139 , R.S.P. Mueller 114 , D. Muenstermann 89 , G.A. Mullier 96 , J.L. Munoz Martinez 14 , F.J. Munoz Sanchez 100 , P. Murin 28b , W.J. Murray 178,144 , A. Murrone 68a,68b , M. Muškinja 18 , C. Mwewa 33a , A.G. Myagkov 123,an , J. Myers 131 , M. Myska 142 , B.P. Nachman 18 , O. Nackenhorst 47 , A. Nag Nag 48 , K. Nagai 135 , K. Nagano 81 , Y. Nagasaka 62 , M. Nagel 52 , E. Nagy 101 , A.M. Nairz 36 , Y. Nakahama 117 , K. Nakamura 81 , T. Nakamura 163 , I. Nakano 127 , H. Nanjo 133 , F. Napolitano 61a , R.F. Naranjo Garcia 46 , R. Narayan 11 , D.I. Narrias Villar 61a , I. Naryshkin 138 , T. Naumann 46 , G. Navarro 22 , H.A. Neal 105,∗ , P.Y. Nechaeva 110 , F. Nechansky 46 , T.J. Neep 21 , A. Negri 70a,70b , M. Negrini 23b , C. Nellist 53 , M.E. Nelson 135 , S. Nemecek 141 , P. Nemethy 124 , M. Nessi 36,d , M.S. Neubauer 173 , M. Neumann 182 , P.R. Newman 21 , T.Y. Ng 63c , Y.S. Ng 19 , Y.W.Y. Ng 171 , H.D.N. Nguyen 101 , T. Nguyen Manh 109 , E. Nibigira 38 , R.B. Nickerson 135 , R. Nicolaidou 145 , D.S. Nielsen 40 , J. Nielsen 146 , N. Nikiforou 11 , V. Nikolaenko 123,an , I. Nikolic-Audit 136 , K. Nikolopoulos 21 , P. Nilsson 29 , H.R. Nindhito 54 , Y. Ninomiya 81 , A. Nisati 72a , N. Nishu 60c , R. Nisius 115 , I. Nitsche 47 , T. Nitta 179 , T. Nobe 163 , Y. Noguchi 85 , M. Nomachi 133 , I. Nomidis 136 , M.A. Nomura 29 , M. Nordberg 36 , N. Norjoharuddeen 135 , T. Novak 91 , O. Novgorodova 48 , R. Novotny 142 , L. Nozka 130 , K. Ntekas 171 , E. Nurse 94 , F.G. Oakham 34,aw , H. Oberlack 115 , J. Ocariz 136 , A. Ochi 82 , I. Ochoa 39 , J.P. Ochoa-Ricoux 147a , K. O’Connor 26 , S. Oda 87 , S. Odaka 81 , S. Oerdek 53 , A. Ogrodnik 83a , A. Oh 100 , S.H. Oh 49 , C.C. Ohm 154 , H. Oide 55b,55a , M.L. Ojeda 167 , H. Okawa 169 , Y. Okazaki 85 , Y. Okumura 163 , T. Okuyama 81 , A. Olariu 27b , L.F. Oleiro Seabra 140a , S.A. Olivares Pino 147a , D. Oliveira Damazio 29 , J.L. Oliver 1 , M.J.R. Olsson 171 , A. Olszewski 84 , J. Olszowska 84 , D.C. O’Neil 152 , A. Onofre 140a,140e , K. Onogi 117 , P.U.E. Onyisi 11 , H. Oppen 134 , M.J. Oreglia 37 , G.E. Orellana 88 , Y. Oren 161 , D. Orestano 74a,74b , N. Orlando 14 , R.S. Orr 167 , V. O’Shea 57 , R. Ospanov 60a , G. Otero y Garzon 30 , H. Otono 87 , M. Ouchrif 35d , F. Ould-Saada 134 , A. Ouraou 145 , Q. Ouyang 15a , M. Owen 57 , R.E. Owen 21 , V.E. Ozcan 12c , N. Ozturk 8 , J. Pacalt 130 , H.A. Pacey 32 , K. Pachal 49 , A. Pacheco Pages 14 , C. Padilla Aranda 14 , S. Pagan Griso 18 , M. Paganini 183 , G. Palacino 65 , S. Palazzo 50 , S. Palestini 36 , M. Palka 83b , D. Pallin 38 , I. Panagoulias 10 , C.E. Pandini 36 , J.G. Panduro Vazquez 93 , P. Pani 46 , G. Panizzo 66a,66c , L. Paolozzi 54 , C. Papadatos 109 , K. Papageorgiou 9,h , A. Paramonov 6 , D. Paredes Hernandez 63b , S.R. Paredes Saenz 135 , B. Parida 166 , T.H. Park 167 , 18 ATLAS Collaboration / Physics Letters B 798 (2019) 134949 A.J. Parker 89 , M.A. Parker 32 , F. Parodi 55b,55a , E.W.P. Parrish 121 , J.A. Parsons 39 , U. Parzefall 52 , L. Pascual Dominguez 136 , V.R. Pascuzzi 167 , J.M.P. Pasner 146 , E. Pasqualucci 72a , S. Passaggio 55b , F. Pastore 93 , P. Pasuwan 45a,45b , S. Pataraia 99 , J.R. Pater 100 , A. Pathak 181 , T. Pauly 36 , B. Pearson 115 , M. Pedersen 134 , L. Pedraza Diaz 119 , R. Pedro 140a , T. Peiffer 53 , S.V. Peleganchuk 122b,122a , O. Penc 141 , H. Peng 60a , B.S. Peralva 80a , M.M. Perego 132 , A.P. Pereira Peixoto 140a , D.V. Perepelitsa 29 , F. Peri 19 , L. Perini 68a,68b , H. Pernegger 36 , S. Perrella 69a,69b , K. Peters 46 , R.F.Y. Peters 100 , B.A. Petersen 36 , T.C. Petersen 40 , E. Petit 101 , A. Petridis 1 , C. Petridou 162 , P. Petroff 132 , M. Petrov 135 , F. Petrucci 74a,74b , M. Pettee 183 , N.E. Pettersson 102 , K. Petukhova 143 , A. Peyaud 145 , R. Pezoa 147b , L. Pezzotti 70a,70b , T. Pham 104 , F.H. Phillips 106 , P.W. Phillips 144 , M.W. Phipps 173 , G. Piacquadio 155 , E. Pianori 18 , A. Picazio 102 , R.H. Pickles 100 , R. Piegaia 30 , D. Pietreanu 27b , J.E. Pilcher 37 , A.D. Pilkington 100 , M. Pinamonti 73a,73b , J.L. Pinfold 3 , M. Pitt 180 , L. Pizzimento 73a,73b , M.-A. Pleier 29 , V. Pleskot 143 , E. Plotnikova 79 , D. Pluth 78 , P. Podberezko 122b,122a , R. Poettgen 96 , R. Poggi 54 , L. Poggioli 132 , I. Pogrebnyak 106 , D. Pohl 24 , I. Pokharel 53 , G. Polesello 70a , A. Poley 18 , A. Policicchio 72a,72b , R. Polifka 143 , A. Polini 23b , C.S. Pollard 46 , V. Polychronakos 29 , D. Ponomarenko 112 , L. Pontecorvo 36 , S. Popa 27a , G.A. Popeneciu 27d , D.M. Portillo Quintero 58 , S. Pospisil 142 , K. Potamianos 46 , I.N. Potrap 79 , C.J. Potter 32 , H. Potti 11 , T. Poulsen 96 , J. Poveda 36 , T.D. Powell 149 , G. Pownall 46 , M.E. Pozo Astigarraga 36 , P. Pralavorio 101 , S. Prell 78 , D. Price 100 , M. Primavera 67a , S. Prince 103 , M.L. Proffitt 148 , N. Proklova 112 , K. Prokofiev 63c , F. Prokoshin 147b , S. Protopopescu 29 , J. Proudfoot 6 , M. Przybycien 83a , D. Pudzha 138 , A. Puri 173 , P. Puzo 132 , J. Qian 105 , Y. Qin 100 , A. Quadt 53 , M. Queitsch-Maitland 46 , A. Qureshi 1 , P. Rados 104 , F. Ragusa 68a,68b , G. Rahal 97 , J.A. Raine 54 , S. Rajagopalan 29 , A. Ramirez Morales 92 , K. Ran 15a,15d , T. Rashid 132 , S. Raspopov 5 , M.G. Ratti 68a,68b , D.M. Rauch 46 , F. Rauscher 114 , S. Rave 99 , B. Ravina 149 , I. Ravinovich 180 , J.H. Rawling 100 , M. Raymond 36 , A.L. Read 134 , N.P. Readioff 58 , M. Reale 67a,67b , D.M. Rebuzzi 70a,70b , A. Redelbach 177 , G. Redlinger 29 , K. Reeves 43 , L. Rehnisch 19 , J. Reichert 137 , D. Reikher 161 , A. Reiss 99 , A. Rej 151 , C. Rembser 36 , M. Renda 27b , M. Rescigno 72a , S. Resconi 68a , E.D. Resseguie 137 , S. Rettie 175 , E. Reynolds 21 , O.L. Rezanova 122b,122a , P. Reznicek 143 , E. Ricci 75a,75b , R. Richter 115 , S. Richter 46 , E. Richter-Was 83b , O. Ricken 24 , M. Ridel 136 , P. Rieck 115 , C.J. Riegel 182 , O. Rifki 46 , M. Rijssenbeek 155 , A. Rimoldi 70a,70b , M. Rimoldi 20 , L. Rinaldi 23b , G. Ripellino 154 , B. Ristić 89 , E. Ritsch 36 , I. Riu 14 , J.C. Rivera Vergara 147a , F. Rizatdinova 129 , E. Rizvi 92 , C. Rizzi 36 , R.T. Roberts 100 , S.H. Robertson 103,ac , M. Robin 46 , D. Robinson 32 , J.E.M. Robinson 46 , A. Robson 57 , E. Rocco 99 , C. Roda 71a,71b , S. Rodriguez Bosca 174 , A. Rodriguez Perez 14 , D. Rodriguez Rodriguez 174 , A.M. Rodríguez Vera 168b , S. Roe 36 , O. Røhne 134 , R. Röhrig 115 , C.P.A. Roland 65 , J. Roloff 59 , A. Romaniouk 112 , M. Romano 23b,23a , N. Rompotis 90 , M. Ronzani 124 , L. Roos 136 , S. Rosati 72a , K. Rosbach 52 , N-A. Rosien 53 , G. Rosin 102 , B.J. Rosser 137 , E. Rossi 46 , E. Rossi 74a,74b , E. Rossi 69a,69b , L.P. Rossi 55b , L. Rossini 68a,68b , R. Rosten 14 , M. Rotaru 27b , J. Rothberg 148 , D. Rousseau 132 , G. Rovelli 70a,70b , D. Roy 33c , A. Rozanov 101 , Y. Rozen 160 , X. Ruan 33c , F. Rubbo 153 , F. Rühr 52 , A. Ruiz-Martinez 174 , A. Rummler 36 , Z. Rurikova 52 , N.A. Rusakovich 79 , H.L. Russell 103 , L. Rustige 38,47 , J.P. Rutherfoord 7 , E.M. Rüttinger 46,j , Y.F. Ryabov 138 , M. Rybar 39 , G. Rybkin 132 , A. Ryzhov 123 , G.F. Rzehorz 53 , P. Sabatini 53 , G. Sabato 120 , S. Sacerdoti 132 , H.F-W. Sadrozinski 146 , R. Sadykov 79 , F. Safai Tehrani 72a , B. Safarzadeh Samani 156 , P. Saha 121 , S. Saha 103 , M. Sahinsoy 61a , A. Sahu 182 , M. Saimpert 46 , M. Saito 163 , T. Saito 163 , H. Sakamoto 163 , A. Sakharov 124,am , D. Salamani 54 , G. Salamanna 74a,74b , J.E. Salazar Loyola 147b , P.H. Sales De Bruin 172 , D. Salihagic 115,∗ , A. Salnikov 153 , J. Salt 174 , D. Salvatore 41b,41a , F. Salvatore 156 , A. Salvucci 63a,63b,63c , A. Salzburger 36 , J. Samarati 36 , D. Sammel 52 , D. Sampsonidis 162 , D. Sampsonidou 162 , J. Sánchez 174 , A. Sanchez Pineda 66a,66c , H. Sandaker 134 , C.O. Sander 46 , I.G. Sanderswood 89 , M. Sandhoff 182 , C. Sandoval 22 , D.P.C. Sankey 144 , M. Sannino 55b,55a , Y. Sano 117 , A. Sansoni 51 , C. Santoni 38 , H. Santos 140a,140b , S.N. Santpur 18 , A. Santra 174 , A. Sapronov 79 , J.G. Saraiva 140a,140d , O. Sasaki 81 , K. Sato 169 , E. Sauvan 5 , P. Savard 167,aw , N. Savic 115 , R. Sawada 163 , C. Sawyer 144 , L. Sawyer 95,ak , C. Sbarra 23b , A. Sbrizzi 23a , T. Scanlon 94 , J. Schaarschmidt 148 , P. Schacht 115 , B.M. Schachtner 114 , D. Schaefer 37 , L. Schaefer 137 , J. Schaeffer 99 , S. Schaepe 36 , U. Schäfer 99 , A.C. Schaffer 132 , D. Schaile 114 , R.D. Schamberger 155 , N. Scharmberg 100 , V.A. Schegelsky 138 , D. Scheirich 143 , F. Schenck 19 , M. Schernau 171 , C. Schiavi 55b,55a , S. Schier 146 , L.K. Schildgen 24 , Z.M. Schillaci 26 , E.J. Schioppa 36 , M. Schioppa 41b,41a , K.E. Schleicher 52 , S. Schlenker 36 , K.R. Schmidt-Sommerfeld 115 , K. Schmieden 36 , C. Schmitt 99 , S. Schmitt 46 , S. Schmitz 99 , ATLAS Collaboration / Physics Letters B 798 (2019) 134949 19 J.C. Schmoeckel 46 , U. Schnoor 52 , L. Schoeffel 145 , A. Schoening 61b , E. Schopf 135 , M. Schott 99 , J.F.P. Schouwenberg 119 , J. Schovancova 36 , S. Schramm 54 , F. Schroeder 182 , A. Schulte 99 , H-C. Schultz-Coulon 61a , M. Schumacher 52 , B.A. Schumm 146 , Ph. Schune 145 , A. Schwartzman 153 , T.A. Schwarz 105 , Ph. Schwemling 145 , R. Schwienhorst 106 , A. Sciandra 146 , G. Sciolla 26 , M. Scodeggio 46 , M. Scornajenghi 41b,41a , F. Scuri 71a , F. Scutti 104 , L.M. Scyboz 115 , C.D. Sebastiani 72a,72b , P. Seema 19 , S.C. Seidel 118 , A. Seiden 146 , T. Seiss 37 , J.M. Seixas 80b , G. Sekhniaidze 69a , K. Sekhon 105 , S.J. Sekula 42 , N. Semprini-Cesari 23b,23a , S. Sen 49 , S. Senkin 38 , C. Serfon 76 , L. Serin 132 , L. Serkin 66a,66b , M. Sessa 60a , H. Severini 128 , F. Sforza 170 , A. Sfyrla 54 , E. Shabalina 53 , J.D. Shahinian 146 , N.W. Shaikh 45a,45b , D. Shaked Renous 180 , L.Y. Shan 15a , R. Shang 173 , J.T. Shank 25 , M. Shapiro 18 , A. Sharma 135 , A.S. Sharma 1 , P.B. Shatalov 111 , K. Shaw 156 , S.M. Shaw 100 , A. Shcherbakova 138 , Y. Shen 128 , N. Sherafati 34 , A.D. Sherman 25 , P. Sherwood 94 , L. Shi 158,as , S. Shimizu 81 , C.O. Shimmin 183 , Y. Shimogama 179 , M. Shimojima 116 , I.P.J. Shipsey 135 , S. Shirabe 87 , M. Shiyakova 79,z , J. Shlomi 180 , A. Shmeleva 110 , M.J. Shochet 37 , S. Shojaii 104 , D.R. Shope 128 , S. Shrestha 126 , E. Shulga 180 , P. Sicho 141 , A.M. Sickles 173 , P.E. Sidebo 154 , E. Sideras Haddad 33c , O. Sidiropoulou 36 , A. Sidoti 23b,23a , F. Siegert 48 , Dj. Sijacki 16 , M. Silva Jr. 181 , M.V. Silva Oliveira 80a , S.B. Silverstein 45a , S. Simion 132 , E. Simioni 99 , R. Simoniello 99 , P. Sinervo 167 , N.B. Sinev 131 , M. Sioli 23b,23a , I. Siral 105 , S.Yu. Sivoklokov 113 , J. Sjölin 45a,45b , E. Skorda 96 , P. Skubic 128 , M. Slawinska 84 , K. Sliwa 170 , R. Slovak 143 , V. Smakhtin 180 , B.H. Smart 144 , J. Smiesko 28a , N. Smirnov 112 , S.Yu. Smirnov 112 , Y. Smirnov 112 , L.N. Smirnova 113,s , O. Smirnova 96 , J.W. Smith 53 , M. Smizanska 89 , K. Smolek 142 , A. Smykiewicz 84 , A.A. Snesarev 110 , H.L. Snoek 120 , I.M. Snyder 131 , S. Snyder 29 , R. Sobie 176,ac , A.M. Soffa 171 , A. Soffer 161 , A. Søgaard 50 , F. Sohns 53 , C.A. Solans Sanchez 36 , E.Yu. Soldatov 112 , U. Soldevila 174 , A.A. Solodkov 123 , A. Soloshenko 79 , O.V. Solovyanov 123 , V. Solovyev 138 , P. Sommer 149 , H. Son 170 , W. Song 144 , W.Y. Song 168b , A. Sopczak 142 , F. Sopkova 28b , C.L. Sotiropoulou 71a,71b , S. Sottocornola 70a,70b , R. Soualah 66a,66c,g , A.M. Soukharev 122b,122a , D. South 46 , S. Spagnolo 67a,67b , M. Spalla 115 , M. Spangenberg 178 , F. Spanò 93 , D. Sperlich 52 , T.M. Spieker 61a , R. Spighi 23b , G. Spigo 36 , M. Spina 156 , D.P. Spiteri 57 , M. Spousta 143 , A. Stabile 68a,68b , B.L. Stamas 121 , R. Stamen 61a , M. Stamenkovic 120 , E. Stanecka 84 , R.W. Stanek 6 , B. Stanislaus 135 , M.M. Stanitzki 46 , M. Stankaityte 135 , B. Stapf 120 , E.A. Starchenko 123 , G.H. Stark 146 , J. Stark 58 , S.H Stark 40 , P. Staroba 141 , P. Starovoitov 61a , S. Stärz 103 , R. Staszewski 84 , G. Stavropoulos 44 , M. Stegler 46 , P. Steinberg 29 , A.L. Steinhebel 131 , B. Stelzer 152 , H.J. Stelzer 139 , O. Stelzer-Chilton 168a , H. Stenzel 56 , T.J. Stevenson 156 , G.A. Stewart 36 , M.C. Stockton 36 , G. Stoicea 27b , M. Stolarski 140a , P. Stolte 53 , S. Stonjek 115 , A. Straessner 48 , J. Strandberg 154 , S. Strandberg 45a,45b , M. Strauss 128 , P. Strizenec 28b , R. Ströhmer 177 , D.M. Strom 131 , R. Stroynowski 42 , A. Strubig 50 , S.A. Stucci 29 , B. Stugu 17 , J. Stupak 128 , N.A. Styles 46 , D. Su 153 , S. Suchek 61a , Y. Sugaya 133 , V.V. Sulin 110 , M.J. Sullivan 90 , D.M.S. Sultan 54 , S. Sultansoy 4c , T. Sumida 85 , S. Sun 105 , X. Sun 3 , K. Suruliz 156 , C.J.E. Suster 157 , M.R. Sutton 156 , S. Suzuki 81 , M. Svatos 141 , M. Swiatlowski 37 , S.P. Swift 2 , T. Swirski 177 , A. Sydorenko 99 , I. Sykora 28a , M. Sykora 143 , T. Sykora 143 , D. Ta 99 , K. Tackmann 46,x , J. Taenzer 161 , A. Taffard 171 , R. Tafirout 168a , E. Tahirovic 92 , H. Takai 29 , R. Takashima 86 , K. Takeda 82 , T. Takeshita 150 , E.P. Takeva 50 , Y. Takubo 81 , M. Talby 101 , A.A. Talyshev 122b,122a , N.M. Tamir 161 , J. Tanaka 163 , M. Tanaka 165 , R. Tanaka 132 , B.B. Tannenwald 126 , S. Tapia Araya 173 , S. Tapprogge 99 , A. Tarek Abouelfadl Mohamed 136 , S. Tarem 160 , G. Tarna 27b,c , G.F. Tartarelli 68a , P. Tas 143 , M. Tasevsky 141 , T. Tashiro 85 , E. Tassi 41b,41a , A. Tavares Delgado 140a,140b , Y. Tayalati 35e , A.J. Taylor 50 , G.N. Taylor 104 , W. Taylor 168b , A.S. Tee 89 , R. Teixeira De Lima 153 , P. Teixeira-Dias 93 , H. Ten Kate 36 , J.J. Teoh 120 , S. Terada 81 , K. Terashi 163 , J. Terron 98 , S. Terzo 14 , M. Testa 51 , R.J. Teuscher 167,ac , S.J. Thais 183 , T. Theveneaux-Pelzer 46 , F. Thiele 40 , D.W. Thomas 93 , J.O. Thomas 42 , J.P. Thomas 21 , A.S. Thompson 57 , P.D. Thompson 21 , L.A. Thomsen 183 , E. Thomson 137 , Y. Tian 39 , R.E. Ticse Torres 53 , V.O. Tikhomirov 110,ao , Yu.A. Tikhonov 122b,122a , S. Timoshenko 112 , P. Tipton 183 , S. Tisserant 101 , K. Todome 23b,23a , S. Todorova-Nova 5 , S. Todt 48 , J. Tojo 87 , S. Tokár 28a , K. Tokushuku 81 , E. Tolley 126 , K.G. Tomiwa 33c , M. Tomoto 117 , L. Tompkins 153,p , K. Toms 118 , B. Tong 59 , P. Tornambe 102 , E. Torrence 131 , H. Torres 48 , E. Torró Pastor 148 , C. Tosciri 135 , J. Toth 101,aa , D.R. Tovey 149 , C.J. Treado 124 , T. Trefzger 177 , F. Tresoldi 156 , A. Tricoli 29 , I.M. Trigger 168a , S. Trincaz-Duvoid 136 , W. Trischuk 167 , B. Trocmé 58 , A. Trofymov 132 , C. Troncon 68a , M. Trovatelli 176 , F. Trovato 156 , L. Truong 33b , M. Trzebinski 84 , A. Trzupek 84 , F. Tsai 46 , J.C-L. Tseng 135 , P.V. Tsiareshka 107,ai , A. Tsirigotis 162 , N. Tsirintanis 9 , V. Tsiskaridze 155 , E.G. Tskhadadze 159a , M. Tsopoulou 162 , 20 ATLAS Collaboration / Physics Letters B 798 (2019) 134949 I.I. Tsukerman 111 , V. Tsulaia 18 , S. Tsuno 81 , D. Tsybychev 155 , Y. Tu 63b , A. Tudorache 27b , V. Tudorache 27b , T.T. Tulbure 27a , A.N. Tuna 59 , S. Turchikhin 79 , D. Turgeman 180 , I. Turk Cakir 4b,t , R.J. Turner 21 , R.T. Turra 68a , P.M. Tuts 39 , S Tzamarias 162 , E. Tzovara 99 , G. Ucchielli 47 , K. Uchida 163 , I. Ueda 81 , M. Ughetto 45a,45b , F. Ukegawa 169 , G. Unal 36 , A. Undrus 29 , G. Unel 171 , F.C. Ungaro 104 , Y. Unno 81 , K. Uno 163 , J. Urban 28b , P. Urquijo 104 , G. Usai 8 , J. Usui 81 , L. Vacavant 101 , V. Vacek 142 , B. Vachon 103 , K.O.H. Vadla 134 , A. Vaidya 94 , C. Valderanis 114 , E. Valdes Santurio 45a,45b , M. Valente 54 , S. Valentinetti 23b,23a , A. Valero 174 , L. Valéry 46 , R.A. Vallance 21 , A. Vallier 36 , J.A. Valls Ferrer 174 , T.R. Van Daalen 14 , P. Van Gemmeren 6 , I. Van Vulpen 120 , M. Vanadia 73a,73b , W. Vandelli 36 , A. Vaniachine 166 , D. Vannicola 72a,72b , R. Vari 72a , E.W. Varnes 7 , C. Varni 55b,55a , T. Varol 42 , D. Varouchas 132 , K.E. Varvell 157 , M.E. Vasile 27b , G.A. Vasquez 176 , J.G. Vasquez 183 , F. Vazeille 38 , D. Vazquez Furelos 14 , T. Vazquez Schroeder 36 , J. Veatch 53 , V. Vecchio 74a,74b , M.J. Veen 120 , L.M. Veloce 167 , F. Veloso 140a,140c , S. Veneziano 72a , A. Ventura 67a,67b , N. Venturi 36 , A. Verbytskyi 115 , V. Vercesi 70a , M. Verducci 74a,74b , C.M. Vergel Infante 78 , C. Vergis 24 , W. Verkerke 120 , A.T. Vermeulen 120 , J.C. Vermeulen 120 , M.C. Vetterli 152,aw , N. Viaux Maira 147b , M. Vicente Barreto Pinto 54 , T. Vickey 149 , O.E. Vickey Boeriu 149 , G.H.A. Viehhauser 135 , L. Vigani 135 , M. Villa 23b,23a , M. Villaplana Perez 68a,68b , E. Vilucchi 51 , M.G. Vincter 34 , V.B. Vinogradov 79 , A. Vishwakarma 46 , C. Vittori 23b,23a , I. Vivarelli 156 , M. Vogel 182 , P. Vokac 142 , S.E. von Buddenbrock 33c , E. Von Toerne 24 , V. Vorobel 143 , K. Vorobev 112 , M. Vos 174 , J.H. Vossebeld 90 , N. Vranjes 16 , M. Vranjes Milosavljevic 16 , V. Vrba 142 , M. Vreeswijk 120 , T. Šfiligoj 91 , R. Vuillermet 36 , I. Vukotic 37 , T. Ženiš 28a , L. Živković 16 , P. Wagner 24 , W. Wagner 182 , J. Wagner-Kuhr 114 , H. Wahlberg 88 , K. Wakamiya 82 , V.M. Walbrecht 115 , J. Walder 89 , R. Walker 114 , S.D. Walker 93 , W. Walkowiak 151 , V. Wallangen 45a,45b , A.M. Wang 59 , C. Wang 60b , F. Wang 181 , H. Wang 18 , H. Wang 3 , J. Wang 157 , J. Wang 61b , P. Wang 42 , Q. Wang 128 , R.-J. Wang 99 , R. Wang 60a , R. Wang 6 , S.M. Wang 158 , W.T. Wang 60a , W. Wang 15c,ad , W.X. Wang 60a,ad , Y. Wang 60a,al , Z. Wang 60c , C. Wanotayaroj 46 , A. Warburton 103 , C.P. Ward 32 , D.R. Wardrope 94 , N. Warrack 57 , A. Washbrook 50 , A.T. Watson 21 , M.F. Watson 21 , G. Watts 148 , B.M. Waugh 94 , A.F. Webb 11 , S. Webb 99 , C. Weber 183 , M.S. Weber 20 , S.A. Weber 34 , S.M. Weber 61a , A.R. Weidberg 135 , J. Weingarten 47 , M. Weirich 99 , C. Weiser 52 , P.S. Wells 36 , T. Wenaus 29 , T. Wengler 36 , S. Wenig 36 , N. Wermes 24 , M.D. Werner 78 , P. Werner 36 , M. Wessels 61a , T.D. Weston 20 , K. Whalen 131 , N.L. Whallon 148 , A.M. Wharton 89 , A.S. White 105 , A. White 8 , M.J. White 1 , D. Whiteson 171 , B.W. Whitmore 89 , F.J. Wickens 144 , W. Wiedenmann 181 , M. Wielers 144 , N. Wieseotte 99 , C. Wiglesworth 40 , L.A.M. Wiik-Fuchs 52 , F. Wilk 100 , H.G. Wilkens 36 , L.J. Wilkins 93 , H.H. Williams 137 , S. Williams 32 , C. Willis 106 , S. Willocq 102 , J.A. Wilson 21 , I. Wingerter-Seez 5 , E. Winkels 156 , F. Winklmeier 131 , O.J. Winston 156 , B.T. Winter 52 , M. Wittgen 153 , M. Wobisch 95 , A. Wolf 99 , T.M.H. Wolf 120 , R. Wolff 101 , R.W. Wölker 135 , J. Wollrath 52 , M.W. Wolter 84 , H. Wolters 140a,140c , V.W.S. Wong 175 , N.L. Woods 146 , S.D. Worm 21 , B.K. Wosiek 84 , K.W. Woźniak 84 , K. Wraight 57 , S.L. Wu 181 , X. Wu 54 , Y. Wu 60a , T.R. Wyatt 100 , B.M. Wynne 50 , S. Xella 40 , Z. Xi 105 , L. Xia 178 , D. Xu 15a , H. Xu 60a,c , L. Xu 29 , T. Xu 145 , W. Xu 105 , Z. Xu 60b , Z. Xu 153 , B. Yabsley 157 , S. Yacoob 33a , K. Yajima 133 , D.P. Yallup 94 , D. Yamaguchi 165 , Y. Yamaguchi 165 , A. Yamamoto 81 , T. Yamanaka 163 , F. Yamane 82 , M. Yamatani 163 , T. Yamazaki 163 , Y. Yamazaki 82 , Z. Yan 25 , H.J. Yang 60c,60d , H.T. Yang 18 , S. Yang 77 , X. Yang 60b,58 , Y. Yang 163 , Z. Yang 17 , W-M. Yao 18 , Y.C. Yap 46 , Y. Yasu 81 , E. Yatsenko 60c,60d , J. Ye 42 , S. Ye 29 , I. Yeletskikh 79 , M.R. Yexley 89 , E. Yigitbasi 25 , E. Yildirim 99 , K. Yorita 179 , K. Yoshihara 137 , C.J.S. Young 36 , C. Young 153 , J. Yu 78 , R. Yuan 60b , X. Yue 61a , S.P.Y. Yuen 24 , B. Zabinski 84 , G. Zacharis 10 , E. Zaffaroni 54 , J. Zahreddine 136 , R. Zaidan 14 , A.M. Zaitsev 123,an , T. Zakareishvili 159b , N. Zakharchuk 34 , S. Zambito 59 , D. Zanzi 36 , D.R. Zaripovas 57 , S.V. Zeißner 47 , C. Zeitnitz 182 , G. Zemaityte 135 , J.C. Zeng 173 , O. Zenin 123 , D. Zerwas 132 , M. Zgubič 135 , D.F. Zhang 15b , F. Zhang 181 , G. Zhang 60a , G. Zhang 15b , H. Zhang 15c , J. Zhang 6 , L. Zhang 15c , L. Zhang 60a , M. Zhang 173 , R. Zhang 60a , R. Zhang 24 , X. Zhang 60b , Y. Zhang 15a,15d , Z. Zhang 63a , Z. Zhang 132 , P. Zhao 49 , Y. Zhao 60b , Z. Zhao 60a , A. Zhemchugov 79 , Z. Zheng 105 , D. Zhong 173 , B. Zhou 105 , C. Zhou 181 , M.S. Zhou 15a,15d , M. Zhou 155 , N. Zhou 60c , Y. Zhou 7 , C.G. Zhu 60b , H.L. Zhu 60a , H. Zhu 15a , J. Zhu 105 , Y. Zhu 60a , X. Zhuang 15a , K. Zhukov 110 , V. Zhulanov 122b,122a , D. Zieminska 65 , N.I. Zimine 79 , S. Zimmermann 52 , Z. Zinonos 115 , M. Ziolkowski 151 , G. Zobernig 181 , A. Zoccoli 23b,23a , K. Zoch 53 , T.G. Zorbas 149 , R. Zou 37 , L. Zwalinski 36 1 Department of Physics, University of Adelaide, Adelaide, Australia ATLAS Collaboration / Physics Letters B 798 (2019) 134949 21 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 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 National Centre for Scientific Research “Demokritos”, Agia Paraskevi, Greece 45 (a) Department of Physics, Stockholm University; (b) Oskar Klein Centre, Stockholm, Sweden 46 Deutsches Elektronen-Synchrotron DESY, Hamburg and Zeuthen, Germany 47 Lehrstuhl für Experimentelle Physik IV, Technische Universität Dortmund, Dortmund, Germany 48 Institut für Kern- und Teilchenphysik, Technische Universität Dresden, Dresden, Germany 49 Department of Physics, Duke University, Durham NC, United States of America 50 SUPA - School of Physics and Astronomy, University of Edinburgh, Edinburgh, United Kingdom 51 INFN e Laboratori Nazionali di Frascati, Frascati, Italy 52 Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany 53 II. Physikalisches Institut, Georg-August-Universität Göttingen, Göttingen, Germany 54 Département de Physique Nucléaire et Corpusculaire, Université de Genève, Genève, Switzerland 55 (a) Dipartimento di Fisica, Università di Genova, Genova; (b) INFN Sezione di Genova, Italy 56 II. Physikalisches Institut, Justus-Liebig-Universität Giessen, Giessen, Germany 57 SUPA - School of Physics and Astronomy, University of Glasgow, Glasgow, United Kingdom 58 LPSC, Université Grenoble Alpes, CNRS/IN2P3, Grenoble INP, Grenoble, France 59 Laboratory for Particle Physics and Cosmology, Harvard University, Cambridge MA, United States of America 60 (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 61 (a) Kirchhoff-Institut für Physik, Ruprecht-Karls-Universität Heidelberg, Heidelberg; (b) Physikalisches Institut, Ruprecht-Karls-Universität Heidelberg, Heidelberg, Germany 62 Faculty of Applied Information Science, Hiroshima Institute of Technology, Hiroshima, Japan 63 (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 64 Department of Physics, National Tsing Hua University, Hsinchu, Taiwan 65 Department of Physics, Indiana University, Bloomington IN, United States of America 66 (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 67 (a) INFN Sezione di Lecce; (b) Dipartimento di Matematica e Fisica, Università del Salento, Lecce, Italy 68 (a) INFN Sezione di Milano; (b) Dipartimento di Fisica, Università di Milano, Milano, Italy 69 (a) INFN Sezione di Napoli; (b) Dipartimento di Fisica, Università di Napoli, Napoli, Italy 22 ATLAS Collaboration / Physics Letters B 798 (2019) 134949 70 (a) INFN Sezione di Pavia; (b) Dipartimento di Fisica, Università di Pavia, Pavia, Italy 71 (a) INFN Sezione di Pisa; (b) Dipartimento di Fisica E. Fermi, Università di Pisa, Pisa, Italy 72 (a) INFN Sezione di Roma; (b) Dipartimento di Fisica, Sapienza Università di Roma, Roma, Italy 73 (a) INFN Sezione di Roma Tor Vergata; (b) Dipartimento di Fisica, Università di Roma Tor Vergata, Roma, Italy 74 (a) INFN Sezione di Roma Tre; (b) Dipartimento di Matematica e Fisica, Università Roma Tre, Roma, Italy 75 (a) INFN-TIFPA; (b) Università degli Studi di Trento, Trento, Italy 76 Institut für Astro- und Teilchenphysik, Leopold-Franzens-Universität, Innsbruck, Austria 77 University of Iowa, Iowa City IA, United States of America 78 Department of Physics and Astronomy, Iowa State University, Ames IA, United States of America 79 Joint Institute for Nuclear Research, Dubna, Russia 80 (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 81 KEK, High Energy Accelerator Research Organization, Tsukuba, Japan 82 Graduate School of Science, Kobe University, Kobe, Japan 83 (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 84 Institute of Nuclear Physics Polish Academy of Sciences, Krakow, Poland 85 Faculty of Science, Kyoto University, Kyoto, Japan 86 Kyoto University of Education, Kyoto, Japan 87 Research Center for Advanced Particle Physics and Department of Physics, Kyushu University, Fukuoka , Japan 88 Instituto de Física La Plata, Universidad Nacional de La Plata and CONICET, La Plata, Argentina 89 Physics Department, Lancaster University, Lancaster, United Kingdom 90 Oliver Lodge Laboratory, University of Liverpool, Liverpool, United Kingdom 91 Department of Experimental Particle Physics, Jožef Stefan Institute and Department of Physics, University of Ljubljana, Ljubljana, Slovenia 92 School of Physics and Astronomy, Queen Mary University of London, London, United Kingdom 93 Department of Physics, Royal Holloway University of London, Egham, United Kingdom 94 Department of Physics and Astronomy, University College London, London, United Kingdom 95 Louisiana Tech University, Ruston LA, United States of America 96 Fysiska institutionen, Lunds universitet, Lund, Sweden 97 Centre de Calcul de l’Institut National de Physique Nucléaire et de Physique des Particules (IN2P3), Villeurbanne, France 98 Departamento de Física Teorica C-15 and CIAFF, Universidad Autónoma de Madrid, Madrid, Spain 99 Institut für Physik, Universität Mainz, Mainz, Germany 100 School of Physics and Astronomy, University of Manchester, Manchester, United Kingdom 101 CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille, France 102 Department of Physics, University of Massachusetts, Amherst MA, United States of America 103 Department of Physics, McGill University, Montreal QC, Canada 104 School of Physics, University of Melbourne, Victoria, Australia 105 Department of Physics, University of Michigan, Ann Arbor MI, United States of America 106 Department of Physics and Astronomy, Michigan State University, East Lansing MI, United States of America 107 B.I. Stepanov Institute of Physics, National Academy of Sciences of Belarus, Minsk, Belarus 108 Research Institute for Nuclear Problems of Byelorussian State University, Minsk, Belarus 109 Group of Particle Physics, University of Montreal, Montreal QC, Canada 110 P.N. Lebedev Physical Institute of the Russian Academy of Sciences, Moscow, Russia 111 Institute for Theoretical and Experimental Physics of the National Research Centre Kurchatov Institute, Moscow, Russia 112 National Research Nuclear University MEPhI, Moscow, Russia 113 D.V. Skobeltsyn Institute of Nuclear Physics, M.V. Lomonosov Moscow State University, Moscow, Russia 114 Fakultät für Physik, Ludwig-Maximilians-Universität München, München, Germany 115 Max-Planck-Institut für Physik (Werner-Heisenberg-Institut), München, Germany 116 Nagasaki Institute of Applied Science, Nagasaki, Japan 117 Graduate School of Science and Kobayashi-Maskawa Institute, Nagoya University, Nagoya, Japan 118 Department of Physics and Astronomy, University of New Mexico, Albuquerque NM, United States of America 119 Institute for Mathematics, Astrophysics and Particle Physics, Radboud University Nijmegen/Nikhef, Nijmegen, Netherlands 120 Nikhef National Institute for Subatomic Physics and University of Amsterdam, Amsterdam, Netherlands 121 Department of Physics, Northern Illinois University, DeKalb IL, United States of America 122 (a) Budker Institute of Nuclear Physics and NSU, SB RAS, Novosibirsk; (b) Novosibirsk State University Novosibirsk, Russia 123 Institute for High Energy Physics of the National Research Centre Kurchatov Institute, Protvino, Russia 124 Department of Physics, New York University, New York NY, United States of America 125 Ochanomizu University, Otsuka, Bunkyo-ku, Tokyo, Japan 126 Ohio State University, Columbus OH, United States of America 127 Faculty of Science, Okayama University, Okayama, Japan 128 Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, Norman OK, United States of America 129 Department of Physics, Oklahoma State University, Stillwater OK, United States of America 130 Palacký University, RCPTM, Joint Laboratory of Optics, Olomouc, Czech Republic 131 Center for High Energy Physics, University of Oregon, Eugene OR, United States of America 132 LAL, Université Paris-Sud, CNRS/IN2P3, Université Paris-Saclay, Orsay, France 133 Graduate School of Science, Osaka University, Osaka, Japan 134 Department of Physics, University of Oslo, Oslo, Norway 135 Department of Physics, Oxford University, Oxford, United Kingdom 136 LPNHE, Sorbonne Université, Paris Diderot Sorbonne Paris Cité, CNRS/IN2P3, Paris, France 137 Department of Physics, University of Pennsylvania, Philadelphia PA, United States of America 138 Konstantinov Nuclear Physics Institute of National Research Centre “Kurchatov Institute”, PNPI, St. Petersburg, Russia 139 Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh PA, United States of America 140 (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 141 Institute of Physics of the Czech Academy of Sciences, Prague, Czech Republic 142 Czech Technical University in Prague, Prague, Czech Republic 143 Charles University, Faculty of Mathematics and Physics, Prague, Czech Republic 144 Particle Physics Department, Rutherford Appleton Laboratory, Didcot, United Kingdom ATLAS Collaboration / Physics Letters B 798 (2019) 134949 23 145 IRFU, CEA, Université Paris-Saclay, Gif-sur-Yvette, France 146 Santa Cruz Institute for Particle Physics, University of California Santa Cruz, Santa Cruz CA, United States of America 147 (a) Departamento de Física, Pontificia Universidad Católica de Chile, Santiago; (b) Departamento de Física, Universidad Técnica Federico Santa María, Valparaíso, Chile 148 Department of Physics, University of Washington, Seattle WA, United States of America 149 Department of Physics and Astronomy, University of Sheffield, Sheffield, United Kingdom 150 Department of Physics, Shinshu University, Nagano, Japan 151 Department Physik, Universität Siegen, Siegen, Germany 152 Department of Physics, Simon Fraser University, Burnaby BC, Canada 153 SLAC National Accelerator Laboratory, Stanford CA, United States of America 154 Physics Department, Royal Institute of Technology, Stockholm, Sweden 155 Departments of Physics and Astronomy, Stony Brook University, Stony Brook NY, United States of America 156 Department of Physics and Astronomy, University of Sussex, Brighton, United Kingdom 157 School of Physics, University of Sydney, Sydney, Australia 158 Institute of Physics, Academia Sinica, Taipei, Taiwan 159 (a) E. Andronikashvili Institute of Physics, Iv. Javakhishvili Tbilisi State University, Tbilisi; (b) High Energy Physics Institute, Tbilisi State University, Tbilisi, Georgia 160 Department of Physics, Technion, Israel Institute of Technology, Haifa, Israel 161 Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Tel Aviv, Israel 162 Department of Physics, Aristotle University of Thessaloniki, Thessaloniki, Greece 163 International Center for Elementary Particle Physics and Department of Physics, University of Tokyo, Tokyo, Japan 164 Graduate School of Science and Technology, Tokyo Metropolitan University, Tokyo, Japan 165 Department of Physics, Tokyo Institute of Technology, Tokyo, Japan 166 Tomsk State University, Tomsk, Russia 167 Department of Physics, University of Toronto, Toronto ON, Canada 168 (a) TRIUMF, Vancouver BC; (b) Department of Physics and Astronomy, York University, Toronto ON, Canada 169 Division of Physics and Tomonaga Center for the History of the Universe, Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Japan 170 Department of Physics and Astronomy, Tufts University, Medford MA, United States of America 171 Department of Physics and Astronomy, University of California Irvine, Irvine CA, United States of America 172 Department of Physics and Astronomy, University of Uppsala, Uppsala, Sweden 173 Department of Physics, University of Illinois, Urbana IL, United States of America 174 Instituto de Física Corpuscular (IFIC), Centro Mixto Universidad de Valencia - CSIC, Valencia, Spain 175 Department of Physics, University of British Columbia, Vancouver BC, Canada 176 Department of Physics and Astronomy, University of Victoria, Victoria BC, Canada 177 Fakultät für Physik und Astronomie, Julius-Maximilians-Universität Würzburg, Würzburg, Germany 178 Department of Physics, University of Warwick, Coventry, United Kingdom 179 Waseda University, Tokyo, Japan 180 Department of Particle Physics, Weizmann Institute of Science, Rehovot, Israel 181 Department of Physics, University of Wisconsin, Madison WI, United States of America 182 Fakultät für Mathematik und Naturwissenschaften, Fachgruppe Physik, Bergische Universität Wuppertal, Wuppertal, Germany 183 Department of Physics, Yale University, New Haven CT, United States of America 184 Yerevan Physics Institute, Yerevan, Armenia a Also at Centre for High Performance Computing, CSIR Campus, Rosebank, Cape Town; South Africa. b Also at CERN, Geneva; Switzerland. c Also at CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille; France. d Also at Département de Physique Nucléaire et Corpusculaire, Université de Genève, Genève; Switzerland. e Also at Departament de Fisica de la Universitat Autonoma de Barcelona, Barcelona; Spain. f Also at Departamento de Física, Instituto Superior Técnico, Universidade de Lisboa, Lisboa; Portugal. g Also at Department of Applied Physics and Astronomy, University of Sharjah, Sharjah; United 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, Stanford University, Stanford CA; United States of America. q Also at Department of Physics, University of Fribourg, Fribourg; Switzerland. r Also at Department of Physics, University of Michigan, Ann Arbor MI; United States of America. s Also at Faculty of Physics, M.V. Lomonosov Moscow State University, Moscow; Russia. t Also at Giresun University, Faculty of Engineering, Giresun; Turkey. u Also at Graduate School of Science, Osaka University, Osaka; Japan. v Also at Hellenic Open University, Patras; Greece. w Also at Institucio Catalana de Recerca i Estudis Avancats, ICREA, Barcelona; Spain. x Also at Institut für Experimentalphysik, Universität Hamburg, Hamburg; Germany. y Also at Institute for Mathematics, Astrophysics and Particle Physics, Radboud University Nijmegen/Nikhef, Nijmegen; Netherlands. z Also at Institute for Nuclear Research and Nuclear Energy (INRNE) of the Bulgarian Academy of Sciences, Sofia; Bulgaria. aa Also at Institute for Particle and Nuclear Physics, Wigner Research Centre for Physics, Budapest; Hungary. ab Also at Institute of High Energy Physics, Chinese Academy of Sciences, Beijing; China. ac Also at Institute of Particle Physics (IPP); Canada. ad Also at Institute of Physics, Academia Sinica, Taipei; Taiwan. ae Also at Institute of Physics, Azerbaijan Academy of Sciences, Baku; Azerbaijan. af Also at Institute of Theoretical Physics, Ilia State University, Tbilisi; Georgia. ag Also at Instituto de Fisica Teorica, IFT-UAM/CSIC, Madrid; Spain. ah Also at Istanbul University, Dept. of Physics, Istanbul; Turkey. ai Also at Joint Institute for Nuclear Research, Dubna; Russia. 24 ATLAS Collaboration / Physics Letters B 798 (2019) 134949 aj Also at LAL, Université Paris-Sud, CNRS/IN2P3, Université Paris-Saclay, Orsay; France. ak Also at Louisiana Tech University, Ruston LA; United States of America. al Also at LPNHE, Sorbonne Université, Paris Diderot Sorbonne Paris Cité, CNRS/IN2P3, Paris; France. am Also at Manhattan College, New York NY; United States of America. an Also at Moscow Institute of Physics and Technology State University, Dolgoprudny; Russia. ao Also at National Research Nuclear University MEPhI, Moscow; Russia. ap Also at Physics Department, An-Najah National University, Nablus; Palestine. aq Also at Physics Dept, University of South Africa, Pretoria; South Africa. ar Also at Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, Freiburg; Germany. as Also at School of Physics, Sun Yat-sen University, Guangzhou; China. at Also at The City College of New York, New York NY; United States of America. au Also at The Collaborative Innovation Center of Quantum Matter (CICQM), Beijing; China. av Also at Tomsk State University, Tomsk, and Moscow Institute of Physics and Technology State University, Dolgoprudny; Russia. aw Also at TRIUMF, Vancouver BC; Canada. ax Also at Universita di Napoli Parthenope, Napoli; Italy. ∗ Deceased.