PHYSICAL REVIEW LETTERS 122, 231801 (2019) Combination of Searches for Invisible Higgs Boson Decays with the ATLAS Experiment M. Aaboud et al.* (ATLAS Collaboration) (Received 11 April 2019; published 13 June 2019) Dark matter particles, if sufficiently light, may be produced in decays of the Higgs boson. This Letter presents a statistical combination of searches for H → invisible decays where H is produced according to the standard model via vector boson fusion, ZðllÞH, and W=ZðhadÞH, all performed with the ATLAS pffiffiffi detector using 36.1 fb−1 of pp collisions at a center-of-mass energy of s ¼ 13 TeV at the LHC. In pffiffiffi combination with the results at s ¼ 7 and 8 TeV, an exclusion limit on the H → invisible branching ratio of 0.26ð0.17þ0.07 −0.05 Þ at 95% confidence level is observed (expected). DOI: 10.1103/PhysRevLett.122.231801 One of the central open questions in physics today is the (VðhadÞH) [35]. These searches for invisible Higgs boson nature of dark matter (DM) that is found to comprise most decays have been statistically combined, and an upper of the matter in the Universe [1–4]. A compelling candidate limit at 95% confidence level (C.L.) on the invisible Higgs for DM is a stable electrically neutral particle χ whose boson branching ratio of BH→inv < 0.25ð0.27þ0.10 −0.08 Þ [36] nongravitational interactions with Standard Model (SM) was observed (expected). In combination with visible particles are weak. Such a particle with a mass comparable decay modes of the Higgs boson, the upper observed to the mass scale of the electroweak sector particles could (expected) limit improved to 0.23 (0.24) [36]. Direct be detectable [5–7] and accommodate the observed DM searches for invisible Higgs decays were performed using pffiffiffi relic density [8,9]. Numerous models predict detectable up to 36.1 fb−1 of pp collision data at s ¼ 13 TeV production rates of such DM particles at the Large Hadron recorded in 2015 and 2016 in the VBF [37], ZðlepÞH [38], Collider (LHC) [10–12]. In a wide class of those models, and VðhadÞH [39] pffiffiffi topologies at ATLAS. The aforemen- the 125 GeV Higgs boson H [13,14] acts as a portal tioned results at s ¼ 13 TeV will be referred to as “Run 2 between a dark sector and the SM sector, either through results” in the following. Similar searches were performed Yukawa-type couplings to fermionic dark matter, or by the CMS Collaboration [40–44]. other mechanisms [15–28]. If kinematically allowed, This Letter presents the statistical combination of the decays of the Higgs boson to DM particles represent a Run 2 searches with 36.1 fb−1 of data for invisible distinct signature in such models. Higgs boson decays to decays of the Higgs boson using the ATLAS detector. DM particles can only be indirectly inferred through Subsequently, a statistical combination with the combined missing transverse momentum [29] Emiss T due to DM Run 1 result [36] from ATLAS is performed. An overview particles escaping detection, and are therefore termed of all results used as inputs in this combination is given in “invisible” (inv). Table I. The analysis is performed under the assumption of Direct searches for invisible Higgs boson decays have SM Higgs boson production. Visible decay modes of the been carried out with the ATLAS detector [30–32] in Run 1 Higgs boson are not considered. of the LHC, using up to 4.7 fb−1 of pp collision data at a A brief overview of the Run 2 searches for H → inv is pffiffiffi center-of-mass energy of s ¼ 7 TeV and up to 20.3 fb−1 given below. at 8 TeV. Different event topologies were considered, VBF topology [37].—The analysis of the VBF produc- assuming SM production rates: vector boson fusion tion mode employs an Emiss T trigger that is 98% efficient or (VBF) [33], Higgsstrahlung from a Z boson decaying into better in the considered region of phase space. The event a pair of electrons or muons (ZðlepÞH) [34], and selection requires EmissT > 180 GeV. Jets (j) are recon- Higgsstrahlung from a W or Z boson decaying into hadrons structed up to jηðjÞj < 4.5 from energy clusters in the calorimeter using the anti-kt algorithm [45] with a radius * Full author list given at the end of the Letter. parameter R ¼ 0.4. The two jets leading in pT are required to be separated by jΔηjj j > 4.8. There should be no Published by the American Physical Society under the terms of additional jets with pT > 25 GeV and no isolated electron the Creative Commons Attribution 4.0 International license. or muon candidate with pT > 7 GeV. These requirements Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, serve to reduce the contribution from W=Z production in and DOI. Funded by SCOAP3. association with jets (V þ jets). In the search signal region 0031-9007=19=122(23)=231801(20) 231801-1 © 2019 CERN, for the ATLAS Collaboration PHYSICAL REVIEW LETTERS 122, 231801 (2019) TABLE I. Observed and expected upper limits on BH→inv at 95% C.L. from direct searches for invisible decays of the 125 GeV Higgs boson and statistical combinations. Also given are the observed p values under the SM hypothesis. pffiffiffi Analysis s Int. luminosity Observed Expected pSM value Reference −1 Run 2 VBF 13 TeV 36.1 fb 0.37 0.28þ0.11 −0.08 0.19 [37] Run 2 ZðlepÞH 13 TeV 36.1 fb−1 0.67 0.39þ0.17 −0.11 0.06 [38] Run 2 VðhadÞH 13 TeV 36.1 fb−1 0.83 0.58þ0.23 −0.16 0.12 [39] Run 2 Comb. 13 TeV 36.1 fb−1 0.38 0.21þ0.08 −0.06 0.03 this Letter Run 1 Comb. 7,8 TeV 4.7, 20.3 fb−1 0.25 0.27þ0.10 −0.08  [36] Run 1 þ 2 Comb. 7,8,13 TeV 4.7, 20.3, 36.1 fb−1 0.26 0.17þ0.07 −0.05 0.10 this Letter (SR) the mjj distribution of the background falls more decays into hadrons. The final state signature of large Emiss T rapidly than the signal, where mjj represents the invariant and jets also receives contributions from Higgs boson mass of the two selected leading jets. Thus the SR is production via gluon fusion with jets originating from divided into three mjj regions (1 < mjj =TeV < 1.5, initial state radiation, and production via the VBF process. 1.5 < mjj =TeV < 2, and mjj =TeV > 2) to improve the Selected events must pass a Emiss T trigger and must not search sensitivity. The dominant background sources are contain an isolated electron or muon with pT > 7 GeV. ZðννÞ þ jets and WðlνÞ þ jets production, where the As a V is boosted, the two jets from its decay become charged lepton l is not detected. Control regions (CR) increasingly collimated and are eventually merged into one enriched in ZðllÞ þ jets and WðlνÞ þ jets processes with single reconstructed jet. Thus, this search is conducted in l ¼ e, μ are defined to determine the respective normali- two topological channels. In the “merged” topology, the SR zation factors in the SR. The main contributions to is defined with Emiss T > 250 GeV and has at least one uncertainties are from the finite number of simulated trimmed [48,49] large-R jet (J) that is reconstructed using Monte Carlo (MC) events, the modeling of V þ jets the anti-kt algorithm with R ¼ 1.0. The signal large-R jet production, and accuracy of the jet energy scale (JES). is the one with the highest pT . For the “resolved” topology, The final discriminant is the number of events in the three the selected event should have Emiss T > 150 GeV and at mjj regions. least two small-R jets (j) with R ¼ 0.4. Each event is first ZðlepÞH topology [38].—This search is conducted in the passed through the merged topology selection and, if it Higgsstrahlung channel where the Z boson decays into a fails, it is passed through the resolved topology selection. pair of electrons or muons. A selected candidate event must To improve the search sensitivity, the selected events are pass at least one of the various single-lepton triggers, fulfill further split into categories with zero, one, and two Emiss T > 90 GeV and Emiss T =H T > 0.6, where H T is calcu- identified b-jets, and into two mass regions of the invariant lated as the scalar sum of the pT of the selected leptons and mass of the signal large-R jet (two signal small-R jets) for jets, and have exactly one pair of isolated electrons or the merged (resolved) topology. The low mass region muons with an invariant mass that is consistent with that of (70 ≲ mJ , mjj =GeV ≲ 100) targets the hadronic W=Z the Z boson. The transverse momentum requirement on the boson decays of the associated production, whereas the leading (subleading) charged lepton is pT > 30 ð20Þ GeV. high mass region (100 ≲ mJ , mjj =GeV < 250) is sensitive To reduce the Z þ jets background, the dilepton system to gluon fusion and VBF production. The main background must be aligned back to back relative to the Emiss T vector in contributions are from the V þ jets and tt̄ processes. The the transverse plane. Events with jets originating from b- predictions from MC simulations are constrained with CRs quarks (b-jets) are vetoed to suppress backgrounds from that contained one or two leptons, and are kinematically top quark pair (tt̄) production and W boson production in similar to the SR. The final discriminant is EmissT . association with a single top quark (Wt). The irreducible The SRs and CRs of the individual input analyses are ZðννÞZðllÞ background is estimated from MC simulations either orthogonal by construction, or were shown to have an and its production yield is normalized to the theoretical overlap below 1%, which is neglected in the following. prediction of Refs. [46,47]. The WðlνÞZðllÞ background The statistical combination of the analyses is performed contribution is also predicted with MC simulations and is by constructing the product of their likelihoods and normalized by a scale factor that is obtained from a CR maximizing the resulting likelihood ratio ΛðBH→inv ; θÞ enriched in WZ events. The Z þ jets background is [50]. This is done following the implementation described estimated with a data-driven method that uses Z-enriched in Ref. [51,52], with BH→inv as the parameter of CRs. The final discriminant is EmissT . interest. Systematic uncertainties are modeled in the like- VðhadÞH topology [39].—This analysis considers the lihood function as nuisance parameters θ constrained by Higgsstrahlung channel where the associated W or Z boson Gaussian or log-normal probability density functions [36]. 231801-2 PHYSICAL REVIEW LETTERS 122, 231801 (2019) 14 14 Expected results are obtained using the Asimov dataset ATLAS -1 ATLAS 12 s = 13 TeV, 36.1 fb 12 s = 7 TeV, 4.7 fb-1 technique [50]. V(had)H s = 8 TeV, 20.3 fb-1 s = 13 TeV, 36.1 fb-1 10 Z(lep)H 10 In the combination of Run 2 results, most experimental VBF Combined Run 1 combined Run 2 combined systematic uncertainties as well as the uncertainty on the Run 1+2 combined -2 Δln(Λ) -2 Δln(Λ) 8 8 integrated luminosity and the modeling of additional pp 6 6 collisions in the same and neighboring bunch crossings 4 2σ 4 2σ (pileup) are correlated across all search channels. Some 2 2 1σ 1σ experimental uncertainties related to flavor tagging and the JES are represented through different parametrizations in −0.2 0 0.2 0.4 0.6 −0.2 0 0.2 0.4 0.6 BH→ inv BH→ inv the input analyses and are therefore treated as uncorrelated. The impact of this assumption on the combined result is FIG. 1. The observed negative logarithmic profile likelihood estimated using alternative correlation models where the ratios −2Δ lnðΛÞ as a function of BH→inv of the VðhadÞH, leading sources of systematic uncertainty in the respective ZðlepÞH, and VBF topologies using Run 2 data only and their parametrizations are treated as correlated, and found to statistical combination (left). The −2Δ lnðΛÞ functions for the have an absolute effect on the BH→inv limit of the order of Run 2 combination together with the Run 1 combination and the 0.01. The systematic uncertainties on the total H → inv total Run 1 þ 2 combination (right). signal cross section due to the choice of parton distribution functions (PDF) are considered correlated among all channels. By contrast, uncertainties due to missing higher flavor and pileup are taken as either correlated or uncorre- order corrections are estimated through variations of lated between the runs, and the choice which results in a factorization and renormalization scales and treated as weaker expected exclusion limit on BH→inv is adopted. The correlated between the ZðlepÞH and VðhadÞH processes. uncertainty on the JES of b-quark jets was estimated using This is not done for VBF, which represents a distinct MC simulations [54,55] and is therefore considered corre- topology. The impact of the corresponding uncertainties lated. For the signal modeling, the parton shower uncer- on the acceptance rather than the total cross section of tainty in the VðhadÞH channel, the uncertainty from VðhadÞH production is evaluated and found negligible. missing higher order corrections in the ZðlepÞH analysis, Few systematic uncertainties that are tightly constrained in and the uncertainty on the jet multiplicity in the VBF a given analysis are left uncorrelated in order not to channel [56] are each taken as correlated between the runs introduce any potential phase space specific biases. since the estimated uncertainties stem from the same The negative logarithmic profile likelihood ratios source. For the same reason, the uncertainty from missing −2Δ lnðΛÞðBH→inv ; θÞ as a function of BH→inv of the higher order corrections on the Emiss T observable in the individual analyses and of the combined Run 2 result dominant background from diboson production in the are shown in Fig. 1, corresponding to a best-fit combined ZðlepÞH search is treated as correlated. All other back- value of BH→inv ¼ 0.20  0.10. The dominant uncertainty ground modeling uncertainties are considered uncorrelated. sources are finite event yields in data and MC simulations, The impact of these correlation assumptions on the com- reconstruction of jets and leptons, and modeling of bined BH→inv limit is found to be at most 0.005. In addition, diboson and W=Z þ jets production. In absence of a the impact on BH→inv in scenarios ranging from full anti- significant excess, an upper limit at 95% C.L. of BH→inv < correlation to full correlation is studied using the best linear 0.38ð0.21þ0.08 −0.06 Þ is observed (expected) with the CLs for- unbiased estimator (BLUE) [57] for the components of the malism [53] using the profile likelihood ratio as a test JES uncertainty, the V þ jets background, and diboson statistic. The excess in data corresponds to a pSM value of production that are nominally not correlated due to differ- 3% under the SM hypothesis of BH→inv ≃ 10−3 , and is a ent parametrizations in Run 1 and 2. The resulting absolute direct consequence of the excesses that are present in each effect on the BH→inv limit is at most 0.01. of the three input analyses, see Table I. Each of the The observed −2Δ lnðΛÞðBH→inv ; θÞ ratio of the com- individual analyses has been scrutinized and these excesses bined Run 1 þ 2 result is represented in Fig. 1, alongside have been found nonsignificant and independent. the individual Run 1 and Run 2 combinations. A best-fit Subsequently, the above Run 2 result is combined with value of BH→inv ¼ 0.13  0.08 is obtained, corresponding the Run 1 searches for H → inv decays [36]. Because of the to an observed (expected) upper limit of BH→inv < differences between the detector layouts and data-taking 0.26ð0.17þ0.07 −0.05 Þ at 95% C.L. The pSM value under the conditions, reconstruction algorithms and their calibrations, SM hypothesis is 10%, and the compatibility between the and treatment of systematic uncertainties, the correlations Run 1 and Run 2 results is 1.5 standard deviations. The between the runs are not clearly identifiable. Hence, no final result, together with the results in the individual Run 2 correlations between Run 1 and 2 are assumed for most analyses as well as the Run 2-only and the Run 1-only instrumental uncertainties. The uncertainties related to the combinations, are summarized in Table I, and the upper modeling of the calorimeter response dependence on jet limits on BH→inv are graphically represented in Fig. 2. 231801-3 PHYSICAL REVIEW LETTERS 122, 231801 (2019) 1 ATLAS reduced by m2H [33], excluding σ WIMP-N values down to s = 7 TeV, 4.7 fb-1 -1 10−46 cm2 . While the ATLAS exclusion limits extend to s = 8 TeV, 20.3 fb mWIMP < 1 GeV, that region is subject to uncertainties in Upper limit on BH→ inv -1 0.8 s = 13 TeV, 36.1 fb Observed limit modelling of the nuclear recoil and is therefore not included Expected limit ±1σ 0.6 Expected limit ±2σ in Fig. 3. All limits at 95% CL In summary, direct searches for invisible Higgs pffiffiffi 0.4 boson decays using 36.1 fb−1 of pp collision data at s ¼ 13 TeV recorded in 2015 and 2016 in the VBF, ZðlepÞH, 0.2 and VðhadÞH topologies are statistically combined assuming SM-like Higgs boson production. An upper 0 limit on the invisible Higgs branching ratio of BH→inv < V(had)H Z(lep)H VBF Combined Combined Combined Run 2 Run 2 Run 2 Run 2 Run 1 Run 1+2 0.38ð0.21þ0.08 −0.06 Þ is observed (expected) at 95% C.L. A statistical combination of this result with the combination FIG. 2. The observed and expected upper limits on BH→inv at of direct H → inv searches using up to 4.7 fb−1 of pp 95% C.L. from direct searches for invisible decays of the pffiffiffi 125 GeV Higgs boson and their statistical combinations in collision data at s ¼ 7 TeV and up to 20.3 fb−1 at 8 TeV Run 1 and 2. collected in Run 1 of the LHC yields an observed þ0.07 (expected) upper limit of BH→inv < 0.26ð0.17−0.05 Þ at 95% C.L. The combined Run 1 þ 2 result is translated The results are consistent with a similar statistical combi- into upper limits on the WIMP-nucleon scattering cross nation in Ref. [40]. section for Higgs portal models. The derived limits range The constraint from the combined observed Run 1 þ 2 down to 2 × 10−45 cm2 in the scalar and 10−46 cm2 in the exclusion limit of BH→inv < 0.24 at 90% C.L. is compared fermion WIMP scenarios, highlighting the complementar- to the results from representative direct DM detection ity of DM searches at the LHC and direct detection experiments [58–62] in Fig. 3. This comparison is per- experiments. formed in the context of Higgs portal models [63]. The translation of the H → inv result into a weak interacting We thank CERN for the very successful operation of the massive particle–nucleon scattering cross section σ WIMP-N LHC, as well as the support staff from our institutions relies on an effective field theory approach [33] under the without whom ATLAS could not be operated efficiently. assumption that invisible Higgs decays to a pair of WIMPs We acknowledge the support of ANPCyT, Argentina; are kinematically possible and that the WIMP is a scalar YerPhI, Armenia; ARC, Australia; BMWFW and FWF, or a fermion [23,64,65], using the nuclear form factor Austria; ANAS, Azerbaijan; SSTC, Belarus; CNPq and f N ¼ 0.308  0.018 [66]. The excluded σ WIMP-N values FAPESP, Brazil; NSERC, NRC and CFI, Canada; CERN; range down to 2 × 10−45 cm2 in the scalar WIMP scenario. CONICYT, Chile; CAS, MOST and NSFC, China; In the fermion WIMP case, the effective coupling is COLCIENCIAS, Colombia; MSMT CR, MPO CR and VSC CR, Czech Republic; DNRF and DNSRC, Denmark; IN2P3-CNRS, CEA-DRF/IRFU, France; SRNSFG, observed ATLAS Georgia; BMBF, HGF, and MPG, Germany; GSRT, B H → inv < 0.24 s = 7 TeV, 4.7 fb-1 10−40 All limits at 90% CL s = 8 TeV, 20.3 fb-1 Greece; RGC, Hong Kong SAR, China; ISF and s = 13 TeV, 36.1 fb-1 Benoziyo Center, Israel; INFN, Italy; MEXT and JSPS, Japan; CNRST, Morocco; NWO, Netherlands; RCN, σ WIMP-N [cm2] Higgs portals 10−42 Scalar WIMP Norway; MNiSW and NCN, Poland; FCT, Portugal; Fermion WIMP Other experiments MNE/IFA, Romania; MES of Russia and NRC KI, Cresst-III 10−44 DarkSide50 Russian Federation; JINR; MESTD, Serbia; MSSR, LUX Slovakia; ARRS and MIZŠ, Slovenia; DST/NRF, South PandaX-II Africa; MINECO, Spain; SRC and Wallenberg Foundation, 10−46 Xenon1T Sweden; SERI, SNSF and Cantons of Bern and Geneva, 1 10 102 103 104 Switzerland; MOST, Taiwan; TAEK, Turkey; STFC, mWIMP [GeV] United Kingdom; DOE and NSF, United States of America. In addition, individual groups and members have FIG. 3. Comparison of the upper limits at 90% C.L. from direct received support from BCKDF, CANARIE, CRC and detection experiments [58–62] on the spin-independent WIMP- nucleon scattering cross section to the observed exclusion limits Compute Canada, Canada; COST, ERC, ERDF, Horizon from this analysis, assuming Higgs portal scenarios where the 2020, and Marie Skłodowska-Curie Actions, European 125 GeV Higgs boson decays to a pair of DM particles [33,63]. Union; Investissements d’ Avenir Labex and Idex, ANR, The regions above the limit contours are excluded in the range France; DFG and AvH Foundation, Germany; Herakleitos, shown in the plot. Thales and Aristeia programmes co-financed by EU-ESF 231801-4 PHYSICAL REVIEW LETTERS 122, 231801 (2019) and the Greek NSRF, Greece; BSF-NSF and GIF, Israel; [17] A. Datta, K. Huitu, J. Laamanen, and B. 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Alberghi,23b,23a J. Albert,176 M. J. Alconada Verzini,88 S. Alderweireldt,119 M. Aleksa,36 I. N. Aleksandrov,79 C. Alexa,27b D. Alexandre,19 T. Alexopoulos,10 A. Alfonsi,120 M. Alhroob,128 B. Ali,142 G. Alimonti,68a J. Alison,37 S. P. Alkire,148 C. Allaire,132 B. M. M. Allbrooke,156 B. W. Allen,131 P. P. Allport,21 A. Aloisio,69a,69b A. Alonso,40 F. Alonso,88 C. Alpigiani,148 A. A. Alshehri,57 M. I. Alstaty,101 M. Alvarez Estevez,98 B. Alvarez Gonzalez,36 D. Álvarez Piqueras,174 M. G. Alviggi,69a,69b Y. Amaral Coutinho,80b A. Ambler,103 L. Ambroz,135 C. Amelung,26 D. Amidei,105 S. P. Amor Dos Santos,140a,140c S. Amoroso,46 C. S. Amrouche,54 F. An,78 C. Anastopoulos,149 N. Andari,145 T. Andeen,11 C. F. Anders,61b J. K. Anders,20 A. Andreazza,68a,68b V. Andrei,61a C. R. Anelli,176 S. Angelidakis,38 I. Angelozzi,120 A. Angerami,39 A. V. Anisenkov,122b,122a A. Annovi,71a C. Antel,61a M. T. Anthony,149 M. Antonelli,51 D. J. A. Antrim,171 F. Anulli,72a M. Aoki,81 J. A. Aparisi Pozo,174 L. 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D’Auria,68a,68b W. Davey,24 C. David,46 T. Davidek,143 D. R. Davis,49 E. Dawe,104 I. Dawson,149 K. De,8 R. De Asmundis,69a A. De Benedetti,128 M. De Beurs,120 S. De Castro,23b,23a S. De Cecco,72a,72b N. De Groot,119 P. de Jong,120 H. De la Torre,106 A. De Maria,15c D. De Pedis,72a A. De Salvo,72a U. De Sanctis,73a,73b M. De Santis,73a,73b A. De Santo,156 K. De Vasconcelos Corga,101 J. B. De Vivie De Regie,132 C. Debenedetti,146 D. V. Dedovich,79 A. M. Deiana,42 M. Del Gaudio,41b,41a J. Del Peso,98 Y. Delabat Diaz,46 D. Delgove,132 F. Deliot,145 C. M. Delitzsch,7 M. Della Pietra,69a,69b D. Della Volpe,54 A. Dell’Acqua,36 L. Dell’Asta,25 M. Delmastro,5 C. Delporte,132 P. A. Delsart,58 D. A. DeMarco,167 S. Demers,183 M. Demichev,79 G. Demontigny,109 S. P. Denisov,123 D. Denysiuk,120 L. D’Eramo,136 D. Derendarz,84 J. E. Derkaoui,35d F. Derue,136 P. Dervan,90 K. Desch,24 C. Deterre,46 K. Dette,167 M. R. Devesa,30 P. O. Deviveiros,36 A. Dewhurst,144 S. Dhaliwal,26 F. A. Di Bello,54 A. 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Dumancic,180 231801-8 PHYSICAL REVIEW LETTERS 122, 231801 (2019) A. E. Dumitriu,27b A. K. Duncan,57 M. Dunford,61a A. Duperrin,101 H. Duran Yildiz,4a M. Düren,56 A. Durglishvili,159b D. Duschinger,48 B. Dutta,46 D. Duvnjak,1 G. I. Dyckes,137 M. Dyndal,46 S. Dysch,100 B. S. Dziedzic,84 K. M. Ecker,115 R. C. Edgar,105 T. Eifert,36 G. Eigen,17 K. Einsweiler,18 T. Ekelof,172 M. El Kacimi,35c R. El Kosseifi,101 V. Ellajosyula,172 M. Ellert,172 F. Ellinghaus,182 A. A. Elliot,92 N. Ellis,36 J. Elmsheuser,29 M. Elsing,36 D. Emeliyanov,144 A. Emerman,39 Y. Enari,163 J. S. Ennis,178 M. B. Epland,49 J. Erdmann,47 A. Ereditato,20 M. Escalier,132 C. Escobar,174 O. Estrada Pastor,174 A. I. Etienvre,145 E. Etzion,161 H. Evans,65 A. Ezhilov,138 M. Ezzi,35e F. Fabbri,57 L. Fabbri,23b,23a V. Fabiani,119 G. Facini,94 R. M. Faisca Rodrigues Pereira,140a R. M. Fakhrutdinov,123 S. Falciano,72a P. J. Falke,5 S. Falke,5 J. Faltova,143 Y. Fang,15a Y. Fang,15a G. Fanourakis,44 M. Fanti,68a,68b A. Farbin,8 A. Farilla,74a E. M. Farina,70a,70b T. Farooque,106 S. Farrell,18 S. M. Farrington,178 P. Farthouat,36 F. Fassi,35e P. Fassnacht,36 D. Fassouliotis,9 M. Faucci Giannelli,50 W. J. Fawcett,32 L. Fayard,132 O. L. Fedin,138,p W. Fedorko,175 M. Feickert,42 S. Feigl,134 L. Feligioni,101 A. Fell,149 C. Feng,60b E. J. Feng,36 M. Feng,49 M. J. Fenton,57 A. B. Fenyuk,123 J. Ferrando,46 A. Ferrari,172 P. Ferrari,120 R. Ferrari,70a D. E. Ferreira de Lima,61b A. Ferrer,174 D. Ferrere,54 C. Ferretti,105 F. Fiedler,99 A. Filipčič,91 F. Filthaut,119 K. D. Finelli,25 M. C. N. Fiolhais,140a L. Fiorini,174 C. Fischer,14 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 D. Fournier,132 H. Fox,89 S. Fracchia,149 P. Francavilla,71a,71b M. Franchini,23b,23a S. Franchino,61a D. Francis,36 L. Franconi,20 M. Franklin,59 M. Frate,171 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,140c 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,g 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 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 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,e M. P. Giordani,66a,66c F. M. Giorgi,23b P. F. Giraud,145 G. Giugliarelli,66a,66c D. Giugni,68a F. Giuli,135 M. Giulini,61b S. Gkaitatzis,162 I. Gkialas,9,q 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 C. R. Goudet,132 D. Goujdami,35c A. G. Goussiou,148 N. Govender,33b,r C. Goy,5 E. Gozani,160 I. Grabowska-Bold,83a P. O. J. Gradin,172 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 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,s S. Grinstein,14,t 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,u 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,v L. Han,60a S. Han,15a,15d K. Hanagaki,81,w 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. Hauswald,48 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,x 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 231801-9 PHYSICAL REVIEW LETTERS 122, 231801 (2019) 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,y 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,z 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 D. O. Jamin,129 R. Jansky,54 J. Janssen,24 M. Janus,53 P. A. Janus,83a G. Jarlskog,96 N. Javadov,79,y T. Javůrek,36 M. Javurkova,52 F. Jeanneau,145 L. Jeanty,131 J. Jejelava,159a,aa A. Jelinskas,178 P. Jenni,52,bb J. Jeong,46 N. Jeong,46 S. Jézéquel,5 H. Ji,181 J. Jia,155 H. Jiang,78 Y. Jiang,60a Z. Jiang,153,cc 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,140b J. Jovicevic,168a X. Ju,18 J. J. Junggeburth,115 A. Juste Rozas,14,t A. Kaczmarska,84 M. Kado,132 H. Kagan,126 M. Kagan,153 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 J. J. Kempster,21 J. Kendrick,21 O. Kepka,141 S. Kersten,182 B. P. Kerševan,91 S. Ketabchi Haghighat,167 R. A. Keyes,103 M. Khader,173 F. Khalil-Zada,13 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 Y. K. Kim,37 N. Kimura,66a,66c O. M. Kind,19 B. T. King,90,a D. Kirchmeier,48 J. Kirk,144 A. E. Kiryunin,115 T. Kishimoto,163 V. Kitali,46 O. Kivernyk,5 E. Kladiva,28b,a 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. Kondo,81 N. Kondrashova,60c K. Köneke,52 A. C. König,119 T. Kono,125 R. Konoplich,124,dd 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 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,ee 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 J. L. La Rosa Navarro,80d 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 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 231801-10 PHYSICAL REVIEW LETTERS 122, 231801 (2019) 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,147a 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,ff M. A. L. Leite,80d R. Leitner,143 D. Lellouch,180,a 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,gg 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. 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,hh A. Lister,175 A. M. Litke,146 J. D. Little,8 B. Liu,78 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 H. Lu,63a 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,137,140b 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 C. B. Martin,126 T. A. Martin,178 V. J. Martin,50 B. Martin dit Latour,17 M. Martinez,14,t V. I. Martinez Outschoorn,102 S. Martin-Haugh,144 V. S. Martoiu,27b A. C. Martyniuk,94 A. Marzin,36 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 G. Mchedlidze,53 M. A. McKay,42 K. D. McLean,176 S. J. McMahon,144 P. C. McNamara,104 C. J. McNicol,178 R. A. McPherson,176,n 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 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,cc 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 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,10 B. Moser,120 M. Mosidze,159b H. J. Moss,149 J. Moss,31,ii K. Motohashi,165 E. Mountricha,36 E. J. W. Moyse,102 S. Muanza,101 F. Mueller,115 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 231801-11 PHYSICAL REVIEW LETTERS 122, 231801 (2019) A. G. Myagkov,123,jj 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,a P. Y. Nechaeva,110 F. Nechansky,46 T. J. Neep,145 A. Negri,70a,70b M. Negrini,23b S. Nektarijevic,119 C. Nellist,53 M. E. Nelson,135 S. Nemecek,141 P. Nemethy,124 M. Nessi,36,kk 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,jj 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. Nuti,104 F. G. Oakham,34,e 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 B. Osculati,55b,55a,a 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,q A. Paramonov,6 D. Paredes Hernandez,63b S. R. Paredes Saenz,135 B. Parida,166 T. H. Park,167 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,140b S. V. Peleganchuk,122b,122a O. Penc,141 C. Peng,15a H. Peng,60a B. S. Peralva,80a M. M. Perego,132 A. P. Pereira Peixoto,140a,140e D. V. Perepelitsa,29 F. Peri,19 L. Perini,68a,68b H. Pernegger,36 S. Perrella,69a,69b V. D. Peshekhonov,79,a K. Peters,46 R. F. Y. Peters,100 B. A. Petersen,36 T. C. Petersen,40 E. Petit,58 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 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,36 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,136 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 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 R. G. Reed,33c K. Reeves,43 L. Rehnisch,19 J. Reichert,137 D. Reikher,161 A. Reiss,99 A. Rej,151 C. Rembser,36 H. Ren,15a 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,n D. Robinson,32 J. E. M. Robinson,46 A. Robson,57 E. Rocco,99 C. Roda,71a,71b Y. Rodina,101 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 J. H. N. Rosten,32 R. Rosten,14 231801-12 PHYSICAL REVIEW LETTERS 122, 231801 (2019) M. Rotaru,27b J. Rothberg,148 D. Rousseau,132 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,ll Y. F. Ryabov,138 M. Rybar,39 G. Rybkin,132 S. Ryu,6 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 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,dd D. Salamani,54 G. Salamanna,74a,74b J. E. Salazar Loyola,147b P. H. Sales De Bruin,172 D. Salihagic,115,a 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 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,e N. Savic,115 R. Sawada,163 C. Sawyer,144 L. Sawyer,95,mm 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 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 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,24 G. Sciolla,26 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. S. Sharma,1 A. Sharma,135 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,nn S. Shimizu,81 C. O. Shimmin,183 Y. Shimogama,179 M. Shimojima,116 I. P. J. Shipsey,135 S. Shirabe,87 M. Shiyakova,79,oo 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 M. Simon,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,pp O. Smirnova,96 J. W. Smith,53 M. Smizanska,89 K. Smolek,142 A. Smykiewicz,84 A. A. Snesarev,110 I. M. Snyder,131 S. Snyder,29 R. Sobie,176,n A. M. Soffa,171 A. Soffer,161 A. Søgaard,50 F. Sohns,53 G. Sokhrannyi,91 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,qq A. M. Soukharev,122b,122a D. South,46 S. Spagnolo,67a,67b M. Spalla,115 M. Spangenberg,178 F. Spanò,93 D. Sperlich,19 T. M. Spieker,61a R. Spighi,23b G. Spigo,36 L. A. Spiller,104 M. Spina,156 D. P. Spiteri,57 M. Spousta,143 A. Stabile,68a,68b B. L. Stamas,121 R. Stamen,61a M. Stamenkovic,120 S. Stamm,19 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 B. Stelzer,152 H. J. Stelzer,36 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 A. Sydorenko,99 I. Sykora,28a M. Sykora,143 T. Sykora,143 D. Ta,99 K. Tackmann,46,rr 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 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,ss 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 231801-13 PHYSICAL REVIEW LETTERS 122, 231801 (2019) A. J. Taylor,50 G. N. Taylor,104 P. T. E. 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,n 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,tt 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,cc 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,uu 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,ee A. Tsirigotis,162 N. Tsirintanis,9 V. Tsiskaridze,155 E. G. Tskhadadze,159a M. Tsopoulou,162 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,vv R. J. Turner,21 R. T. Turra,68a P. M. Tuts,39 S. Tzamarias,162 E. Tzovara,99 G. Ucchielli,47 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 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 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,e N. Viaux Maira,147b M. Vicente Barreto Pinto,54 I. Vichou,173,a 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 G. Volpi,14 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 S. Wahrmund,48 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,136 R. Wang,60a R. Wang,6 S. M. Wang,158 W. T. Wang,60a W. Wang,15c,ww W. X. Wang,60a,ww Y. Wang,60a,gg Z. Wang,60c C. Wanotayaroj,46 A. Warburton,103 C. P. Ward,32 D. R. Wardrope,94 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 R. White,147b D. Whiteson,171 B. W. Whitmore,89 F. J. Wickens,144 W. Wiedenmann,181 M. Wielers,144 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,ss 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 E. Yigitbasi,25 E. Yildirim,99 K. Yorita,179 K. Yoshihara,137 C. J. S. Young,36 C. Young,153 J. Yu,78 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,jj 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 231801-14 PHYSICAL REVIEW LETTERS 122, 231801 (2019) 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 and L. Zwalinski36 (ATLAS Collaboration) 1 Department of Physics, University of Adelaide, Adelaide, Australia 2 Physics Department, SUNY Albany, Albany, New York, USA 3 Department of Physics, University of Alberta, Edmonton, Alberta, Canada 4a Department of Physics, Ankara University, Ankara, Turkey 4b Istanbul Aydin University, Istanbul, Turkey 4c 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, Illinois, USA 7 Department of Physics, University of Arizona, Tucson, Arizona, USA 8 Department of Physics, University of Texas at Arlington, Arlington, Texas, USA 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, Texas, USA 12a Bahcesehir University, Faculty of Engineering and Natural Sciences, Istanbul, Turkey 12b Istanbul Bilgi University, Faculty of Engineering and Natural Sciences, Istanbul, Turkey 12c Department of Physics, Bogazici University, Istanbul, Turkey 12d 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 15a Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China 15b Physics Department, Tsinghua University, Beijing, China 15c Department of Physics, Nanjing University, Nanjing, China 15d 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, California, USA 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 23a INFN Bologna and Universita’ di Bologna, Dipartimento di Fisica, Italy 23b INFN Sezione di Bologna, Bologna, Italy 24 Physikalisches Institut, Universität Bonn, Bonn, Germany 25 Department of Physics, Boston University, Boston, Massachusetts, USA 26 Department of Physics, Brandeis University, Waltham, Massachusetts, USA 27a Transilvania University of Brasov, Brasov, Romania 27b Horia Hulubei National Institute of Physics and Nuclear Engineering, Bucharest, Romania 27c Department of Physics, Alexandru Ioan Cuza University of Iasi, Iasi, Romania 27d National Institute for Research and Development of Isotopic and Molecular Technologies, Physics Department, Cluj-Napoca, Romania 27e University Politehnica Bucharest, Bucharest, Romania 27f West University in Timisoara, Timisoara, Romania 28a Faculty of Mathematics, Physics and Informatics, Comenius University, Bratislava, Slovak Republic 28b Department of Subnuclear Physics, Institute of Experimental Physics of the Slovak Academy of Sciences, Kosice, Slovak Republic 29 Physics Department, Brookhaven National Laboratory, Upton, New York, USA 30 Departamento de Física, Universidad de Buenos Aires, Buenos Aires, Argentina 31 California State University, California, USA 32 Cavendish Laboratory, University of Cambridge, Cambridge, United Kingdom 33a Department of Physics, University of Cape Town, Cape Town, South Africa 33b Department of Mechanical Engineering Science, University of Johannesburg, Johannesburg, South Africa 33c School of Physics, University of the Witwatersrand, Johannesburg, South Africa 34 Department of Physics, Carleton University, Ottawa, Ontario, Canada 231801-15 PHYSICAL REVIEW LETTERS 122, 231801 (2019) 35a Faculté des Sciences Ain Chock, Réseau Universitaire de Physique des Hautes Energies—Université Hassan II, Casablanca, Morocco 35b Faculté des Sciences, Université Ibn-Tofail, Kénitra, Morocco 35c Faculté des Sciences Semlalia, Université Cadi Ayyad, LPHEA-Marrakech, Morocco 35d Faculté des Sciences, Université Mohamed Premier and LPTPM, Oujda, Morocco 35e Faculté des sciences, Université Mohammed V, Rabat, Morocco 36 CERN, Geneva, Switzerland 37 Enrico Fermi Institute, University of Chicago, Chicago, Illinois, USA 38 LPC, Université Clermont Auvergne, CNRS/IN2P3, Clermont-Ferrand, France 39 Nevis Laboratory, Columbia University, Irvington, New York, USA 40 Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark 41a Dipartimento di Fisica, Università della Calabria, Rende, Italy 41b INFN Gruppo Collegato di Cosenza, Laboratori Nazionali di Frascati, Frascati, Italy 42 Physics Department, Southern Methodist University, Dallas, Texas, USA 43 Physics Department, University of Texas at Dallas, Richardson, Texas, USA 44 National Centre for Scientific Research “Demokritos”, Agia Paraskevi, Greece 45a Department of Physics, Stockholm University, Sweden 45b 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, North Carolina, USA 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 55a Dipartimento di Fisica, Università di Genova, Genova, Italy 55b INFN Sezione di Genova, 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, Massachusetts, USA 60a Department of Modern Physics and State Key Laboratory of Particle Detection and Electronics, University of Science and Technology of China, Hefei, China 60b Institute of Frontier and Interdisciplinary Science and Key Laboratory of Particle Physics and Particle Irradiation (MOE), Shandong University, Qingdao, China 60c School of Physics and Astronomy, Shanghai Jiao Tong University, KLPPAC-MoE, SKLPPC, Shanghai, China 60d Tsung-Dao Lee Institute, Shanghai, China 61a Kirchhoff-Institut für Physik, Ruprecht-Karls-Universität Heidelberg, Heidelberg, Germany 61b Physikalisches Institut, Ruprecht-Karls-Universität Heidelberg, Heidelberg, Germany 62 Faculty of Applied Information Science, Hiroshima Institute of Technology, Hiroshima, Japan 63a Department of Physics, Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China 63b Department of Physics, University of Hong Kong, Hong Kong, China 63c 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, Indiana, USA 66a INFN Gruppo Collegato di Udine, Sezione di Trieste, Udine, Italy 66b ICTP, Trieste, Italy 66c Dipartimento Politecnico di Ingegneria e Architettura, Università di Udine, Udine, Italy 67a INFN Sezione di Lecce, Lecce, Italy 67b Dipartimento di Matematica e Fisica, Università del Salento, Lecce, Italy 68a INFN Sezione di Milano, Italy 68b Dipartimento di Fisica, Università di Milano, Milano, Italy 69a INFN Sezione di Napoli, Napoli, Italy 69b Dipartimento di Fisica, Università di Napoli, Napoli, Italy 70a INFN Sezione di Pavia, Pavia, Italy 70b Dipartimento di Fisica, Università di Pavia, Pavia, Italy 71a INFN Sezione di Pisa, Pisa, Italy 231801-16 PHYSICAL REVIEW LETTERS 122, 231801 (2019) 71b Dipartimento di Fisica E. Fermi, Università di Pisa, Pisa, Italy 72a INFN Sezione di Roma, Roma, Italy 72b Dipartimento di Fisica, Sapienza Università di Roma, Roma, Italy 73a INFN Sezione di Roma Tor Vergata, Roma, Italy 73b Dipartimento di Fisica, Università di Roma Tor Vergata, Roma, Italy 74a INFN Sezione di Roma Tre, Italy 74b Dipartimento di Matematica e Fisica, Università Roma Tre, Roma, Italy 75a INFN-TIFPA, Trento, Italy 75b Università degli Studi di Trento, Trento, Italy 76 Institut für Astro- und Teilchenphysik, Leopold-Franzens-Universität, Innsbruck, Austria 77 University of Iowa, Iowa City, Iowa, USA 78 Department of Physics and Astronomy, Iowa State University, Ames, Iowa, USA 79 Joint Institute for Nuclear Research, Dubna, Russia 80a Departamento de Engenharia Elétrica, Universidade Federal de Juiz de Fora (UFJF), Juiz de Fora, Brazil 80b Universidade Federal do Rio De Janeiro COPPE/EE/IF, Rio de Janeiro, Brazil 80c Universidade Federal de São João del Rei (UFSJ), São João del Rei, Brazil 80d 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 83a AGH University of Science and Technology, Faculty of Physics and Applied Computer Science, Krakow, Poland 83b 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, Louisiana, USA 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, Massachusetts, USA 103 Department of Physics, McGill University, Montreal, Quebec, Canada 104 School of Physics, University of Melbourne, Victoria, Australia 105 Department of Physics, University of Michigan, Ann Arbor, Michigan, USA 106 Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan, USA 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, Quebec, 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, New Mexico, USA 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, Illinois, USA 231801-17 PHYSICAL REVIEW LETTERS 122, 231801 (2019) 122a Budker Institute of Nuclear Physics and NSU, SB RAS, Novosibirsk, Russia 122b 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, New York, USA 125 Ochanomizu University, Otsuka, Bunkyo-ku, Tokyo, Japan 126 The Ohio State University, Columbus, Ohio, USA 127 Faculty of Science, Okayama University, Okayama, Japan 128 Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, Norman, Oklahoma, USA 129 Department of Physics, Oklahoma State University, Stillwater, Oklahoma, USA 130 Palacký University, RCPTM, Joint Laboratory of Optics, Olomouc, Czech Republic 131 Center for High Energy Physics, University of Oregon, Eugene, Oregon, USA 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, Pennsylvania, USA 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, Pennsylvania, USA 140a Laboratório de Instrumentação e Física Experimental de Partículas—LIP, Portugal 140b Departamento de Física, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal 140c Departamento de Física, Universidade de Coimbra, Coimbra, Portugal 140d Centro de Física Nuclear da Universidade de Lisboa, Lisboa, Portugal 140e Departamento de Física, Universidade do Minho, Braga, Portugal 140f Universidad de Granada, Granada (Spain), Spain 140g 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 145 IRFU, CEA, Université Paris-Saclay, Gif-sur-Yvette, France 146 Santa Cruz Institute for Particle Physics, University of California Santa Cruz, Santa Cruz, California, USA 147a Departamento de Física, Pontificia Universidad Católica de Chile, Santiago, Chile 147b Departamento de Física, Universidad Técnica Federico Santa María, Valparaíso, Chile 148 Department of Physics, University of Washington, Seattle, Washington, USA 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, British Columbia, Canada 153 SLAC National Accelerator Laboratory, Stanford, California, USA 154 Physics Department, Royal Institute of Technology, Stockholm, Sweden 155 Departments of Physics and Astronomy, Stony Brook University, Stony Brook, New York, USA 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 159a E. Andronikashvili Institute of Physics, Iv. Javakhishvili Tbilisi State University, Tbilisi, Georgia 159b 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, Ontario, Canada 168a TRIUMF, Vancouver, British Columbia, Canada 168b Department of Physics and Astronomy, York University, Toronto, Ontario, 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, Massachusetts, USA 231801-18 PHYSICAL REVIEW LETTERS 122, 231801 (2019) 171 Department of Physics and Astronomy, University of California Irvine, Irvine, California, USA 172 Department of Physics and Astronomy, University of Uppsala, Uppsala, Sweden 173 Department of Physics, University of Illinois, Urbana, Illinois, USA 174 Instituto de Física Corpuscular (IFIC), Centro Mixto Universidad de Valencia—CSIC, Valencia, Spain 175 Department of Physics, University of British Columbia, Vancouver, British Columbia, Canada 176 Department of Physics and Astronomy, University of Victoria, Victoria, British Columbia, 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, Wisconsin, USA 182 Fakultät für Mathematik und Naturwissenschaften, Fachgruppe Physik, Bergische Universität Wuppertal, Wuppertal, Germany 183 Department of Physics, Yale University, New Haven, Connecticut, USA 184 Yerevan Physics Institute, Yerevan, Armenia a Deceased. b Also at Department of Physics, King’s College London, London, United Kingdom. c Also at Istanbul University, Dept. of Physics, Istanbul, Turkey. d Also at Instituto de Fisica Teorica, IFT-UAM/CSIC, Madrid, Spain. e Also at TRIUMF, Vancouver, British Columbia, Canada. f Also at Department of Physics and Astronomy, University of Louisville, Louisville, Kentucky, USA. g Also at Department of Physics, California State University, Fresno, California, USA. h Also at Department of Physics, University of Fribourg, Fribourg, Switzerland. i Also at Departament de Fisica de la Universitat Autonoma de Barcelona, Barcelona, Spain. j Also at Tomsk State University, Tomsk, and Moscow Institute of Physics and Technology State University, Dolgoprudny, Russia. k Also at The Collaborative Innovation Center of Quantum Matter (CICQM), Beijing, China. l Also at Departamento de Física, Instituto Superior Técnico, Universidade de Lisboa, Lisboa, Portugal. m Also at Universita di Napoli Parthenope, Napoli, Italy. n Also at Institute of Particle Physics (IPP), Canada. o Also at Horia Hulubei National Institute of Physics and Nuclear Engineering, Bucharest, Romania. p Also at Department of Physics, St. Petersburg State Polytechnical University, St. Petersburg, Russia. q Also at Department of Financial and Management Engineering, University of the Aegean, Chios, Greece. r Also at Centre for High Performance Computing, CSIR Campus, Rosebank, Cape Town, South Africa. s Also at Department of Physics, California State University, East Bay, Hayward, California, USA. t Also at Institucio Catalana de Recerca i Estudis Avancats, ICREA, Barcelona, Spain. u Also at Department of Physics, University of Michigan, Ann Arbor, Michigan, USA. v Also at LAL, Université Paris-Sud, CNRS/IN2P3, Université Paris-Saclay, Orsay, France. w Also at Graduate School of Science, Osaka University, Osaka, Japan. x Also at Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany. y Also at Institute of Physics, Azerbaijan Academy of Sciences, Baku, Azerbaijan. z Also at Institute for Mathematics, Astrophysics and Particle Physics, Radboud University Nijmegen/Nikhef, Nijmegen, Netherlands. aa Also at Institute of Theoretical Physics, Ilia State University, Tbilisi, Georgia. bb Also at CERN, Geneva, Switzerland. cc Also at Department of Physics, Stanford University, Stanford, California, USA. dd Also at Manhattan College, New York, New York, USA. ee Also at Joint Institute for Nuclear Research, Dubna, Russia. ff Also at Hellenic Open University, Patras, Greece. gg Also at LPNHE, Sorbonne Université, Paris Diderot Sorbonne Paris Cité, CNRS/IN2P3, Paris, France. hh Also at The City College of New York, New York, New York, USA. ii Also at Department of Physics, California State University, Sacramento, California, USA. jj Also at Moscow Institute of Physics and Technology State University, Dolgoprudny, Russia. kk Also at Département de Physique Nucléaire et Corpusculaire, Université de Genève, Genève, Switzerland. ll Also at Department of Physics and Astronomy, University of Sheffield, Sheffield, United Kingdom. mm Also at Louisiana Tech University, Ruston, Louisiana, USA. nn Also at School of Physics, Sun Yat-sen University, Guangzhou, China. oo Also at Institute for Nuclear Research and Nuclear Energy (INRNE) of the Bulgarian Academy of Sciences, Sofia, Bulgaria. pp Also at Faculty of Physics, M.V. Lomonosov Moscow State University, Moscow, Russia. qq Also at Department of Applied Physics and Astronomy, University of Sharjah, Sharjah, United Arab Emirates. rr Also at Institut für Experimentalphysik, Universität Hamburg, Hamburg, Germany. ss Also at CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille, France. 231801-19 PHYSICAL REVIEW LETTERS 122, 231801 (2019) tt Also at National Research Nuclear University MEPhI, Moscow, Russia. uu Also at Institute for Particle and Nuclear Physics, Wigner Research Centre for Physics, Budapest, Hungary. vv Also at Giresun University, Faculty of Engineering, Giresun, Turkey. ww Also at Institute of Physics, Academia Sinica, Taipei, Taiwan. 231801-20