Search for new phenomena in pp collisions in final states with tau leptons, b-jets, and missing transverse momentum with the ATLAS detector

Search for new phenomena in pp collisions in final states with tau leptons, b-jets, and missing transverse momentum with the ATLAS detector G. Aad et al.* (ATLAS Collaboration) (Received 18 August 2021; accepted 8 September 2021; published 21 December 2021) A search for new phenomena in final states with hadronically decaying tau leptons, b-jets, and missing transverse momentum is presented. The analyzed dataset comprises pp collision data at a center-of-mass energy of ffiffiffi s p¼13 TeV with an integrated luminosity of 139 fb−1, delivered by the Large Hadron Collider and recorded with the ATLAS detector from 2015 to 2018. The observed data are compatible with the expected Standard Model background. The results are interpreted in simplified models for two different scenarios. The first model is based on supersymmetry and considers pair production of top squarks, each of which decays into a b-quark, a neutrino and a tau slepton. Each tau slepton in turn decays into a tau lepton and a nearly massless gravitino. Within this model, top-squark masses up to 1.4 TeV can be excluded at the 95% confidence level over a wide range of tau-slepton masses. The second model considers pair production of leptoquarks with decays into third-generation leptons and quarks. Depending on the branching fraction into charged leptons, leptoquarks with masses up to around 1.25 TeV can be excluded at the 95% confidence level for the case of scalar leptoquarks and up to 1.8 TeV (1.5 TeV) for vector leptoquarks in a Yang–Mills (minimal-coupling) scenario. In addition, model-independent upper limits are set on the cross section of processes beyond the Standard Model. DOI: 10.1103/PhysRevD.104.112005 I. INTRODUCTION The Standard Model (SM) of particle physics has been verified to high precision. Despite its success, several observations have been made which have exposed the theory’s shortcomings in various aspects and fostered new theoretical ideas. Supersymmetry (SUSY) [1–7] is a framework for models that extend the symmetries underlying the SM by introducing superpartners of the known bosons and fermions with the same quantum numbers but a spin difference of half a unit. These models can address the gauge hierarchy problem [8–11]. When conservation of R-parity [12] is assumed, the lightest supersymmetric particle is stable and may provide a candidate particle for the cold dark matter component of the Universe [13,14]. The introduction of supersymmetric partner particles can also modify the renormalization group equations in such a way that the coupling constants of the SM electromagnetic, weak and strong interactions meet at one point at some high energy scale as expected in a grand unified theory [15]. Another possible way to extend the SM is to embed the SM symmetry group in an overarching symmetry group, such as SU(5) [16] in grand unification, which gives rise to a new class of bosons that carry nonzero baryon and lepton quantum numbers and are charged under all SM gauge groups. These leptoquarks (LQ), which can be either scalar or vector bosons, appear in a variety of SM extensions [17–21] and would provide an explanation for the structural similarities of the quark and lepton sectors in the SM. Processes mediated by the exchange of leptoquarks can violate lepton-flavor universality and have been proposed as an explanation [22–28] for the deviations from the SM predictions seen by many experiments in measurements of B-meson decays [29–37]. Contributions arising from leptoquarks with additional couplings to the muon could also bridge the gap [38,39] between the theoretical prediction for the anomalous magnetic moment of the muon ðg−2Þμ within the SM and the experimentally measured value, which is higher by 4.2σ[40]. In this paper, a search for physics beyond that described in the Standard Model is conducted using events with final states with one or more hadronically decaying tau leptons, one or more b-tagged jets and large missing transverse momentum. This is a signature that is sensitive to models in which the new particles preferentially decay into thirdgeneration SM particles. Two benchmark signal models are studied. The first model considers the production of supersymmetric partner states of the third-generation SM particles, while the second model foresees scalar *Full author list given at the end of the article. Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3. PHYSICAL REVIEW D 104, 112005 (2021) 2470-0010=2021=104(11)=112005(35) 112005-1 © 2021 CERN, for the ATLAS Collaboration leptoquarks that decay into third-generation SM particles. An additional interpretation, for which the analysis was not explicitly optimized, is provided for vector leptoquarks that decay into third-generation SM particles. The full run-2 dataset of proton–proton (pp) collisions recorded with the ATLAS detector at the Large Hadron Collider (LHC) is analyzed. This dataset corresponds to an integrated luminosity of 139 fb−1, taken from 2015 through 2018, at a center-of-mass energy of ffiffiffi s p¼13 TeV. The investigated SUSY signal model is motivated by gauge-mediated SUSY breaking (GMSB) [41–43] and natural gauge mediation [44]. In this R-parity-conserving scenario, only three SUSY particles are assumed to be sufficiently light to be relevant: the lighter scalar partner of the top quark ˜ t(top squark or stop), the lighter scalar partner of the tau lepton ˜τ(tau slepton or stau), and the spin-3=2partner of the graviton, the gravitino ˜ G. The top squark is assumed to be the lightest squark [45,46] and to be directly pair-produced through the strong interaction. The gravitino is assumed to be almost massless, making it the lightest SUSY particle (LSP) in this scenario. The search strategy is optimized using a simplified model [47–49] with this limited SUSY particle content, the model parameters being the scalar-fermion masses mð˜ tÞand mð˜τÞ. The decay chain is illustrated in the left diagram of Fig. 1:a three-body decay proceeding through an off shell chargino ˜ t→b˜τντfollowed by ˜τ→τ ˜ G. This model is referred to as the “stop-stau”signal model in the following. When the LSP is the gravitino, direct decays of SUSY particles into the gravitino LSP (plus a SM particle) are very unlikely due to its weak coupling, except for the next-to-lightest supersymmetric particle, which in R-parity-conserving scenarios has no other option than to decay into the gravitino LSP. Other SUSY models which instead assume the lightest neutralino ˜ χ0 1to be the LSP are not studied here, as this would favor a high branching fraction of ˜ t→t˜ χ0 1; this case has been studied elsewhere by the ATLAS Collaboration [50–52] and by the CMS Collaboration [53–56]. Previous searches by the ATLAS Collaboration for signals in this model used 20 fb−1of ffiffiffi s p¼8TeV data taken in run 1 [57] and 36.1fb−1of ffiffiffi s p¼13 TeV data taken in run 2 of the LHC [58]. No significant excess was observed in either of these searches, and thus limits were set on the masses of the top squark and tau slepton. These limits exclude top-squark masses of up to 1.16 TeVand tauslepton masses of up to 1.0 TeVat the 95% confidence level. The CMS Collaboration has published a related search in a simplified model with pair production of top squarks, which are also assumed to decay via tau sleptons or tau sneutrinos, but where the LSP is the lightest neutralino ˜ χ0 1instead of the gravitino [59]. This search is based on an integrated luminosity of 77.2fb−1and sets exclusion limits at the 95% confidence level on the top-squark mass of up to 1.1 TeV for a nearly massless neutralino. The previous ATLAS run-2 search in Ref. [58] made use of two event categories: events where one of the two tau leptons decays leptonically and the other hadronically were considered in addition to events where both tau leptons decay hadronically. While the branching fractions are almost the same for both categories, the leptonic decay of the tau lepton yields one neutrino more, which washes out the kinematic distributions and on average leads to a lower energy fraction carried by the lepton compared to the visible decay products from a hadronic tau-lepton decay. Taken together, the two effects significantly reduce the discriminative power of the selection requirements. As the sensitivity of the search is thus dominated by the category where both tau leptons decay hadronically, this paper considers only events with hadronically decaying tau leptons. These events are separated in two event categories (channels). One category selects events with at least two hadronically decaying tau leptons but no lighter leptons, at least one b-jet and large missing transverse momentum Emiss T(di-tau channel). The other category selects events with exactly one hadronically decaying tau lepton, no electrons or muons, at least two b-jets and large Emiss T (single-tau channel). The latter channel extends the sensitivity by covering the signal parameter space where the tau slepton is relatively light and one of the soft tau leptons easily escapes detection. Importantly, it also provides good sensitivity to events with pair-produced leptoquarks that decay into third-generation particles, which correspond to the second benchmark model. The second benchmark model used in the design of the analysis considers pair production of scalar leptoquarks. It assumes that these only couple to third-generation quarklepton pairs, following the minimal Buchmüller–Rückl– Wyler (BRW) model [60]. In addition to the coupling to the FIG. 1. Diagrams illustrating the production and decay of particles considered in the simplified models for the supersymmetric “stopstau”scenario (left) and for scalar leptoquarks of charge þ2 3e(middle) and −1 3e(right). G. AAD et al. PHYS. REV. D 104, 112005 (2021) 112005-2 third fermion generation that is probed in this analysis, leptoquarks would need to have cross-generational couplings in order to explain the anomalies observed in Bmeson decays. The search is carried out for both up-type scalar leptoquarks with fractional charge QðLQu 3Þ¼þ2 3e and decays LQu 3→tντ=bτ, and down-type scalar leptoquarks with QðLQd 3Þ¼−1 3eand decays LQd 3→bντ=tτ. The production and decay of the leptoquarks are illustrated in Fig. 1. The model parameters are the leptoquark mass mðLQu=d 3Þand the branching fraction BðLQu=d 3→ qlÞinto a quark and a charged lepton. For a branching fraction BðLQu=d 3→qlÞ∼0.5, most of the decays of the pair of third-generation leptoquarks yield a final state with one tau lepton, two b-jets and large Emiss Tfrom the tau neutrino. This signature matches that of the single-tau channel, which presents unique coverage of leptoquark masses at BðLQu=d 3→qlÞ∼0.5, but also has good sensitivity to a wide range of smaller or larger branching fractions. The scalar-LQ model is the same as was used in a previous ATLAS paper [61] detailing a search for thirdgeneration leptoquarks based on 36.1fb−1of data taken at ffiffiffi s p¼13 TeV. This earlier paper comprises a dedicated reoptimization of the ATLAS search for pair-produced Higgs bosons and four reinterpretations of ATLAS SUSY searches, one of which is the previous iteration of the stopstau search [58]. Leptoquark masses below at least 0.8 TeV are excluded at intermediate values of the branching fraction BðLQu=d 3→qlÞ, with the lower limit increasing at both small and large BðLQu=d 3→qlÞ, e.g., to 0.96 (1.02) TeV at BðLQu=d 3→qlÞ¼0(1) for down-type (up-type) leptoquarks. Two recent ATLAS searches for top or bottom squark pair production have been reinterpreted in the same up-type or down-type leptoquark model, respectively [50,62]. Another recent dedicated ATLAS search for pair-produced leptoquarks combines several event categories which all require at least one hadronically decaying tau lepton plus at least one electron or muon [63] and are complementary to the final states considered in this paper. It targets the down-type leptoquark model and excludes leptoquark masses up to 1.43 TeV assuming BðLQu=d 3→qlÞ¼1and up to 1.22 TeV assuming BðLQu=d 3→qlÞ¼0.5. The CMS Collaboration has published a search of the full run-2 dataset for single or pair production of scalar or vector leptoquarks coupling to thirdgeneration fermions, considering final-state signatures consisting of a top quark, a tau lepton, a neutrino, and either no or at least one additional b-tagged jet. This search excludes scalar leptoquarks with masses up to about 1.0 TeV [64]. CMS has also reported several searches for third-generation leptoquarks based on 35.9fb−1of run2 data [65–69], which typically set lower limits on the mass of scalar leptoquarks in the range of 0.9 to 1.1 TeV. An additional interpretation of the search results is provided for pair production of vector leptoquarks LQv 3. Again, it is assumed that the vector leptoquarks can only decay into third-generation SM particles. The electric charge of the vector leptoquarks and their decay modes are the same as those of the up-type scalar leptoquarks in the middle diagram of Fig. 1. The signal selection criteria were not explicitly optimized for this model, but the kinematic distributions of the decay products are similar for scalar and vector leptoquarks, except when the branching fraction of the leptoquarks into a quark and a charged lepton is small, where tau leptons and b-jets predominantly arise from the leptoquarks decaying into top quarks and neutrinos rather than directly from the leptoquark decays. The signal selection developed for scalar leptoquarks can thus be expected to also perform very well for the case of vector leptoquarks, although the relevant energy scales are slightly higher in this case due to the larger production cross sections at the same mass. As in the signal model with scalar leptoquarks, the parameters for the vector-leptoquark model are the leptoquark mass mðLQv 3Þand the branching fraction BðLQv 3→bτÞinto a quark and a charged lepton. This is the first time this model is used in a search for leptoquarks by the ATLAS Collaboration. Models with vector leptoquarks have been considered in several analyses by the CMS Collaboration, including the one in Ref. [64], which excludes vector leptoquarks decaying into t¯ ντ=bτþwith masses up to 1.65 TeV for pair production in the most favorable coupling scenario. II. ATLAS DETECTOR The ATLAS experiment [70–72] at the LHC is a multipurpose particle detector with a forward–backward symmetric cylindrical geometry and a near 4πcoverage in solid angle.1Itconsistsof aninnertrackingdetectorsurroundedby a thin superconducting solenoid providing a 2 T axial magnetic field, electromagnetic and hadronic calorimeters, and a muon spectrometer. The inner tracking detector covers the pseudorapidity range jηj<2.5. It consists of silicon pixel, silicon microstrip, and transition radiation tracking detectors. Lead/liquid-argon (LAr) sampling calorimeters provide electromagnetic (EM) energy measurements with high granularity. A steel/scintillator-tile hadronic calorimeter covers the central pseudorapidity range (jηj<1.7). The end cap and forward regions are instrumented with LAr calorimeters for EM and hadronic energy measurements up to 1ATLAS uses a right-handed coordinate system with its origin at the nominal interaction point (IP) in the center of the detector and the z-axis along the beam pipe. The x-axis points from the IP to the center of the LHC ring, and the y-axis points upwards. Cylindrical coordinates ðr; ϕÞare used in the transverse plane, ϕ being the azimuthal angle around the z-axis. The pseudorapidity is defined in terms of the polar angle θas η≡−ln tanðθ=2Þand is an approximation of the rapidity y≡0.5ln ½ðEþpzÞ=ðE−pzÞ in the high-energy limit. SEARCH FOR NEW PHENOMENA IN PP COLLISIONS IN …PHYS. REV. D 104, 112005 (2021) 112005-3 jηj¼4.9. The muon spectrometer surrounds the calorimeters and is based on three large superconducting air-core toroidal magnets with eight coils each. The muon spectrometer includes a system of precision tracking chambers and fast detectors for triggering. A two-level trigger system is usedtoselectevents[73]. The first-level trigger is implemented in hardware and uses a subset of the detector information to accept events at a rate below 100 kHz. This is followed by a software-based high-level trigger that reduces the accepted event rate to 1 kHz on average depending on the data-taking conditions. An extensive software suite [74] is used for real and simulated data reconstruction and analysis, for operation and in the trigger and data acquisition systems of the experiment. III. DATA AND SIMULATED EVENT SAMPLES The dataset used in this analysis was collected with the ATLAS detector in proton–proton collisions provided by the LHC during its second run from 2015 to 2018. The data was taken at a center-of-mass energy of ffiffiffi s p¼13 TeV with a minimum separation of 25 ns between consecutive crossings of proton bunches from the two beams. Events are selected with triggers on missing transverse momentum [75], and data-quality requirements are applied to ensure that all elements of the detectors were operational during data-taking [76]. The total integrated luminosity amounts to 139 fb−1with an uncertainty of 1.7% [77], obtained using the LUCID-2 detector [78] for the primary luminosity measurements. Monte Carlo (MC) simulation was used to generate samples of collision events, which model the expected kinematics of the investigated signal and SM background processes. Table Igives a detailed summary of the generation of the different MC samples used in the analysis. It lists the generators, the order of the cross section computation, the parton distribution function (PDF) sets, and the sets of tuned parameters (tunes) for the parton shower (PS). For background processes, the detector response was simulated [79] using the full modeling of the ATLAS detector in G EANT 4[80], while for the signal samples a faster variant of the simulation was used that relies on a parametrized response of the calorimeters [81]. Except for samples produced with S HERPA [82], which uses a dedicated parton-shower modeling and parameter tune developed by the S HERPA authors, the parton shower and hadronization simulation for all samples used the A14 tune [83], and the E VT G EN program [84] was used to model the decays of band c-hadrons in signal samples and background events. The effect of multiple concurrent interactions in the same and neighboring bunch crossings (pileup) was modeled by overlaying the hard-scattering events with simulated inelastic pp events generated with P YTHIA 8.186 [85] using the NNPDF2.3 LO set of PDFs [86] and the A3 tune [87]. All simulated events are processed with the same trigger, reconstruction and identification TABLE I. Simulated background and signal samples with the corresponding matrix element and parton shower (PS) generators. Also, the cross section order in αsused to normalize the event yield and the parton distribution function (PDF) sets used in the generator and PS simulation are given. Physics process Generator Parton shower Tune Cross section PDF (generator) PDF (PS) t¯ tP OWHEG B OX v2 [88–91] P YTHIA 8.230 [92] A14 [83] NNLO þNNLL [93] NNPDF3.0 NLO [94] NNPDF2.3 LO [86] Single top P OWHEG B OX v2 [89–91,95] P YTHIA 8.230 A14 NLO þNNLL [96–99] NNPDF3.0 NLO NNPDF2.3 LO Vþjets ðV¼W;ZÞS HERPA 2.2.1 [82] S HERPA 2.2.1 S HERPA default NNLO [100] NNPDF3.0 NNLO [94] NNPDF3.0 NNLO Diboson VV ðV¼W;ZÞ S HERPA 2.2.1 or 2.2.2 [82] S HERPA 2.2.1 or 2.2.2 S HERPA default NLO [101–103] NNPDF3.0 NNLO NNPDF3.0 NNLO Triboson VVV ðV¼W;ZÞ S HERPA 2.2.1 S HERPA 2.2.1 S HERPA default NLO [101–103] NNPDF3.0 NNLO NNPDF3.0 NNLO t¯ tþVðV¼W;ZÞM AD G RAPH [email protected] [104] P YTHIA 8.210 [92] A14 NLO [104,105] NNPDF3.0 NLO NNPDF2.3 LO t¯ tþHP OWHEG B OX v2 [90,91,106] P YTHIA 8.230 A14 NLO [104,105] NNPDF3.0 NLO NNPDF2.3 LO t¯ tþWW M AD G RAPH [email protected] [104] P YTHIA 8.186 [92] A14 NLO [104] NNPDF2.3 LO NNPDF2.3 LO t¯ tþWZ M AD G RAPH [email protected] P YTHIA 8.212 [92] A14 NLO [104] NNPDF3.0 NLO NNPDF2.3 LO tWZ M AD G RAPH [email protected] P YTHIA 8.212 A14 NLO [104] NNPDF3.0 NLO NNPDF2.3 LO tZ; t¯ tt; t¯ tt¯ tM AD G RAPH [email protected] P YTHIA 8.230 A14 NLO [104] NNPDF3.1 NLO [94] NNPDF2.3 LO Stop-stau M AD G RAPH [email protected] P YTHIA 8.212 A14 approx. NNLO þNNLL [107–110] NNPDF2.3 LO NNPDF2.3 LO Scalar LQ (LQu=d 3)M AD G RAPH [email protected] P YTHIA 8.230 A14 approx. NNLO þNNLL [107–110] NNPDF3.0 NLO NNPDF2.3 LO Vector LQ (LQv 3)M AD G RAPH [email protected] P YTHIA 8.244 A14 LO NNPDF3.0 NLO NNPDF2.3 LO G. AAD et al. PHYS. REV. D 104, 112005 (2021) 112005-4 algorithms as the data, and are weighted to match the observed distribution of the pileup in data. Dedicated correction factors are applied to simulation to account for differences in efficiencies and energy calibrations between recorded data and simulations. In this analysis, data-driven methods are applied that improve the modeling of the dominant SM background processes by normalizing their contributions to data. These are described in Sec. VI. The production of top-quark pairs, with or without an associatedHiggsboson,andofsingletopquarksinthes-ortchannel or associated with Wbosons was simulated with P OWHEG B OX [88–91], while associated production of topquark pairs and a vector boson V¼Wor Z,aswellastopquark production in other processes (later called “other top”) giving smaller contributions (t¯ tþWW,t¯ tþWZ,tWZ,tZ, t¯ tt and t¯ tt¯ t), was simulated with M AD G RAPH 5_aMC@NLO [104]. The events were interfaced to P YTHIA [92] to model the parton shower, hadronization, and underlying event, using the NNPDF2.3 LO set of PDFs [86]. The production of singlevector boson (Vþjets), diboson (VV) and triboson (VVV) events was simulated with S HERPA using the NNPDF3.0 NLO PDF set [94]. Stop-stau signal samples were produced for various values of mð˜ tÞand mð˜τÞ. The pair production of top squarks was simulated at leading order with up to two additional partons in M AD G RAPH 5_aMC@NLO. For the decays of the SUSY particles, the top squark and the tau slepton, M AD S PIN [111] was used to preserve spin correlation and finite-width effects. Both decays are assumed to be prompt; i.e., the SUSY particles have a negligible lifetime. The subsequent decays as well as the hadronization were simulated in P YTHIA . Cross sections are calculated including approximate next-to-next-to-leading-order (NNLO) supersymmetric quantum chromodynamics (QCD) corrections, with resummation of next-to-next-toleading logarithmic (NNLL) soft gluon terms [107–110]. The matching of matrix element and parton shower was done with the CKKW-L prescription [112,113], with the matching scale set to one quarter of the top-squark mass. Simulated events with pair production of upor downtype scalar third-generation leptoquarks LQu=d 3were generated at next-to-leading order (NLO) in QCD with M AD G RAPH 5_aMC@NLO, using the LQ model of Ref. [114] that adds parton showers to previous fixed-order NLO QCD calculations [115,116], and the NNPDF3.0 NLO parton distribution function set with αsðmZÞ¼0.118. M AD S PIN was used for the prompt decays of the leptoquarks into spin-entangled quark-lepton pairs of the third generation. Parton showering and hadronization were simulated in P YTHIA with the NNPDF2.3 LO PDF set with αsðmZÞ¼0.130. The couplings in the Yukawa-type interaction of the leptoquarks with the quark-lepton pair are determined by two parameters: a common coupling strength λand an additional parameter β, with the coupling to a quark and a charged lepton given by ffiffiffi β pλ, and the coupling to a quark and a neutrino by ffiffiffiffiffiffiffiffiffiffiffi 1−β pλ. The branching fraction BðLQu=d 3→qlÞinto a quark and a charged lepton is, except for kinematic effects arising from the mass differences of the decay products, equal to β. The leptoquark signal samples were generated for various leptoquark masses mðLQu=d 3Þ and with a fixed parameter value of β¼0.5, so that both decays of the leptoquarks, either into a quark and a neutrino or into a quark and a charged lepton, were possible. These events can be reweighted to arbitrary branching fractions BðLQu=d 3→qlÞto derive the interpretation of the analysis results in the plane of mðLQu=d 3Þvs BðLQu=d 3→qlÞ.The coupling parameter λwas set to 0.3, close to the numeric value of the electromagnetic coupling e¼ffiffiffiffiffiffiffiffi 4πα p, resulting in a LQu=d 3width equal to about 0.2% of its mass [60,117]. The cross sections for direct top-squark pair production are used for LQu=d 3pair production, as both involve massive, scalar, color-charged particles and the production modes are the same. These cross sections do not include the lepton t-channel contributions possible for LQ pair production, which are also neglected in Ref. [114] and may lead to corrections at the percent level [118]. Simulated events with pair production of thirdgeneration vector leptoquarks LQv 3were generated at leading order in QCD with M AD G RAPH 5_aMC@NLO, using the LQ model of Ref. [119] and the NNPDF3.0 NLO parton distribution function set with αsðmZÞ¼0.118. M AD S PIN was used for the prompt decays of the leptoquarks, and parton showering and hadronization were simulated in P YTHIA with the NNPDF2.3 LO PDF set with αsðmZÞ¼0.130. The LQv 3in this model corresponds to the U1state in the BRW classification [60] and carries an electric charge of QðLQv 3Þ¼þ2 3e. The model includes two additional vector states that are needed to obtain a realistic extension of the SM, a color singlet Z0and a color octet G0. However, the Z0and G0do not appear in the Feynman diagrams considered for pair production of vector leptoquarks, as their interactions with the vector leptoquarks are not included in the model. All βparameters are set to zero except for β33 L, such that only decays to left-chiral fermion fields are allowed, for which the coupling strength is set to gU¼3.0. The large value of gUis motivated by a suppression of the production cross section for additional mediators in a ultraviolet completion of the model, which might otherwise be in tension with LHC limits if these mediators are as light as needed to be consistent with the range of LQ masses considered here. As no higher-order computations of the cross sections are available for this vector-leptoquark model, the leading-order cross sections computed by the event generator are used. Two different scenarios are considered: the minimal-coupling scenario with κU¼˜ κU¼1, where the LQ couples to the SM gauge bosons purely through the covariant derivative, and the Yang–Mills scenario with κU¼˜ κU¼0, where the LQ is SEARCH FOR NEW PHENOMENA IN PP COLLISIONS IN …PHYS. REV. D 104, 112005 (2021) 112005-5 a massive gauge boson and has additional couplings to the SM gauge bosons [120]. The two scenarios differ mainly in the pair-productioncross section, which is roughly 5 timesas large in the Yang–Mills scenario at mðLQv 3Þ¼1.5TeV as in the minimal-coupling scenario, which in turn is roughly 4 times as large as the pair-production cross section for the scalar LQu=d 3at the same mass. IV. EVENT RECONSTRUCTION All events are required to have at least one reconstructed interaction vertex with a minimum of two associated tracks with pT>500 MeV. In events with multiple vertices, the one with the highest sum of squared transverse momenta of associated tracks is chosen as the primary vertex [121]. Events that contain jets that do not satisfy the set of quality criteria described in Ref. [122] are rejected in order to reduce noncollision backgrounds and backgrounds induced by calorimeter noise. Jets are reconstructed from particle-flow objects [123] calibrated at the EM scale using the anti-ktalgorithm with a radius parameter of R¼0.4[124,125]. Since both signal models predict the production of particles with large masses, only jets in the central region within jηj<2.8 are used. The jets are calibrated following the procedure described in Ref. [126] and are required to have pT>20 GeV. To suppress jets from pileup interactions, jet candidates with pT<60 GeV and jηj<2.4are required to pass the tight working point of the jet vertex tagger [127]. Selected jets that are likely to originate from the hadronization of a bottom quark are flagged as b-jets if they lie within jηj<2.5and are tagged by the DL1r algorithm, a multivariate discriminant based on various inputs such as track impact parameters and displaced secondary vertices [128,129].Theb-tagging algorithm uses a working point with an efficiency of 77%, with an approximate misidentification probability of 20% for jets arising from charm quarks, 6.7% for hadronically decaying τ-leptons, and 0.9% for light-flavor jets in simulated t¯ tevents. Tau leptons which decay leptonically are not identified as such, but are instead reconstructed as a candidate for a prompt electron or muon. Therefore, in the context of reconstructed analysis objects, “tau lepton”will always refer to a hadronic tau lepton, i.e., a tau lepton that decays hadronically. The visible component of hadronically decaying tau leptons is reconstructed from anti-ktjets (R¼0.4) built from locally calibrated topological clusters [130], with a distance parameter R¼0.4and requiring pT>10 GeV and jηj<2.5[131,132]. The energy calibration applies a pileup subtraction and a correction to the detector response. Information from the tracking system improves the energy resolution at low pT[132,133]. Taulepton candidates are required to have pT>20 GeV and lie outside the transition region 1.37 <jηj<1.52 between the barrel and end cap calorimeters. Furthermore, they must have either one or three charged tracks (“prongs”) with a charge sum of 1in units of the elementary charge. A recurrent neural network algorithm [134] distinguishes hadronically decaying tau leptons from quarkand gluoninitiated jets by using a combination of high-level discriminating variables as well as tracking and calorimeter measurements. Its medium working point is used to identify hadronic tau leptons, with efficiencies of 75% and 60% in simulated Drell-Yan events, and background-rejection factors of 35 and 240 in simulated dijet events, for one-prong and three-prong decays, respectively. Electrons misidentified as hadronic tau-lepton candidates are rejected using a dedicated boosted decision tree algorithm. Reconstructed tau leptons in simulated events are called “real”tau leptons if they can be geometrically matched to a tau lepton in the MC “truth”record; otherwise they are referred to as “fake” tau leptons. As described in Sec. V, events with prompt electrons or muons are rejected in the analysis selections, so these only enter in the computation of missing transverse momentum and in the overlap-removal procedure, and are not considered otherwise. Electron candidates are reconstructed from energy deposits in the electromagnetic calorimeter that are matched to tracks in the inner detector (ID) [135,136]. They are required to have pT>10 GeV and jηj<2.47 and pass the LooseAndBLayer identification requirement. Muon candidates are reconstructed by combining information from the ID and the muon spectrometer [137]. They are required to have pT>10 GeV and jηj<2.7and satisfy the medium identification criteria. The absolute value of the longitudinal impact parameter z0of each prompt electron or muon candidate is required to be less than 0.5 mm. An overlap-removal procedure is applied to all selected objects to resolve ambiguities in the reconstruction in several consecutive steps. First, if two electrons share the same track, the electron with lower transverse momentum is discarded. Next, tau leptons overlapping with an electron or a muon within ΔRy<0.2are removed, where the angular distance is measured in units of ΔRy≡ ffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi ðΔyÞ2þðΔϕÞ2 pwith the rapidity yinstead of the pseudorapidity ηto account for cases where particle masses cannot be neglected. If an electron shares an ID track with a muon, the electron is discarded unless the muon is tagged as a minimum-ionizing particle in the calorimeter, in which case the muon is discarded. Jets within ΔRy¼0.2of an electron are removed. In order to suppress electrons from semileptonic heavy-flavor decays, electrons within ΔRy¼0.4of a jet are removed. Any jet with fewer than three associated tracks is discarded if a muon is within ΔRy¼0.2of the jet or if a muon can be matched to a track associated with the jet. For the same reason as for electrons, muons within ΔRy¼0.4of a jet are removed. Lastly, jets within ΔRy¼0.4of a tau lepton are removed. The missing transverse momentum Emiss Tis defined as the negative vector sum of the transverse momenta of all calibrated objects mentioned above, photons [136], and an G. AAD et al. PHYS. REV. D 104, 112005 (2021) 112005-6 additional soft term including all tracks associated with the primary vertex but not matched to any reconstructed object [138,139]. The magnitude of Emiss Tis denoted by Emiss T. V. EVENT SELECTION The analysis covers two different channels: the singletau channel and the di-tau channel. In both channels, object multiplicities and kinematic variables are used to define several different event selections (analysis regions). All of these event selections start from a common preselection described below. The preselections in the single-tau and ditau channels are identical except for the number of tau leptons and b-tagged jets. The sets of events selected in the two channels are thus mutually exclusive and can therefore be statistically combined, as is done in the interpretation of the results. A. Preselection The preselection requirements for the two channels are summarized in Table II. Events are selected using an Emiss T trigger [75]. In combination with the requirement of Emiss T>250 GeV, this trigger is fully efficient in the phase space that the analysis targets. As no light leptons are expected from the benchmark signal models when only hadronically decaying tau leptons are considered, events with light leptons are rejected. Events are required to have at least two jets, at least one (two) of which must be b-tagged in the di-tau (single-tau) channel. Additionally, events in the di-tau channel are required to have at least two reconstructed tau leptons, whereas exactly one tau lepton is required in the single-tau channel. The tight Emiss Tand b-tagging requirements efficiently suppress multijet events such that their contribution to the analysis regions is negligible. This was verified with dedicated data-driven estimates for both channels. B. Signal regions Dedicated signal-enriched regions are defined for each channel, having been optimized individually by maximizing the estimated discovery significance [140] for benchmark signal models close to the previous exclusion contours. The selection requirements for the signal regions are explained in the following, and a summary is included in the overview of the analysis regions in Table III for the di-tau channel and Table IV for the single-tau channel. The signal region (SR) in the di-tau channel targets stop-stau signal models with a low to modest mass difference between the top squark and the tau slepton. This SR is not used for the leptoquark models, as the final states for that model at β¼0.5have only one tau lepton on average. The case of β¼1.0, which would yield two tau leptons, is not within the scope of this paper, and the requirements on Emiss Tand that no leptons be present in the final state strongly reduce the sensitivity to this scenario. The singletau channel employs two signal regions: a one-bin SR for the model-independent fit, and a multibin SR for the modeldependent fit, as is discussed in Sec. VIII. Each of the two signal regions in this channel is optimized simultaneously for the scalar-leptoquark signal models and the stop-stau signal models that have a large mass difference between the top squark and the tau slepton. 1. Di-tau channel The most discriminating variable in the di-tau channel is the “stransverse”mass variable [141,142], which by itself already provides good separation between the signal and the background. The stransverse mass mT2is a generalization of the transverse mass mT, which is computed as mT2ðpT;Emiss TÞ¼2pTEmiss Tð1−cos ΔϕðpT;Emiss TÞÞ from the transverse momentum of some given particle and the missing transverse momentum. It generalizes the transverse mass for symmetric event topologies where two identical particles each decay into a visible and an invisible product. In this case the individual transverse momenta of the invisible particles can no longer be directly approximated by the measured missing transverse momentum, as the information about their individual contributions to the missing transverse momentum is lost. Using subscripts to refer to the physics objects reconstructed in a collision event in order of decreasing transverse momentum, for the two leading tau leptons, i.e., the two tau leptons with the largest (τ1) and second-largest (τ2) transverse momentum, mT2ðτ1;τ2Þis computed as mT2ðτ1;τ2Þ¼ min qa Tþqb T¼Emiss Tmax½mTðpτ1 T;qa TÞ;mTðpτ2 T;qb TÞ; where aand brefer to two invisible particles assumed to be produced with transverse momentum qa;b T. The minimum is taken over all possible assignments to qa;b Tthat sum to the measured Emiss T. The masses of the invisible particles are free parameters and are set to zero. For the dominant topquark-related backgrounds, the mT2ðτ1;τ2Þdistribution features an end point near the W-boson mass. By placing a lower bound at 70 GeV most of this background can be removed, while efficiently selecting stop-stau signal events, for which the mT2ðτ1;τ2Þdistribution exhibits a tail towards TABLE II. Preselection of the di-tau and single-tau channels. Di-tau preselection Single-tau preselection Emiss T-trigger fired and Emiss T>250 GeV No light leptons (e=μ) At least two jets At least two hadronic tau leptons Exactly one hadronic tau lepton At least one b-tagged jet At least two b-tagged jets SEARCH FOR NEW PHENOMENA IN PP COLLISIONS IN …PHYS. REV. D 104, 112005 (2021) 112005-7 much higher values. The sensitivity is further enhanced by raising the lower bound on Emiss Tto 280 GeV and requiring the two leading tau leptons to carry electric charges with opposite signs, a criterion later denoted by OSðτ1;τ2Þ¼1. 2. Single-tau channel Both signal regions in the single-tau channel have a lower bound on Emiss Tat 280 GeVand on the sum of the transverse masses of the b-jets, PmTðb1;2Þ¼mTðb1ÞþmTðb2Þ,at 700 GeV. In this expression and the following, mTðAÞfor a given particle Ashould be read as mTðAÞ≡mTðpA T;Emiss TÞ. The one-bin SR requires mTðτÞ>300 GeV and sT> 800 GeV, where sTis defined as the scalar sum of the transversemomentaofthetauleptonandthetwoleadingjets, sT¼pTðτÞþpTðjet1ÞþpTðjet2Þ. While both the stop-stau and LQu=d 3signals show fairly similar behavior in most kinematic variables, their pTðτÞdistributions differ. This is due to the large mass difference in the stop-stau target scenario,sothatthetauleptonsaresofterthanthoseproduced in the LQu=d 3decay. To account for the different shapes of the transverse momentum distributions of the tau leptons, the second SR is defined with three bins in pTðτÞ. The first two pTðτÞbins cover 50 to 100 GeVand 100 to 200 GeV, and the last bin all values beyond 200 GeV. To reduce the statistical uncertainty in the three pTðτÞbins, two selection requirements are loosened relative to the one-bin SR: the minimum mTðτÞrequirement is lowered to 150 GeV, and the minimum sTrequirement to 600 GeV. As the one-bin SR is a subset of the multibin SR, they cannot be combined in the statistical interpretationoftheresultsdiscussedinSec.VIII.Amultibin SR based on sTinstead of pTðτÞwas also tested but was found to have lower sensitivity. VI. BACKGROUND ESTIMATION The background in the signal regions is dominated by t¯ t and single-top production, which can yield events with a final state similar to the signal processes. Dedicated control regions are defined for these background processes. Topquark production can contribute to the background in different ways. Events with t¯ tproduction, where both W bosons arising from the top-quark decay into a hadronic tau lepton, have two real tau leptons. This process, denoted by t¯ t(2 real τ), contributes to the di-tau channel if both hadronic tau leptons are correctly identified. If instead only one of the Wbosons from the t¯ tsystem gives a hadronic tau lepton which is correctly identified, and the second W boson decays hadronically, the resulting jet from the second W-boson decay can be misidentified as a tau lepton, and such an event can then still satisfy the di-tau channel selection criteria. While the misidentification probability is of the order of a few percent, the larger branching fraction of hadronic Wdecays and the less pronounced end point in the mT2ðτ1;τ2Þdistribution for t¯ tevents with one real and one fake tau lepton still leads to a significant contribution in the di-tau channel. This type of event can also enter the single-tau channel selection, if the jet from the second W boson is not misidentified as a tau lepton. Di-tau t¯ tevents in which only one of the two identified tau leptons is real, and single-tau t¯ tevents with one real tau lepton, are referred to as t¯ t(1 real τ) events. Lastly, fully hadronic t¯ tdecays, without any real tau leptons that pass the selections in either the single-tau or di-tau channel, are referred to as t¯ t-fake events. Due to their different kinematics, the simulated t¯ t TABLE III. Definitions of the t¯ tcontrol and validation regions and the signal region in the di-tau channel. Centered dots () signify that no requirement on the givenvariable is applied, while brackets indicate an allowed range for the variable. These requirements extend those of the di-tau preselection from Table II. Variable CR t¯ t(2 real τ)CRt¯ t(1 real τ)VRt¯ t(2 real τ)VRt¯ t(1 real τ)SR Emiss T    >280 GeV OSðτ1;τ2Þ1 1 1 mT2ðτ1;τ2Þ<35 GeV <35 GeV ½35;70GeV ½35;70GeV >70 GeV mvisðτ1;τ2Þ>50 GeV >50 GeV    mTðτ1Þ>50 GeV <50 GeV >70 GeV <70 GeV  FIG. 2. Overview of the selections defining the control, validation and signal regions in the di-tau channel in the phase-space spanned by the variables mT2ðτ1;τ2Þ,mTðτ1Þ, and OSðτ1;τ2Þ, where OSðτ1;τ2Þ¼1means that the reconstructed charges of the two leading tau leptons have opposite signs. In addition to these variables, Emiss T>280 GeV is required for the signal region, and mvisðτ1;τ2Þ>50 GeV for the control regions. The complete definitions are summarized in Table III. G. AAD et al. PHYS. REV. D 104, 112005 (2021) 112005-8 events are separated into these three event types, t¯ t(2 real τ), t¯ t(1 real τ), and t¯ t-fake, and treated as separate background components in the following. Subdominant contributions to the SM background arise from singly produced vector bosons (Wþjets and Zþjets events) and production of vector bosons in association with top-quark pairs (t¯ tþV). In addition, multiboson production, t¯ tproduction in association with a Higgs boson (t¯ tþH) and other top-related processes yield small contributions. These subdominant processes are normalized according to the theory cross section predictions and the integrated luminosity measured in data. The normalization factors for the MC predictions for t¯ t and single-top production are extracted in a simultaneous binned maximum-likelihood fit to the observed data in the control regions (CRs). This fit, where no signal contributions are included, is referred to as the background-only fit. The CRs are designed to be enriched in a given background process and to be kinematically as similar to the SRs as possible, while maintaining sufficient purity and a high enough event yield with negligible contamination from signal. In addition to the data yields in the CRs, the expected yields and statistical and systematic uncertainties from MC simulation, described in Sec. VII, are input to the background-only fit. The yields obtained from the background-only fit can then be extrapolated to dedicated validation regions (VRs) to assess the accuracy of the background estimate. All CR, VR and SR selections are mutually exclusive so that they are statistically independent as required for the fit. The CR and VR selections are 0 20 40 60 80 100 120 140 160 Entries / 7 GeV Di-tau channel )τ (2 real t CR t ATLAS -1 = 13 TeV, 139 fbs Data Total SM )τ (2 real t t )τ (1 real t t V+jets Other Single top 0 5 10 15 20 25 30 35 ) [GeV] 2 τ, 1 τ( T2 m 0.5 1 1.5 Data / SM 0 5 10 15 20 25 Entries / 11.7 GeV Di-tau channel )τ (2 real t VR t ATLAS -1 = 13 TeV, 139 fbs Data Total SM )τ (2 real t t )τ (1 real t t Other V+jets Single top 35 40 45 50 55 60 65 70 ) [GeV] 2 τ, 1 τ( T2 m 0.5 1 1.5 Data / SM 0 20 40 60 80 100 120 140 Entries / 50 GeV Di-tau channel )τ (1 real t CR t ATLAS -1 = 13 TeV, 139 fbs Data Total SM )τ (1 real t t )τ (2 real t t V+jets Other Single top 250 300 350 400 450 500 550 [GeV] miss T E 0.5 1 1.5 Data / SM 0 10 20 30 40 50 Entries / 100 GeV Di-tau channel )τ (1 real t VR t ATLAS -1 = 13 TeV, 139 fbs Data Total SM )τ (1 real t t )τ (2 real t t V+jets Single top Other 250 300 350 400 450 500 550 [GeV] miss T E 0.5 1 1.5 Data / SM FIG. 3. Distributions of mT2ðτ1;τ2Þand Emiss Tin the di-tau channel. The left-hand plots show the control regions and the right-hand plots the validation regions, with mT2ðτ1;τ2Þin the t¯ t(2 real τ) CR and VR in the top row and Emiss Tin the t¯ t(1 real τ) CR and VR in the bottom row. The CRs and VRs have different requirements on the transverse mass mTðτ1Þ. The stacked histograms show the various SM background contributions. The hatched band indicates the total statistical and systematic uncertainty of the SM background. The t¯ t (2 real τ) and t¯ t(1 real τ) contributions and the single-top background contributions are scaled with the normalization factors obtained from the background-only fit. Minor backgrounds are grouped together and denoted by “Other”. This includes t¯ t-fake, t¯ tþX, multiboson, and other top. The rightmost bin includes the overflow. SEARCH FOR NEW PHENOMENA IN PP COLLISIONS IN …PHYS. REV. D 104, 112005 (2021) 112005-9 cross section is larger by a factor of about 40 compared to the cross section at mðLQÞ¼1250 GeV, corresponding to the excluded LQ mass at BðLQu=d 3→qlÞ¼0.5. The exclusion contours from the interpretation of the analysis results for the vector-leptoquark models are shown in the two plots in Fig. 10. As in the scalar-leptoquark case, the model-dependent fit includes, besides the four CRs, only the single-tau multibin SR. For intermediate values of the branching fraction BðLQv 3→bτÞ, the expected and observed exclusion contours at the 95% confidence level extend to masses around 1.5 TeV in the minimal-coupling scenario and to masses around 1.8 TeV in the Yang–Mills scenario. As expected, the shape of the contours as a function of BðLQv 3→bτÞis very similar to that for the scalar-leptoquark models, and the larger cross sections for the pair production of vector leptoquarks lead to a larger mass reach. In addition to the model-dependent interpretations for the signal models shown above, model-independent statements about the presence of physics that is not included in the background expectation for SM processes can also be derived from the analysis results. The model-independent fit is performed for each of the one-bin SRs of the two analysis channels separately. As no specific model is assumed, the contamination of the CRs by a potential signal is neglected, and a generic signal of variable strength is included in the SR. Table VII states the observed and expected upper limits, S95 obs and S95 exp, on the number of signal events at the 95% confidence level based on the CLs prescription, where the test statistic is evaluated using pseudoexperiments. These upper limits are also expressed as upper limits on the visible signal cross section hAϵσi95 obs, which is defined as the product of acceptance A, reconstruction efficiency ϵand signal cross section σ. The table also reports the CLbvalue, i.e., the confidence level observed for the background-only hypothesis, the discovery p-value, defined as the probability to find 600 800 1000 1200 1400 1600 ) [GeV] 1 t ~ m( 0 200 400 600 800 1000 1200 1400 1600 1800 ) [GeV] 1 τ ∼ m( ) + m(b) 1 τ ∼ ) < m( 1 t ~ m( ) exp σ1±Expected limit ( ) SUSY theory σ1±Observed limit ( (observed) -1 ATLAS 13 TeV, 36.1 fb (observed) -1 ATLAS 8 TeV, 20.3 fb LEP limit ) = 1G ~ τ→ 1 τ ∼ ) = 1, B(νb 1 τ ∼ → 1 t ~ production, with branching ratios B( 1 t ~ 1 t ~ , All limits at 95% C.L. -1 =13 TeV, 139 fbs ATLAS FIG. 8. Exclusion contours at the 95% confidence level (C.L.) for the stop-stau signal model as a function of the masses of the top squark mð˜ tÞand the tau slepton mð˜τÞ. Expected and observed limits are shown for the present search in comparison with observed limits from previous ATLAS analyses based on data from run 1 of the LHC at ffiffiffi s p¼8TeV [57] and on a partial dataset from run 2 at ffiffiffi s p¼13 TeV [58]. The green band indicates the lower limit on the mass of the tau slepton (for a massless LSP) from the LEP experiments [152]. 400 600 800 1000 1200 1400 1600 1800 2000 ) [GeV] 3 u m(LQ 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 )τ b→ 3 u B(LQ ) exp σ1±Expected limit ( ) theory σ1±Observed limit ( -1 ATLAS 13 TeV, 36.1 fb (observed) τ ν / tτ b→ 3 u production, LQ 3 u LQ 3 u LQ -1 =13 TeV, 139 fbs All limits at 95% C.L. ATLAS 400 600 800 1000 1200 1400 1600 1800 2000 ) [GeV] 3 d m(LQ 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 )τ t→ 3 d B(LQ ) exp σ1±Expected limit ( ) theory σ1±Observed limit ( -1 ATLAS 13 TeV, 36.1 fb (observed) τ ν / bτ t→ 3 d production, LQ 3 d LQ 3 d LQ -1 =13 TeV, 139 fbs All limits at 95% C.L. ATLAS FIG. 9. Expected and observed exclusion contours at the 95% confidence level (C.L.) for the third-generation scalarleptoquark signal model, as a function of the mass mðLQu=d 3Þ and the branching fraction BðLQu=d 3→qlÞinto a quark and a charged lepton. The top plot shows the exclusion contour for uptype leptoquarks LQu 3with charge þ2 3e, the bottom plot the exclusion contour for down-type leptoquarks LQd 3with charge −1 3e. The limits are derived from the binned single-tau signal region. Shown in gray for comparison are the observed exclusionlimit contours from the previous ATLAS publication that targets the same leptoquark models but is based on a subset of the run-2 data [61]. In that publication, five different analyses were considered that target not only the final state studied here but also the final states that correspond to a branching fraction BðLQu=d 3→qlÞof 0 or 1, leading to the concave shapes of the gray exclusion contours. G. AAD et al. PHYS. REV. D 104, 112005 (2021) 112005-16 the observed number of events or more under the background-only hypothesis, and the equivalent significance for each of the two channels. IX. CONCLUSION In this paper, a search for new phenomena in final states with hadronically decaying tau leptons, b-jets and large missing transverse momentum is presented. This signature provides sensitivity to models in which the new particles preferentially decay into third-generation Standard Model particles. The analysis exploits the full dataset recorded with the ATLAS detector in run 2 of the LHC, corresponding to 139 fb−1of proton–proton collisions at ffiffiffi s p¼13 TeV. No significant excess of events is observed over the Standard Model expectation. The results are thus interpreted in terms ofexclusionlimitsat95%confidencelevelfortwosimplified models with pair production of supersymmetric top squarks or leptoquarks which are assumed to only decay into thirdgeneration fermions. In the case of the supersymmetric model, masses up to 1.4 TeV are excluded for top squarks decaying via tau sleptons into nearly massless gravitinos across a wide range of tau-slepton masses. For both up-type and down-type scalar leptoquarks, masses up to about 1.25 TeV can be excluded. For vector leptoquarks with minimal couplings, masses up to about 1.5 TeV can be excluded, and up to about 1.8 TeV for vector leptoquarks with additional couplings to gauge bosons. The larger dataset, updated reconstruction and identification algorithms for tau leptons and b-jets, and theoptimized analysis strategy yield significantly better sensitivity than in earlier LHC studies. Based on the considered benchmark models, the search yields the strongest mass limits to date on pairproduced top squarks and on pair-produced third-generation scalar and vector leptoquarks at intermediate values of the branching fraction into a quark and a charged lepton. ACKNOWLEDGMENTS We thank CERN for the very successful operation of the LHC, as well as the support staff from our institutions without whom ATLAS could not be operated efficiently. We acknowledge the support of ANPCyT, Argentina; YerPhI, Armenia; ARC, Australia; BMWFW and FWF, Austria; ANAS, Azerbaijan; SSTC, Belarus; CNPq and FAPESP, Brazil; NSERC, NRC and CFI, Canada; CERN; ANID, Chile; CAS, MOSTand NSFC, China; Minciencias, Colombia; MSMT CR, MPO CR and VSC CR, Czech 400 600 800 1000 1200 1400 1600 1800 2000 ) [GeV] v 3 m(LQ 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 )τ b→ v 3 B(LQ ) exp σ1±Expected limit ( ) theory σ1±Observed limit ( τ ν / tτb→ v 3 production (minimal-coupling scenario), LQ v 3 LQ v 3 LQ , All limits at 95% C.L. -1 =13 TeV, 139 fbs ATLAS 400 600 800 1000 1200 1400 1600 1800 2000 ) [GeV] v 3 m(LQ 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 )τ b→ v 3 B(LQ ) exp σ1±Expected limit ( ) theory σ1±Observed limit ( τ ν / tτb→ v 3 Mills scenario), LQ− production (Yang v 3 LQ v 3 LQ , All limits at 95% C.L. -1 =13 TeV, 139 fbs ATLAS FIG. 10. Expected and observed exclusion contours at the 95% confidence level (C.L.) for the third-generation vectorleptoquark signal model, as a function of the mass mðLQv 3Þand the branching fraction BðLQv 3→bτÞinto a quark and a charged lepton. The top plot shows the exclusion contour for the minimalcoupling scenario, the bottom plot the exclusion contour for vector leptoquarks in the Yang–Mills scenario. The limits are derived from the binned single-tau signal region. TABLE VII. From left to right: upper limits at the 95% confidence level (C.L.) on the visible cross section (hAϵσi95 obs) and on the number of signal events (S95 obs). The third column (S95 exp) shows the upper limit at the 95% C.L. on the number of signal events, given the expected number (and 1σexcursions of the expectation) of background events. The last two columns indicate the confidence level observed for the background-only hypothesis (CLb), the discovery p-value (pðs¼0Þ) and the significance (Z). In the di-tau SR, where fewer events are observed than predicted by the fitted background estimate, the p-value is capped at 0.5. Analysis region hAϵσi95 obs [fb] S95 obs S95 exp CLbpðs¼0ÞZ Di-tau SR 0.03 4.1 5.3þ2.2 −1.50.18 0.50 0.0 Single-tau one-bin SR 0.06 8.2 5.1þ2.1 −1.30.91 0.08 1.37 SEARCH FOR NEW PHENOMENA IN PP COLLISIONS IN …PHYS. REV. D 104, 112005 (2021) 112005-17 Republic; DNRF and DNSRC, Denmark; IN2P3-CNRS and CEA-DRF/IRFU, France; SRNSFG, Georgia; BMBF, HGF and MPG, Germany; GSRI, Greece; RGC and Hong Kong SAR, China; ISF and Benoziyo Center, Israel; INFN, Italy; MEXT and JSPS, Japan; CNRST, Morocco; NWO, Netherlands; RCN, Norway; MNiSW and NCN, Poland; FCT, Portugal; MNE/IFA, Romania; JINR; MES of Russia and NRC KI, Russian Federation; MESTD, Serbia; MSSR, Slovakia; ARRS and MIZŠ, Slovenia; DSI/NRF, South Africa; MICINN, Spain; SRC and Wallenberg Foundation, Sweden; SERI, SNSF and Cantons of Bern and Geneva, Switzerland; MOST, Taiwan; TAEK, Turkey; STFC, United Kingdom; DOE and NSF, United States of America. In addition, individual groups and members have received support from BCKDF, CANARIE, Compute Canada and CRC, Canada; COST, ERC, ERDF, Horizon 2020 and Marie Skłodowska-Curie Actions, European Union; Investissements d’Avenir Labex, Investissements d’Avenir Idex and ANR, France; DFG and AvH Foundation, Germany; Herakleitos, Thales and Aristeia programmes co-financed by EU-ESF and the Greek NSRF, Greece; BSF-NSF and GIF, Israel; Norwegian Financial Mechanism 2014-2021, Norway; La Caixa Banking Foundation, CERCA Programme Generalitat de Catalunya and PROMETEO and GenT Programmes Generalitat Valenciana, Spain; Göran Gustafssons Stiftelse, Sweden; The Royal Society and Leverhulme Trust, United Kingdom. The crucial computing support from all WLCG partners is acknowledged gratefully, in particular from CERN, the ATLAS Tier-1 facilities at TRIUMF (Canada), NDGF (Denmark, Norway, Sweden), CC-IN2P3 (France), KIT/GridKA (Germany), INFN-CNAF (Italy), NL-T1 (Netherlands), PIC (Spain), ASGC (Taiwan), RAL (UK) and BNL (USA), the Tier-2 facilities worldwide and large non-WLCG resource providers. Major contributors of computing resources are listed in Ref. [153]. [1] Y. Golfand and E. Likhtman, Extension of the algebra of poincare group generators and violation of P invariance, Pis’ma Zh. Eksp. Teor. Fiz. 13, 452 (1971) [JETP Lett. 13, 323 (1971)], http://jetpletters.ru/ps/1584/article_24309 .pdf. [2] D. Volkov and V. Akulov, Is the neutrino a goldstone particle?, Phys. Lett. 46B, 109 (1973). [3] J. Wess and B. Zumino, Supergauge transformations in four dimensions, Nucl. Phys. B70, 39 (1974). [4] J. Wess and B. Zumino, Supergauge invariant extension of quantum electrodynamics, Nucl. Phys. B78, 1 (1974). [5] S. Ferrara and B. Zumino, Supergauge invariant YangMills theories, Nucl. Phys. B79, 413 (1974). [6] A. Salam and J. Strathdee, Super-symmetry and nonAbelian gauges, Phys. Lett. 51B, 353 (1974). [7] S. P. Martin, A supersymmetry primer, Adv. Ser. Dir. High Energy Phys. 18, 1 (1998). [8] N. Sakai, Naturalness in supersymmetric GUTS, Z. Phys. C11, 153 (1981). [9] S. Dimopoulos, S. Raby, and F. Wilczek, Supersymmetry and the scale of unification, Phys. Rev. D 24, 1681 (1981). [10] L. E. Ibáñez and G. G. Ross, Low-energy predictions in supersymmetric grand unified theories, Phys. Lett. 105B, 439 (1981). [11] S. Dimopoulos and H. Georgi, Softly broken supersymmetry and SU(5), Nucl. Phys. B193, 150 (1981). [12] G. R. Farrar and P. Fayet, Phenomenology of the production, decay, and detection of new hadronic states associated with supersymmetry, Phys. Lett. 76B, 575 (1978). [13] H. Goldberg, Constraint on the Photino Mass from Cosmology, Phys. Rev. Lett. 50, 1419 (1983);103, 099905(E) (2009). [14] J. Ellis, J. Hagelin, D. V. Nanopoulos, K. A. Olive, and M. Srednicki, Supersymmetric relics from the big bang, Nucl. Phys. B238, 453 (1984). [15] W. De Boer, Grand unified theories and supersymmetry in particle physics and cosmology, Prog. Part. Nucl. Phys. 33, 201 (1994). [16] H. Georgi and S. Glashow, Unity of All ElementaryParticle Forces, Phys. Rev. Lett. 32, 438 (1974). [17] E. Farhi and L. Susskind, Technicolour, Phys. Rep. 74, 277 (1981). [18] B. Schrempp and F. Schrempp, Light leptoquarks, Phys. Lett. 153B, 101 (1985). [19] V. D. Angelopoulos, J. Ellis, H. Kowalski, D. V. Nanopoulos, N. D. Tracas, and F. Zwirner, Search for new quarks suggested by the superstring, Nucl. Phys. B292, 59 (1987). [20] W. Buchmüller and D. Wyler, Constraints on SU(5)-type leptoquarks, Phys. Lett. B 177, 377 (1986). [21] R. Barbier et al., R-parity-violating supersymmetry, Phys. Rep. 420, 1 (2005). [22] G. Hiller and M. Schmaltz, RKand future b→sll physics beyond the standard model opportunities, Phys. Rev. D 90, 054014 (2014). [23] B. Gripaios, M. Nardecchia, and S. A. Renner, Composite leptoquarks and anomalies in B-meson decays, J. High Energy Phys. 05 (2015) 006. [24] M. Freytsis, Z. Ligeti, and J. T. Ruderman, Flavor models for ¯ B→DðÞτ¯ ν,Phys. Rev. D 92, 054018 (2015). [25] M. Bauer and M. Neubert, Minimal Leptoquark Explanation for the RDðÞ,RK, and ðg−2ÞμAnomalies, Phys. Rev. Lett. 116, 141802 (2016). G. AAD et al. PHYS. REV. D 104, 112005 (2021) 112005-18 [26] L. Di Luzio and M. Nardecchia, What is the scale of new physics behind the B-flavour anomalies?, Eur. Phys. J. C 77, 536 (2017). [27] D. Buttazzo, A. Greljo, G. Isidori, and D. Marzocca, Bphysics anomalies: A guide to combined explanations, J. High Energy Phys. 11 (2017) 044. [28] J. M. Cline, B decay anomalies and dark matter from vectorlike confinement, Phys. Rev. D 97, 015013 (2018). [29] BABAR Collaboration, Measurement of an excess of ¯ B→ DðÞτ−¯ ντdecays and implications for charged Higgs bosons, Phys. Rev. D 88, 072012 (2013). [30] Belle Collaboration, Measurement of the branching ratio of ¯ B→DðÞτ−¯ ντrelative to ¯ B→DðÞl−¯ νldecays with hadronic tagging at Belle, Phys. Rev. D 92, 072014 (2015). [31] LHCb Collaboration, Measurement of the Ratio of Branching Fractions Bð¯ B0→Dþτ−¯ ντÞ=Bð¯ B0→Dþμ−¯ νμÞ,Phys. Rev. Lett. 115, 111803 (2015);115, 159901(E) (2015). [32] Belle Collaboration, Measurement of the τLepton Polarization and RðDÞin the Decay ¯ B→Dτ−¯ ντ,Phys. Rev. Lett. 118, 211801 (2017). [33] LHCb Collaboration, Measurement of the Ratio of Branching Fractions BðBþ c→J=ψτþντÞ=BðBþ c→J=ψμþνμÞ, Phys. Rev. Lett. 120, 121801 (2018). [34] LHCb Collaboration, Angular analysis of the B0→ K0μþμ−decay using 3fb−1of integrated luminosity, J. High Energy Phys. 02 (2016) 104. [35] Belle Collaboration, Lepton-Flavor-Dependent Angular Analysis of B→Klþl−,Phys. Rev. Lett. 118, 111801 (2017). [36] LHCb Collaboration, Test of lepton universality with B0→ K0lþl−decays, J. High Energy Phys. 08 (2017) 055. [37] LHCb Collaboration, Test of lepton universality in beautyquark decays, arXiv:2103.11769. [38] E. C. Leskow, G. D’Ambrosio, A. Crivellin, and D. Müller, ðg−2Þμ, lepton flavor violation, and Zdecays with leptoquarks: Correlations and future prospects, Phys. Rev. D 95, 055018 (2017). [39] D. Chakraverty, D. Choudhury, and A. Datta, A nonsupersymmetric resolution of the anomalous muon magnetic moment, Phys. Lett. B 506, 103 (2001). [40] Muon g—2 Collaboration, Measurement of the Positive Muon Anomalous Magnetic Moment to 0.46 ppm, Phys. Rev. Lett. 126, 141801 (2021). [41] M. Dine and W. Fischler, A phenomenological model of particle physics based on supersymmetry, Phys. Lett. 110B, 227 (1982). [42] L. Alvarez-Gaum´e, M. Claudson, and M. B. Wise, Lowenergy supersymmetry, Nucl. Phys. B207, 96 (1982). [43] C. R. Nappi and B. A. Ovrut, Supersymmetric extension of the SU(3) x SUð2Þ×Uð1Þmodel, Phys. Lett. 113B, 175 (1982). [44] M. Asano, H. D. Kim, R. Kitano, and Y. Shimizu, Natural supersymmetry at the LHC, J. High Energy Phys. 12 (2010) 019. [45] K. Inoue, A. Kakuto, H. Komatsu, and S. Takeshita, Aspects of grand unified models with softly broken supersymmetry, Prog. Theor. Phys. 68, 927 (1982);70, 330(E) (1983). [46] J. R. Ellis and S. Rudaz, Search for supersymmetry in toponium decays, Phys. Lett. B 128, 248 (1983). [47] J. Alwall, M.-P. Le, M. Lisanti, and J. G. Wacker, Searching for directly decaying gluinos at the Tevatron, Phys. Lett. B 666, 34 (2008). [48] J. Alwall, P. Schuster, and N. Toro, Simplified models for a first characterization of new physics at the LHC, Phys. Rev. D 79, 075020 (2009). [49] D. Alves et al., Simplified models for LHC new physics searches, J. Phys. G 39, 105005 (2012). [50] ATLAS Collaboration, Search for a scalar partner of the top quark in the all-hadronic t¯ tplus missing transverse momentum final state at ffiffiffi s p¼13 TeV with the ATLAS detector, Eur. Phys. J. C 80, 737 (2020). [51] ATLAS Collaboration, Search for new phenomena with top quark pairs in final states with one lepton, jets, and missing transverse momentum in pp collisions at ffiffiffi s p¼ 13 TeV with the ATLAS detector, J. High Energy Phys. 04 (2021) 174. [52] ATLAS Collaboration, Search for new phenomena in events with two opposite-charge leptons, jets and missing transverse momentum in pp collisions at ffiffiffi s p¼13 TeV with the ATLAS detector, J. High Energy Phys. 04 (2021) 165. [53] CMS Collaboration, Search for top squark production in fully-hadronic final states in proton–proton collisions at ffiffiffi s p¼13 TeV, Phys. Rev. D 104, 052001 (2021). [54] CMS Collaboration, Search for direct top squark pair production in events with one lepton, jets, and missing transverse momentum at 13 TeV with the CMS experiment, J. High Energy Phys. 05 (2020) 032. [55] CMS Collaboration, Search for top squark pair production using dilepton final states in pp collision data collected at ffiffiffi s p¼13 TeV, Eur. Phys. J. C 81, 3 (2021). [56] CMS Collaboration, Combined searches for the production of supersymmetric top quark partners in proton-proton collisions at ffiffiffi s p¼13 TeV, Eur. Phys. J. C 81, 970 (2021). [57] ATLAS Collaboration, Search for direct top squark pair production in final states with two tau leptons in pp collisions at ffiffiffi s p¼8TeV with the ATLAS detector, Eur. Phys. J. C 76, 81 (2016). [58] ATLAS Collaboration, Search for top squarks decaying to tau sleptons in pp collisions at ffiffiffi s p¼13 TeV with the ATLAS detector, Phys. Rev. D 98, 032008 (2018). [59] CMS Collaboration, Search for top squark pair production in a final state with two tau leptons in proton–proton collisions at ffiffiffi s p¼13 TeV, J. High Energy Phys. 02 (2020) 015. [60] W. Buchmüller, R. Rückl, and D. Wyler, Leptoquarks in lepton—quark collisions, Phys. Lett. B 191, 442 (1987); 448, 320(E) (1999). [61] ATLAS Collaboration, Searches for third-generation scalar leptoquarks in ffiffiffi s p¼13 TeV pp collisions with the ATLAS detector, J. High Energy Phys. 06 (2019) 144. [62] ATLAS Collaboration, Search for new phenomena in final states with b-jets and missing transverse momentum in ffiffiffi s p¼13 TeV pp collisions with the ATLAS detector, J. High Energy Phys. 05 (2021) 093. [63] ATLAS Collaboration, Search for pair production of thirdgeneration scalar leptoquarks decaying into a top quark and a τ-lepton in pp collisions at ffiffiffi s p¼13 TeV with the ATLAS detector, J. High Energy Phys. 06 (2021) 179. SEARCH FOR NEW PHENOMENA IN PP COLLISIONS IN …PHYS. REV. D 104, 112005 (2021) 112005-19 [64] CMS Collaboration, Search for singly and pair-produced leptoquarks coupling to third-generation fermions in proton–proton collisions at ffiffiffi s p¼13 TeV, Phys. Lett. B 819, 136446 (2021). [65] CMS Collaboration, Constraints on models of scalar and vector leptoquarks decaying to a quark and a neutrino at ffiffiffi s p¼13 TeV, Phys. Rev. D 98, 032005 (2018). [66] CMS Collaboration, Search for third-generation scalar leptoquarks decaying to a top quark and a τlepton at ffiffiffi s p¼13 TeV, Eur. Phys. J. C 78, 707 (2018). [67] CMS Collaboration, Search for Leptoquarks Coupled to Third-Generation Quarks in Proton–Proton Collisions at ffiffiffi s p¼13 TeV, Phys. Rev. Lett. 121, 241802 (2018). [68] CMS Collaboration, Search for heavy neutrinos and thirdgeneration leptoquarks in hadronic states of two τleptons and two jets in proton–proton collisions at ffiffiffi s p¼13 TeV, J. High Energy Phys. 03 (2019) 170. [69] CMS Collaboration, Search for a singly produced thirdgeneration scalar leptoquark decaying to a τlepton and a bottom quark in proton–proton collisions at ffiffiffi s p¼13 TeV, J. High Energy Phys. 07 (2018) 115. [70] ATLAS Collaboration, The ATLAS experiment at the CERN large hadron collider, J. Instrum. 3, S08003 (2008). [71] ATLAS Collaboration, ATLAS insertable B-layer: Technical design report, Report No. ATLAS-TDR-19; Report No. CERN-LHCC-2010-013, 2010, https://cds.cern.ch/ record/1291633; Addendum, Report No. ATLAS-TDR19-ADD-1; Report No. CERN-LHCC-2012-009, 2012, https://cds.cern.ch/record/1451888. [72] B. Abbott et al., Production and integration of the ATLAS Insertable B-Layer, J. Instrum. 13, T05008 (2018). [73] ATLAS Collaboration, Operation of the ATLAS trigger system in Run 2, J. Instrum. 15, P10004 (2020). [74] ATLAS Collaboration, The ATLAS Collaboration software and firmware, Report No. ATL-SOFT-PUB-2021001, 2021, https://cds.cern.ch/record/2767187. [75] ATLAS Collaboration, Performance of the missing transverse momentum triggers for the ATLAS detector during Run-2 data taking, J. High Energy Phys. 08 (2020) 080. [76] ATLAS Collaboration, ATLAS data quality operations and performance for 2015–2018 data-taking, J. Instrum. 15, P04003 (2020). [77] ATLAS Collaboration, Luminosity determination in pp collisions at ffiffiffi s p¼13 TeV using the ATLAS detector at the LHC, Report No. ATLAS-CONF-2019-021, 2019, https://cds.cern.ch/record/2677054. [78] G. Avoni et al., The new LUCID-2 detector for luminosity measurement and monitoring in ATLAS, J. Instrum. 13, P07017 (2018). [79] ATLAS Collaboration, The ATLAS simulation infrastructure, Eur. Phys. J. C 70, 823 (2010). [80] S. Agostinelli et al. ( GEANT 4Collaboration), Geant4—a simulation toolkit, Nucl. Instrum. Methods Phys. Res., Sect. A 506, 250 (2003). [81] ATLAS Collaboration, The simulation principle and performance of the ATLAS fast calorimeter simulation FastCaloSim, Report No. ATL-PHYS-PUB-2010-013, 2010, https://cds.cern.ch/record/1300517. [82] E. Bothmann et al., Event generation with S HERPA 2.2, SciPost Phys. 7, 034 (2019). [83] ATLAS Collaboration, ATLAS P YTHIA 8tunes to 7 TeV data, Report No. ATL-PHYS-PUB-2014-021, 2014, https://cds.cern.ch/record/1966419. [84] D. J. Lange, The E vt G en particle decay simulation package, Nucl.Instrum.MethodsPhys.Res.,Sect.A462,152(2001). [85] T. Sjöstrand, S. Mrenna, and P. Skands, A brief introduction to P YTHIA 8.1,Comput. Phys. Commun. 178, 852 (2008). [86] R. D. Ball et al., Parton distributions with LHC data, Nucl. Phys. B867, 244 (2013). [87] ATLAS Collaboration, The P YTHIA 8A3 tune description of ATLAS minimum bias and inelastic measurements incorporating the Donnachie–Landshoff diffractive model, Report NO. ATL-PHYS-PUB-2016-017, 2016, https://cds .cern.ch/record/2206965. [88] S. Frixione, P. Nason, and G. Ridolfi, A positive-weight next-to-leading-order Monte Carlo for heavy flavour hadroproduction, J. High Energy Phys. 09 (2007) 126. [89] P. Nason, A new method for combining NLO QCD with shower Monte Carlo algorithms, J. High Energy Phys. 11 (2004) 040. [90] S. Frixione, P. Nason, and C. Oleari, Matching NLO QCD computations with parton shower simulations: The P OWHEG method, J. High Energy Phys. 11 (2007) 070. [91] S. Alioli, P. Nason, C. Oleari, and E. Re, A general framework for implementing NLO calculations in shower Monte Carlo programs: The P OWHEG B OX ,J. High Energy Phys. 06 (2010) 043. [92] T. Sjöstrand, S. Ask, J. R. Christiansen, R. Corke, N. Desai, P. Ilten, S. Mrenna, S. Prestel, C. O. Rasmussen, and P. Z. Skands, An introduction to P YTHIA 8.2,Comput. Phys. Commun. 191, 159 (2015). [93] M. Czakon and A. Mitov, Top++: A program for the calculation of the top-pair cross-section at hadron colliders, Comput. Phys. Commun. 185, 2930 (2014). [94] R. D. Ball et al., Parton distributions for the LHC run II, J. High Energy Phys. 04 (2015) 040. [95] E. Re, Single-top Wt-channel production matched with parton showers using the P OWHEG method, Eur. Phys. J. C 71, 1547 (2011). [96] M. Aliev, H. Lacker, U. Langenfeld, S. Moch, P. Uwer, and M. Wiedermann, HATHOR—Hadronic Top and Heavy quarks cross section calculator, Comput. Phys. Commun. 182, 1034 (2011). [97] P. Kant, O. M. Kind, T. Kintscher, T. Lohse, T. Martini, S. Mölbitz, P. Rieck, and P. Uwer, HatHor for single topquark production: Updated predictions and uncertainty estimates for single top-quark production in hadronic collisions, Comput. Phys. Commun. 191, 74 (2015). [98] N. Kidonakis, Two-loop soft anomalous dimensions for single top quark associated production with a W−or H−, Phys. Rev. D 82, 054018 (2010). [99] N. Kidonakis, Top quark production, Proceedings, Helmholtz International Summer School on Physics of Heavy Quarks and Hadrons (HQ 2013), (JINR, Dubna, Russia, 2013), p. 139. [100] C. Anastasiou, L. J. Dixon, K. Melnikov, and F. Petriello, High precision QCD at hadron colliders: Electroweak gauge boson rapidity distributions at next-to-next-to leading order, Phys. Rev. D 69, 094008 (2004). G. AAD et al. PHYS. REV. D 104, 112005 (2021) 112005-20 [101] T. Gleisberg and S. Höche, Comix, a new matrix element generator, J. High Energy Phys. 12 (2008) 039. [102] S. Schumann and F. Krauss, A parton shower algorithm based on Catani–Seymour dipole factorisation, J. High Energy Phys. 03 (2008) 038. [103] ATLAS Collaboration, Multi-boson simulation for 13 TeV ATLAS analyses, Report No. ATL-PHYS-PUB-2017-005, 2017, https://cds.cern.ch/record/2261933. [104] J. Alwall, R. Frederix, S. Frixione, V. Hirschi, F. Maltoni, O. Mattelaer, H.-S. Shao, T. Stelzer, P. Torrielli, and M. Zaro, The automated computation of tree-level and nextto-leading order differential cross sections, and their matching to parton shower simulations, J. High Energy Phys. 07 (2014) 079. [105] ATLAS Collaboration, Modelling of the t¯ tH and t¯ tVðV¼ W;ZÞprocesses for ffiffiffi s p¼13 TeV ATLAS analyses, Report No. ATL-PHYS-PUB-2016-005, 2016, https://cds .cern.ch/record/2120826. [106] H. B. Hartanto, B. Jäger, L. Reina, and D. Wackeroth, Higgs boson production in association with top quarks in the P OWHEG B OX ,Phys. Rev. D 91, 094003 (2015). [107] W. Beenakker, C. Borschensky, M. Krämer, A. Kulesza, and E. Laenen, NNLL-fast: Predictions for coloured supersymmetric particle production at the LHC with threshold and Coulomb resummation, J. High Energy Phys. 12 (2016) 133. [108] W. Beenakker, M. Krämer, T. Plehn, M. Spira, and P. Zerwas, Stop production at hadron colliders, Nucl. Phys. B515, 3 (1998). [109] W. Beenakker, S. Brensing, M. Krämer, A. Kulesza, E. Laenen, and I. Niessen, Supersymmetric top and bottom squark production at hadron colliders, J. High Energy Phys. 08 (2010) 098. [110] W. Beenakker, C. Borschensky, R. Heger, M. Krämer, A. Kulesza, and E. Laenen, NNLL resummation for stop pairproduction at the LHC, J. High Energy Phys. 05 (2016) 153. [111] P. Artoisenet, R. Frederix, O. Mattelaer, and R. Rietkerk, Automatic spin-entangled decays of heavy resonances in Monte Carlo simulations, J. High Energy Phys. 03 (2013) 015. [112] L. Lönnblad, Correcting the colour-dipole cascade model with fixed order matrix elements, J. High Energy Phys. 05 (2002) 046. [113] L. Lönnblad and S. Prestel, Matching tree-level matrix elements with interleaved showers, J. High Energy Phys. 03 (2012) 019. [114] T. Mandal, S. Mitra, and S. Seth, Pair production of scalar leptoquarks at the LHC to NLO parton shower accuracy, Phys. Rev. D 93, 035018 (2016). [115] M. Krämer, T. Plehn, M. Spira, and P. Zerwas, Pair production of scalar leptoquarks at the CERN LHC, Phys. Rev. D 71, 057503 (2005). [116] M. Krämer, T. Plehn, M. Spira, and P. Zerwas, Pair Production of Scalar Leptoquarks at the Fermilab Tevatron, Phys. Rev. Lett. 79, 341 (1997). [117] A. Belyaev, C. Leroy, R. Mehdiyev, and A. Pukhov, Leptoquark single and pair production at LHC with CalcHEP/CompHEP in the complete model, J. High Energy Phys. 09 (2005) 005. [118] C. Borschensky, B. Fuks, A. Kulesza, and D. Schwartländer, Scalar leptoquark pair production at hadron colliders, Phys. Rev. D 101, 115017 (2020). [119] M. J. Baker, J. Fuentes-Martín, G. Isidori, and M. König, High-pTsignatures in vector–leptoquark models, Eur. Phys. J. C 79, 334 (2019). [120] J. Blümlein, E. Boos, and A. Kryukov, Leptoquark pair production in hadronic interactions, Z. Phys. C 76, 137 (1997). [121] ATLAS Collaboration, Vertex Reconstruction Performance of the ATLAS Detector at ffiffiffi s p¼13 TeV, Report No. ATL-PHYS-PUB-2015-026, 2015, https://cds.cern.ch/ record/2037717. [122] ATLAS Collaboration, Selection of jets produced in 13 TeV proton–proton collisions with the ATLAS detector, Report No. ATLAS-CONF-2015-029, 2015, https://cds .cern.ch/record/2037702. [123] ATLAS Collaboration, Jet reconstruction and performance using particle flow with the ATLAS detector, Eur. Phys. J. C77, 466 (2017). [124] M. Cacciari, G. P. Salam, and G. Soyez, The anti-ktjet clustering algorithm, J. High Energy Phys. 04 (2008) 063. [125] M. Cacciari, G. P. Salam, and G. Soyez, FastJet user manual, Eur. Phys. J. C 72, 1896 (2012). [126] ATLAS Collaboration, Jet energy scale and resolution measured in proton–proton collisions at ffiffiffi s p¼13 TeV with the ATLAS detector, Eur. Phys. J. C 81, 689 (2021). [127] ATLAS Collaboration, Tagging and suppression of pileup jets with the ATLAS detector, Report No. ATLASCONF2014-018, 2014, https://cds.cern.ch/record/1700870. [128] ATLAS Collaboration, ATLAS b-jet identification performance and efficiency measurement with t¯ tevents in pp collisions at ffiffiffi s p¼13 TeV, Eur. Phys. J. C 79, 970 (2019). [129] ATLAS Collaboration, Optimisation and performance studies of the ATLAS b-tagging algorithms for the 2017-18 LHC run, Report No. ATL-PHYS-PUB-2017013, 2017, https://cds.cern.ch/record/2273281. [130] ATLAS Collaboration, Topological cell clustering in the ATLAS calorimeters and its performance in LHC Run 1, Eur. Phys. J. C 77, 490 (2017). [131] ATLAS Collaboration, Identification and energy calibration of hadronically decaying tau leptons with the ATLAS experiment in pp collisions at ffiffiffi s p¼8TeV, Eur. Phys. J. C75, 303 (2015). [132] ATLAS Collaboration, Measurement of the tau lepton reconstruction and identification performance in the ATLAS experiment using pp collisions at ffiffiffi s p¼13 TeV, Report No. ATLAS-CONF-2017-029, 2017, https://cds .cern.ch/record/2261772. [133] ATLAS Collaboration, Reconstruction of hadronic decay products of tau leptons with the ATLAS experiment, Eur. Phys. J. C 76, 295 (2016). [134] ATLAS Collaboration, Identification of hadronic tau lepton decays using neural networks in the ATLAS experiment, Report No. ATL-PHYS-PUB-2019-033, 2019, https://cds.cern.ch/record/2688062. [135] ATLAS Collaboration, Electron reconstruction and identification in the ATLAS experiment using the 2015 and 2016 LHC proton–proton collision data at ffiffiffi s p¼13 TeV, Eur. Phys. J. C 79, 639 (2019). SEARCH FOR NEW PHENOMENA IN PP COLLISIONS IN …PHYS. REV. D 104, 112005 (2021) 112005-21 [136] ATLAS Collaboration, Electron and photon performance measurements with the ATLAS detector using the 2015– 2017 LHC proton–proton collision data, J. Instrum. 14, P12006 (2019). [137] ATLAS Collaboration, Muon reconstruction and identification efficiency in ATLAS using the full Run 2pp collision data set at ffiffiffi s p¼13 TeV, Eur. Phys. J. C 81, 578 (2021). [138] ATLAS Collaboration, Performance of missing transverse momentum reconstruction with the ATLAS detector using proton–proton collisions at ffiffiffi s p¼13 TeV, Eur. Phys. J. C 78, 903 (2018). [139] ATLAS Collaboration, Emiss Tperformance in the ATLAS detector using 2015–2016 LHC pp collisions, Report No. ATLAS-CONF-2018-023, 2018, https://cds.cern.ch/ record/2625233. [140] G. Cowan, K. Cranmer, E. Gross, and O. Vitells, Asymptotic formulae for likelihood-based tests of new physics, Eur. Phys. J. C 71, 1554 (2011);73, 2501(E) (2013). [141] C. G. Lester and D. J. Summers, Measuring masses of semi-invisibly decaying particles pair produced at hadron colliders, Phys. Lett. B 463, 99 (1999). [142] C. G. Lester and B. Nachman, Bisection-based asymmetric MT2 computation: A higher precision calculator than existing symmetric methods, J. High Energy Phys. 03 (2015) 100. [143] M. Baak, G. J. Besjes, D. Côt´e, A. Koutsman, J. Lorenz, and D. Short, HistFitter software framework for statistical data analysis, Eur. Phys. J. C 75, 153 (2015). [144] J. Butterworth et al., PDF4LHC recommendations for LHC Run II, J. Phys. G 43, 023001 (2016). [145] S. Frixione, E. Laenen, P. Motylinski, C. White, and B. R. Webber, Single-top hadroproduction in association with a W boson, J. High Energy Phys. 07 (2008) 029. [146] S. Catani, F. Krauss, R. Kuhn, and B. R. Webber, QCD matrix elements þparton showers, J. High Energy Phys. 11 (2001) 063. [147] S. Höche, F. Krauss, S. Schumann, and F. Siegert, QCD matrix elements and truncated showers, J. High Energy Phys. 05 (2009) 053. [148] ATLAS Collaboration, Probing the Quantum Interference between Singly and Doubly Resonant Top-Quark Production in pp Collisions at ffiffiffi s p¼13 TeV with the ATLAS Detector, Phys. Rev. Lett. 121, 152002 (2018). [149] ATLAS Collaboration, Studies on top-quark Monte Carlo modelling for Top2016, Report No. ATL-PHYSPUB2016-020, 2016, https://cds.cern.ch/record/2216168. [150] A. L. Read, Presentation of search results: The CLS technique, J. Phys. G 28, 2693 (2002). [151] R. D. Cousins, J. T. Linnemann, and J. Tucker, Evaluation of three methods for calculating statistical significance when incorporating a systematic uncertainty into a test of the background-only hypothesis for a Poisson process, Nucl. Instrum. Methods Phys. Res., Sect. A 595, 480 (2008). [152] The LEP2 SUSY Working Group and ALEPH, DELPHI, L3, OPAL experiments, Combined LEP Selectron/Smuon/ Stau results, 183–208 GeV, http://lepsusy.web.cern.ch/ lepsusy/www/sleptons_summer04/slep_final.html, 2004. [153] ATLAS Collaboration, ATLAS computing acknowledgements, Report No. ATL-SOFT-PUB-2021-003, https://cds .cern.ch/record/2776662. G. Aad,99 B. Abbott,125 D. C. Abbott,100 A. Abed Abud,34 K. Abeling,51 D. K. Abhayasinghe,91 S. H. Abidi,27 O. S. AbouZeid,38 H. Abramowicz,158 H. Abreu,157 Y. Abulaiti,5A. C. Abusleme Hoffman,143a B. S. Acharya,64a,64b,b B. Achkar,51 L. Adam,97 C. Adam Bourdarios,4L. Adamczyk,81a L. Adamek,163 J. Adelman,118 A. Adiguzel,11c,c S. Adorni,52 T. Adye,140 A. A. Affolder,142 Y. Afik,157 C. Agapopoulou,62 M. N. Agaras,12 J. Agarwala,68a,68b A. Aggarwal,116 C. Agheorghiesei,25c J. A. Aguilar-Saavedra,136f,136a,d A. Ahmad,34 F. Ahmadov,77 W. S. Ahmed,101 X. Ai,44 G. Aielli,71a,71b S. Akatsuka,83 M. Akbiyik,97 T. P. A. Åkesson,94 A. V. Akimov,108 K. Al Khoury,37 G. L. Alberghi,21b,21a J. Albert,172 M. J. Alconada Verzini,86 S. Alderweireldt,48 M. Aleksa,34 I. N. Aleksandrov,77 C. Alexa,25b T. Alexopoulos,9 A. Alfonsi,117 F. Alfonsi,21b,21a M. Alhroob,125 B. Ali,138 S. Ali,155 M. Aliev,162 G. Alimonti,66a C. Allaire,34 B. M. M. Allbrooke,153 P. P. Allport,19 A. Aloisio,67a,67b F. Alonso,86 C. Alpigiani,145 E. Alunno Camelia,71a,71b M. Alvarez Estevez,96 M. G. Alviggi,67a,67b Y. Amaral Coutinho,78b A. Ambler,101 L. Ambroz,131 C. Amelung,34 D. Amidei,103 S. P. Amor Dos Santos,136a S. Amoroso,44 C. S. Amrouche,52 C. Anastopoulos,146 N. Andari,141 T. Andeen,10 J. K. Anders,18 S. Y. Andrean,43a,43b A. Andreazza,66a,66b V. Andrei,59a S. Angelidakis,8A. Angerami,37 A. V. Anisenkov,119b,119a A. Annovi,69a C. Antel,52 M. T. Anthony,146 E. Antipov,126 M. Antonelli,49 D. J. A. Antrim,16 F. Anulli,70a M. Aoki,79 J. A. Aparisi Pozo,170 M. A. Aparo,153 L. Aperio Bella,44 N. Aranzabal,34 V. Araujo Ferraz,78a C. Arcangeletti,49 A. T. H. Arce,47 E. Arena,88 J-F. Arguin,107 S. Argyropoulos,50 J.-H. Arling,44 A. J. Armbruster,34 A. Armstrong,167 O. Arnaez,163 H. Arnold,34 Z. P. Arrubarrena Tame,111 G. Artoni,131 H. Asada,114 K. Asai,123 S. Asai,160 N. A. Asbah,57 E. M. Asimakopoulou,168 L. Asquith,153 J. Assahsah,33d K. Assamagan,27 R. Astalos,26a R. J. Atkin,31a M. Atkinson,169 N. B. Atlay,17 H. Atmani,58b P. A. Atmasiddha,103 K. Augsten,138 S. Auricchio,67a,67b V. A. Austrup,178 G. Avolio,34 M. K. Ayoub,13c G. Azuelos,107,e D. Babal,26a H. Bachacou,141 K. Bachas,159 F. Backman,43a,43b A. Badea,57 P. Bagnaia,70a,70b H. Bahrasemani,149 A. J. Bailey,170 V. R. Bailey,169 J. T. Baines,140 C. Bakalis,9O. K. Baker,179 G. AAD et al. PHYS. REV. D 104, 112005 (2021) 112005-22 P. J. Bakker,117 E. Bakos,14 D. Bakshi Gupta,7S. Balaji,154 R. Balasubramanian,117 E. M. Baldin,119b,119a P. Balek,139 E. Ballabene,66a,66b F. Balli,141 W. K. Balunas,131 J. Balz,97 E. Banas,82 M. Bandieramonte,135 A. Bandyopadhyay,17 L. Barak,158 E. L. Barberio,102 D. Barberis,53b,53a M. Barbero,99 G. Barbour,92 K. N. Barends,31a T. Barillari,112 M-S. Barisits,34 J. Barkeloo,128 T. Barklow,150 B. M. Barnett,140 R. M. Barnett,16 A. Baroncelli,58a G. Barone,27 A. J. Barr,131 L. Barranco Navarro,43a,43b F. Barreiro,96 J. Barreiro Guimarães da Costa,13a U. Barron,158 S. Barsov,134 F. Bartels,59a R. Bartoldus,150 G. Bartolini,99 A. E. Barton,87 P. Bartos,26a A. Basalaev,44 A. Basan,97 I. Bashta,72a,72b A. Bassalat,62 M. J. Basso,163 C. R. Basson,98 R. L. Bates,55 S. Batlamous,33e J. R. Batley,30 B. Batool,148 M. Battaglia,142 M. Bauce,70a,70b F. Bauer,141,a P. Bauer,22 H. S. Bawa,29 A. Bayirli,11c J. B. Beacham,47 T. Beau,132 P. H. Beauchemin,166 F. Becherer,50 P. Bechtle,22 H. P. Beck,18,f K. Becker,174 C. Becot,44 A. J. Beddall,11a V. A. Bednyakov,77 C. P. Bee,152 T. A. Beermann,178 M. Begalli,78b M. Begel,27 A. Behera,152 J. K. Behr,44 C. Beirao Da Cruz E Silva,34 J. F. Beirer,51,34 F. Beisiegel,22 M. Belfkir,4G. Bella,158 L. Bellagamba,21b A. Bellerive,32 P. Bellos,19 K. Beloborodov,119b,119a K. Belotskiy,109 N. L. Belyaev,109 D. Benchekroun,33a Y. Benhammou,158 D. P. Benjamin,5M. Benoit,27 J. R. Bensinger,24 S. Bentvelsen,117 L. Beresford,131 M. Beretta,49 D. Berge,17 E. Bergeaas Kuutmann,168 N. Berger,4B. Bergmann,138 L. J. Bergsten,24 J. Beringer,16 S. Berlendis,6G. Bernardi,132 C. Bernius,150 F. U. Bernlochner,22 T. Berry,91 P. Berta,44 A. Berthold,46 I. A. Bertram,87 O. Bessidskaia Bylund,178 S. Bethke,112 A. Betti,40 A. J. Bevan,90 S. Bhatta,152 D. S. Bhattacharya,173 P. Bhattarai,24 V. S. Bhopatkar,5R. Bi,135 R. M. Bianchi,135 O. Biebel,111 R. Bielski,34 N. V. Biesuz,69a,69b M. Biglietti,72a T. R. V. Billoud,138 M. Bindi,51 A. Bingul,11d C. Bini,70a,70b S. Biondi,21b,21a C. J. Birch-sykes,98 G. A. Bird,19,141 M. Birman,176 T. Bisanz,34 J. P. Biswal,2D. Biswas,177,g A. Bitadze,98 C. Bittrich,46 K. Bjørke,130 I. Bloch,44 C. Blocker,24 A. Blue,55 U. Blumenschein,90 J. Blumenthal,97 G. J. Bobbink,117 V. S. Bobrovnikov,119b,119a D. Bogavac,12 A. G. Bogdanchikov,119b,119a C. Bohm,43a V. Boisvert,91 P. Bokan,44 T. Bold,81a M. Bomben,132 M. Bona,90 M. Boonekamp,141 C. D. Booth,91 A. G. Borb´ely,55 H. M. Borecka-Bielska,107 L. S. Borgna,92 G. Borissov,87 D. Bortoletto,131 D. Boscherini,21b M. Bosman,12 J. D. Bossio Sola,101 K. Bouaouda,33a J. Boudreau,135 E. V. Bouhova-Thacker,87 D. Boumediene,36 R. Bouquet,132 A. Boveia,124 J. Boyd,34 D. Boye,27 I. R. Boyko,77 A. J. Bozson,91 J. Bracinik,19 N. Brahimi,58d,58c G. Brandt,178 O. Brandt,30 F. Braren,44 B. Brau,100 J. E. Brau,128 W. D. Breaden Madden,55 K. Brendlinger,44 R. Brener,176 L. Brenner,34 R. Brenner,168 S. Bressler,178 B. Brickwedde,97 D. L. Briglin,19 D. Britton,55 D. Britzger,112 I. Brock,22 R. Brock,104 G. Brooijmans,37 W. K. Brooks,143e E. Brost,27 P. A. Bruckman de Renstrom,82 B. Brüers,44 D. Bruncko,26b A. Bruni,21b G. Bruni,21b M. Bruschi,21b N. Bruscino,70a,70b L. Bryngemark,150 T. Buanes,15 Q. Buat,152 P. Buchholz,148 A. G. Buckley,55 I. A. Budagov,77 M. K. Bugge,130 O. Bulekov,109 B. A. Bullard,57 T. J. Burch,118 S. Burdin,88 C. D. Burgard,44 A. M. Burger,126 B. Burghgrave,7J. T. P. Burr,44 C. D. Burton,10 J. C. Burzynski,100 V. Büscher,97 P. J. Bussey,55 J. M. Butler,23 C. M. Buttar,55 J. M. Butterworth,92 W. Buttinger,140 C. J. Buxo Vazquez,104 A. R. Buzykaev,119b,119a G. Cabras,21b,21a S. Cabrera Urbán,170 D. Caforio,54 H. Cai,135 V. M. M. Cairo,150 O. Cakir,3a N. Calace,34 P. Calafiura,16 G. Calderini,132 P. Calfayan,63 G. Callea,55 L. P. Caloba,78b A. Caltabiano,71a,71b S. Calvente Lopez,96 D. Calvet,36 S. Calvet,36 T. P. Calvet,99 M. Calvetti,69a,69b R. Camacho Toro,132 S. Camarda,34 D. Camarero Munoz,96 P. Camarri,71a,71b M. T. Camerlingo,72a,72b D. Cameron,130 C. Camincher,172 M. Campanelli,92 A. Camplani,38 V. Canale,67a,67b A. Canesse,101 M. Cano Bret,75 J. Cantero,126 Y. Cao,169 M. Capua,39b,39a R. Cardarelli,71a F. Cardillo,170 G. Carducci,39b,39a T. Carli,34 G. Carlino,67a B. T. Carlson,135 E. M. Carlson,172,164a L. Carminati,66a,66b M. Carnesale,70a,70b R. M. D. Carney,150 S. Caron,116 E. Carquin,143e S. Carrá,44 G. Carratta,21b,21a J. W. S. Carter,163 T. M. Carter,48 D. Casadei,31c M. P. Casado,12,h A. F. Casha,163 E. G. Castiglia,179 F. L. Castillo,59a L. Castillo Garcia,12 V. Castillo Gimenez,170 N. F. Castro,136a,136e A. Catinaccio,34 J. R. Catmore,130 A. Cattai,34 V. Cavaliere,27 N. Cavalli,21b,21a V. Cavasinni,69a,69b E. Celebi,11b F. Celli,131 K. Cerny,127 A. S. Cerqueira,78a A. Cerri,153 L. Cerrito,71a,71b F. Cerutti,16 A. Cervelli,21b,21a S. A. Cetin,11b Z. Chadi,33a D. Chakraborty,118 M. Chala,136f J. Chan,177 W. S. Chan,117 W. Y. Chan,88 J. D. Chapman,30 B. Chargeishvili,156b D. G. Charlton,19 T. P. Charman,90 M. Chatterjee,18 C. C. Chau,32 S. Chekanov,5S. V. Chekulaev,164a G. A. Chelkov,77,i A. Chen,103 B. Chen,158 C. Chen,58a C. H. Chen,76 H. Chen,13c H. Chen,27 J. Chen,58a J. Chen,37 J. Chen,24 S. Chen,133 S. J. Chen,13c X. Chen,13b Y. Chen,58a Y-H. Chen,44 C. L. Cheng,177 H. C. Cheng,60a H. J. Cheng,13a A. Cheplakov,77 E. Cheremushkina,44 R. Cherkaoui El Moursli,33e E. Cheu,6K. Cheung,61 L. Chevalier,141 V. Chiarella,49 G. Chiarelli,69a G. Chiodini,65a A. S. Chisholm,19 A. Chitan,25b I. Chiu,160 Y. H. Chiu,172 M. V. Chizhov,77,j K. Choi,10 A. R. Chomont,70a,70b Y. Chou,100 Y. S. Chow,117 L. D. Christopher,31f M. C. Chu,60a X. Chu,13a,13d J. Chudoba,137 J. J. Chwastowski,82 D. Cieri,112 K. M. Ciesla,82 V. Cindro,89 I. A. Cioară,25b A. Ciocio,16 F. Cirotto,67a,67b Z. H. Citron,176,k M. Citterio,66a D. A. Ciubotaru,25b SEARCH FOR NEW PHENOMENA IN PP COLLISIONS IN …PHYS. REV. D 104, 112005 (2021) 112005-23 B. M. Ciungu,163 A. Clark,52 P. J. Clark,48 S. E. Clawson,98 C. Clement,43a,43b L. Clissa,21b,21a Y. Coadou,99 M. Cobal,64a,64c A. Coccaro,53b J. Cochran,76 R. F. Coelho Barrue,136a R. Coelho Lopes De Sa,100 S. Coelli,66a H. Cohen,158 A. E. C. Coimbra,34 B. Cole,37 J. Collot,56 P. Conde Muiño,136a,136h S. H. Connell,31c I. A. Connelly,55 E. I. Conroy,131 F. Conventi,67a,l H. G. Cooke,19 A. M. Cooper-Sarkar,131 F. Cormier,171 L. D. Corpe,34 M. Corradi,70a,70b E. E. Corrigan,94 F. Corriveau,101,m M. J. Costa,170 F. Costanza,4D. Costanzo,146 B. M. Cote,124 G. Cowan,91 J. W. Cowley,30 J. Crane,98 K. Cranmer,122 R. A. Creager,133 S. Cr´ep´e-Renaudin,56 F. Crescioli,132 M. Cristinziani,148 M. Cristoforetti,73a,73b,n V. Croft,166 G. Crosetti,39b,39a A. Cueto,4T. Cuhadar Donszelmann,167 H. Cui,13a,13d A. R. Cukierman,150 W. R. Cunningham,55 S. Czekierda,82 P. Czodrowski,34 M. M. Czurylo,59b M. J. Da Cunha Sargedas De Sousa,58a J. V. Da Fonseca Pinto,78b C. Da Via,98 W. Dabrowski,81a T. Dado,45 S. Dahbi,31f T. Dai,103 C. Dallapiccola,100 M. Dam,38 G. D’amen,27 V. D’Amico,72a,72b J. Damp,97 J. R. Dandoy,133 M. F. Daneri,28 M. Danninger,149 V. Dao,34 G. Darbo,53b S. Darmora,5A. Dattagupta,128 S. D’Auria,66a,66b C. David,164b T. Davidek,139 D. R. Davis,47 B. Davis-Purcell,32 I. Dawson,90 K. De,7R. De Asmundis,67a M. De Beurs,117 S. De Castro,21b,21a N. De Groot,116 P. de Jong,117 H. De la Torre,104 A. De Maria,13c D. De Pedis,70a A. De Salvo,70a U. De Sanctis,71a,71b M. De Santis,71a,71b A. De Santo,153 J. B. De Vivie De Regie,56 D. V. Dedovich,77 J. Degens,117 A. M. Deiana,40 J. Del Peso,96 Y. Delabat Diaz,44 F. Deliot,141 C. M. Delitzsch,6M. Della Pietra,67a,67b D. Della Volpe,52 A. Dell’Acqua,34 L. Dell’Asta,66a,66b M. Delmastro,4 P. A. Delsart,56 S. Demers,179 M. Demichev,77 S. P. Denisov,120 L. D’Eramo,118 D. Derendarz,82 J. E. Derkaoui,33d F. Derue,132 P. Dervan,88 K. Desch,22 K. Dette,163 C. Deutsch,22 P. O. Deviveiros,34 F. A. Di Bello,70a,70b A. Di Ciaccio,71a,71b L. Di Ciaccio,4C. Di Donato,67a,67b A. Di Girolamo,34 G. Di Gregorio,69a,69b A. Di Luca,73a,73b B. Di Micco,72a,72b R. Di Nardo,72a,72b C. Diaconu,99 F. A. Dias,117 T. Dias Do Vale,136a M. A. Diaz,143a F. G. Diaz Capriles,22 J. Dickinson,16 M. Didenko,170 E. B. Diehl,103 J. Dietrich,17 S. Díez Cornell,44 C. Diez Pardos,148 A. Dimitrievska,16 W. Ding,13b J. Dingfelder,22 S. J. Dittmeier,59b F. Dittus,34 F. Djama,99 T. Djobava,156b J. I. Djuvsland,15 M. A. B. Do Vale,144 D. Dodsworth,24 C. Doglioni,94 J. Dolejsi,139 Z. Dolezal,139 M. Donadelli,78c B. Dong,58c J. Donini,36 A. D’onofrio,13c M. D’Onofrio,88 J. Dopke,140 A. Doria,67a M. T. Dova,86 A. T. Doyle,55 E. Drechsler,149 E. Dreyer,149 T. Dreyer,51 A. S. Drobac,166 D. Du,58b T. A. du Pree,117 F. Dubinin,108 M. Dubovsky,26a A. Dubreuil,52 E. Duchovni,176 G. Duckeck,111 O. A. Ducu,34,25b D. Duda,112 A. Dudarev,34 M. D’uffizi,98 L. Duflot,62 M. Dührssen,34 C. Dülsen,178 A. E. Dumitriu,25b M. Dunford,59a S. Dungs,45 A. Duperrin,99 H. Duran Yildiz,3a M. Düren,54 A. Durglishvili,156b B. Dutta,44 D. Duvnjak,1 G. I. Dyckes,133 M. Dyndal,81a S. Dysch,98 B. S. Dziedzic,82 B. Eckerova,26a M. G. Eggleston,47 E. Egidio Purcino De Souza,78b L. F. Ehrke,52 T. Eifert,7G. Eigen,15 K. Einsweiler,16 T. Ekelof,168 Y. El Ghazali,33b H. El Jarrari,33e A. El Moussaouy,33a V. Ellajosyula,168 M. Ellert,168 F. Ellinghaus,178 A. A. Elliot,90 N. Ellis,34 J. Elmsheuser,27 M. Elsing,34 D. Emeliyanov,140 A. Emerman,37 Y. Enari,160 J. Erdmann,45 A. Ereditato,18 P. A. Erland,82 M. Errenst,178 M. Escalier,62 C. Escobar,170 O. Estrada Pastor,170 E. Etzion,158 G. Evans,136a H. Evans,63 M. O. Evans,153 A. Ezhilov,134 F. Fabbri,55 L. Fabbri,21b,21a V. Fabiani,116 G. Facini,174 R. M. Fakhrutdinov,120 S. Falciano,70a P. J. Falke,22 S. Falke,34 J. Faltova,139 Y. Fan,13a Y. Fang,13a Y. Fang,13a G. Fanourakis,42 M. Fanti,66a,66b M. Faraj,58c A. Farbin,7 A. Farilla,72a E. M. Farina,68a,68b T. Farooque,104 S. M. Farrington,48 P. Farthouat,34 F. Fassi,33e D. Fassouliotis,8 M. Faucci Giannelli,71a,71b W. J. Fawcett,30 L. Fayard,62 O. L. Fedin,134,o M. Feickert,169 L. Feligioni,99 A. Fell,146 C. Feng,58b M. Feng,13b M. J. Fenton,167 A. B. Fenyuk,120 S. W. Ferguson,41 J. Ferrando,44 A. Ferrari,168 P. Ferrari,117 R. Ferrari,68a D. Ferrere,52 C. Ferretti,103 F. Fiedler,97 A. Filipčič,89 F. Filthaut,116 M. C. N. Fiolhais,136a,136c,p L. Fiorini,170 F. Fischer,111 W. C. Fisher,104 T. Fitschen,19 I. Fleck,148 P. Fleischmann,103 T. Flick,178 B. M. Flierl,111 L. Flores,133 L. R. Flores Castillo,60a F. M. Follega,73a,73b N. Fomin,15 J. H. Foo,163 G. T. Forcolin,73a,73b B. C. Forland,63 A. Formica,141 F. A. Förster,12 A. C. Forti,98 E. Fortin,99 M. G. Foti,131 D. Fournier,62 H. Fox,87 P. Francavilla,69a,69b S. Francescato,70a,70b M. Franchini,21b,21a S. Franchino,59a D. Francis,34 L. Franco,4L. Franconi,18 M. Franklin,57 G. Frattari,70a,70b A. C. Freegard,90 P. M. Freeman,19 B. Freund,107 W. S. Freund,78b E. M. Freundlich,45 D. Froidevaux,34 J. A. Frost,131 Y. Fu,58a M. Fujimoto,123 E. Fullana Torregrosa,170 T. Fusayasu,113 J. Fuster,170 A. Gabrielli,21b,21a A. Gabrielli,34 P. Gadow,44 G. Gagliardi,53b,53a L. G. Gagnon,16 G. E. Gallardo,131 E. J. Gallas,131 B. J. Gallop,140 R. Gamboa Goni,90 K. K. Gan,124 S. Ganguly,176 J. Gao,58a Y. Gao,48 Y. S. Gao,29,q F. M. Garay Walls,143a C. García,170 J. E. García Navarro,170 J. A. García Pascual,13a M. Garcia-Sciveres,16 R. W. Gardner,35 D. Garg,75 S. Gargiulo,50 C. A. Garner,163 V. Garonne,130 S. J. Gasiorowski,145 P. Gaspar,78b G. Gaudio,68a P. Gauzzi,70a,70b I. L. Gavrilenko,108 A. Gavrilyuk,121 C. Gay,171 G. Gaycken,44 E. N. Gazis,9A. A. Geanta,25b C. M. Gee,142 C. N. P. Gee,140 J. Geisen,94 M. Geisen,97 C. Gemme,53b M. H. Genest,56 S. Gentile,70a,70b S. George,91 T. Geralis,42 L. O. Gerlach,51 P. Gessinger-Befurt,97 G. AAD et al. PHYS. REV. D 104, 112005 (2021) 112005-24 M. Ghasemi Bostanabad,172 M. Ghneimat,148 A. Ghosh,167 A. Ghosh,75 B. Giacobbe,21b S. Giagu,70a,70b N. Giangiacomi,163 P. Giannetti,69a A. Giannini,67a,67b S. M. Gibson,91 M. Gignac,142 D. T. Gil,81b B. J. Gilbert,37 D. Gillberg,32 G. Gilles,178 N. E. K. Gillwald,44 D. M. Gingrich,2,e M. P. Giordani,64a,64c P. F. Giraud,141 G. Giugliarelli,64a,64c D. Giugni,66a F. Giuli,71a,71b I. Gkialas,8,r E. L. Gkougkousis,12 P. Gkountoumis,9L. K. Gladilin,110 C. Glasman,96 G. R. Gledhill,128 M. Glisic,128 I. Gnesi,39b,s M. Goblirsch-Kolb,24 D. Godin,107 S. Goldfarb,102 T. Golling,52 D. Golubkov,120 J. P. Gombas,104 A. Gomes,136a,136b R. Goncalves Gama,51 R. Gonçalo,136a,136c G. Gonella,128 L. Gonella,19 A. Gongadze,77 F. Gonnella,19 J. L. Gonski,37 S. González de la Hoz,170 S. Gonzalez Fernandez,12 R. Gonzalez Lopez,88 C. Gonzalez Renteria,16 R. Gonzalez Suarez,168 S. Gonzalez-Sevilla,52 G. R. Gonzalvo Rodriguez,170 R. Y. González Andana,143a L. Goossens,34 N. A. Gorasia,19 P. A. Gorbounov,121 H. A. Gordon,27 B. Gorini,34 E. Gorini,65a,65b A. Gorišek,89 A. T. Goshaw,47 M. I. Gostkin,77 C. A. Gottardo,116 M. Gouighri,33b V. Goumarre,44 A. G. Goussiou,145 N. Govender,31c C. Goy,4 I. Grabowska-Bold,81a K. Graham,32 E. Gramstad,130 S. Grancagnolo,17 M. Grandi,153 V. Gratchev,134 P. M. Gravila,25f F. G. Gravili,65a,65b H. M. Gray,16 C. Grefe,22 I. M. Gregor,44 P. Grenier,150 K. Grevtsov,44 C. Grieco,12 N. A. Grieser,125 A. A. Grillo,142 K. Grimm,29,t S. Grinstein,12,u J.-F. Grivaz,62 S. Groh,97 E. Gross,176 J. Grosse-Knetter,51 Z. J. Grout,92 C. Grud,103 A. Grummer,115 J. C. Grundy,131 L. Guan,103 W. Guan,177 C. Gubbels,171 J. Guenther,34 J. G. R. Guerrero Rojas,170 F. Guescini,112 D. Guest,17 R. Gugel,97 A. Guida,44 T. Guillemin,4S. Guindon,34 J. Guo,58c L. Guo,62 Y. Guo,103 R. Gupta,44 S. Gurbuz,22 G. Gustavino,125 M. Guth,50 P. Gutierrez,125 L. F. Gutierrez Zagazeta,133 C. Gutschow,92 C. Guyot,141 C. Gwenlan,131 C. B. Gwilliam,88 E. S. Haaland,130 A. Haas,122 M. Habedank,17 C. Haber,16 H. K. Hadavand,7A. Hadef,97 M. Haleem,173 J. Haley,126 J. J. Hall,146 G. Halladjian,104 G. D. Hallewell,99 L. Halser,18 K. Hamano,172 H. Hamdaoui,33e M. Hamer,22 G. N. Hamity,48 K. Han,58a L. Han,13c L. Han,58a S. Han,16 Y. F. Han,163 K. Hanagaki,79,v M. Hance,142 M. D. Hank,35 R. Hankache,98 E. Hansen,94 J. B. Hansen,38 J. D. Hansen,38 M. C. Hansen,22 P. H. Hansen,38 K. Hara,165 T. Harenberg,178 S. Harkusha,105 Y. T. Harris,131 P. F. Harrison,174 N. M. Hartman,150 N. M. Hartmann,111 Y. Hasegawa,147 A. Hasib,48 S. Hassani,141 S. Haug,18 R. Hauser,104 M. Havranek,138 C. M. Hawkes,19 R. J. Hawkings,34 S. Hayashida,114 D. Hayden,104 C. Hayes,103 R. L. Hayes,171 C. P. Hays,131 J. M. Hays,90 H. S. Hayward,88 S. J. Haywood,140 F. He,58a Y. He,161 Y. He,132 M. P. Heath,48 V. Hedberg,94 A. L. Heggelund,130 N. D. Hehir,90 C. Heidegger,50 K. K. Heidegger,50 W. D. Heidorn,76 J. Heilman,32 S. Heim,44 T. Heim,16 B. Heinemann,44,w J. G. Heinlein,133 J. J. Heinrich,128 L. Heinrich,34 J. Hejbal,137 L. Helary,44 A. Held,122 S. Hellesund,130 C. M. Helling,142 S. Hellman,43a,43b C. Helsens,34 R. C. W. Henderson,87 L. Henkelmann,30 A. M. Henriques Correia,34 H. Herde,150 Y. Hernández Jim´enez,152 H. Herr,97 M. G. Herrmann,111 T. Herrmann,46 G. Herten,50 R. Hertenberger,111 L. Hervas,34 N. P. Hessey,164a H. Hibi,80 S. Higashino,79 E. Higón-Rodriguez,170 K. K. Hill,27 K. H. Hiller,44 S. J. Hillier,19 M. Hils,46 I. Hinchliffe,16 F. Hinterkeuser,22 M. Hirose,129 S. Hirose,165 D. Hirschbuehl,178 B. Hiti,89 O. Hladik,137 J. Hobbs,152 R. Hobincu,25e N. Hod,176 M. C. Hodgkinson,146 B. H. Hodkinson,30 A. Hoecker,34 J. Hofer,44 D. Hohn,50 T. Holm,22 T. R. Holmes,35 M. Holzbock,112 L. B. A. H. Hommels,30 B. P. Honan,98 T. M. Hong,135 J. C. Honig,50 A. Hönle,112 B. H. Hooberman,169 W. H. Hopkins,5Y. Horii,114 P. Horn,46 L. A. Horyn,35 S. Hou,155 J. Howarth,55 J. Hoya,86 M. Hrabovsky,127 A. Hrynevich,106 T. Hryn’ova,4P. J. Hsu,61 S.-C. Hsu,145 Q. Hu,37 S. Hu,58c Y. F. Hu,13a,13d,x D. P. Huang,92 X. Huang,13c Y. Huang,58a Y. Huang,13a Z. Hubacek,138 F. Hubaut,99 M. Huebner,22 F. Huegging,22 T. B. Huffman,131 M. Huhtinen,34 R. Hulsken,56 N. Huseynov,77,y J. Huston,104 J. Huth,57 R. Hyneman,150 S. Hyrych,26a G. Iacobucci,52 G. Iakovidis,27 I. Ibragimov,148 L. Iconomidou-Fayard,62 P. Iengo,34 R. Ignazzi,38 R. Iguchi,160 T. Iizawa,52 Y. Ikegami,79 A. Ilg,18 N. Ilic,163 H. Imam,33a G. Introzzi,68a,68b M. Iodice,72a V. Ippolito,70a,70b M. Ishino,160 W. Islam,126 C. Issever,17,44 S. Istin,11c,z J. M. Iturbe Ponce,60a R. Iuppa,73a,73b A. Ivina,176 J. M. Izen,41 V. Izzo,67a P. Jacka,137 P. Jackson,1 R. M. Jacobs,44 B. P. Jaeger,149 C. S. Jagfeld,111 G. Jäkel,178 K. B. Jakobi,97 K. Jakobs,50 T. Jakoubek,176 J. Jamieson,55 K. W. Janas,81a G. Jarlskog,94 A. E. Jaspan,88 N. Javadov,77,y T. Javůrek,34 M. Javurkova,100 F. Jeanneau,141 L. Jeanty,128 J. Jejelava,156a P. Jenni,50,aa S. J´ez´equel,4J. Jia,152 Z. Jia,13c Y. Jiang,58a S. Jiggins,50 J. Jimenez Pena,112 S. Jin,13c A. Jinaru,25b O. Jinnouchi,161 H. Jivan,31f P. Johansson,146 K. A. Johns,6C. A. Johnson,63 E. Jones,174 R. W. L. Jones,87 T. J. Jones,88 J. Jovicevic,34 X. Ju,16 J. J. Junggeburth,34 A. Juste Rozas,12,u A. Kaczmarska,82 M. Kado,70a,70b H. Kagan,124 M. Kagan,150 A. Kahn,37 C. Kahra,97 T. Kaji,175 E. Kajomovitz,157 C. W. Kalderon,27 A. Kaluza,97 A. Kamenshchikov,120 M. Kaneda,160 N. J. Kang,142 S. Kang,76 Y. Kano,114 J. Kanzaki,79 D. Kar,31f K. Karava,131 M. J. Kareem,164b I. Karkanias,159 S. N. Karpov,77 Z. M. Karpova,77 V. Kartvelishvili,87 A. N. Karyukhin,120 E. Kasimi,159 C. Kato,58d J. Katzy,44 K. Kawade,147 K. Kawagoe,85 T. Kawaguchi,114 T. Kawamoto,141 G. Kawamura,51 E. F. Kay,172 F. I. Kaya,166 S. Kazakos,12 V. F. Kazanin,119b,119a Y. Ke,152 J. M. Keaveney,31a R. Keeler,172 J. S. Keller,32 D. Kelsey,153 J. J. Kempster,19 J. Kendrick,19 SEARCH FOR NEW PHENOMENA IN PP COLLISIONS IN …PHYS. REV. D 104, 112005 (2021) 112005-25 53aDipartimento di Fisica, Universit`a di Genova, Genova, Italy 53bINFN Sezione di Genova, Italy 54II. Physikalisches Institut, Justus-Liebig-Universität Giessen, Giessen, Germany 55SUPA—School of Physics and Astronomy, University of Glasgow, Glasgow, United Kingdom 56LPSC, Universit´e Grenoble Alpes, CNRS/IN2P3, Grenoble INP, Grenoble, France 57Laboratory for Particle Physics and Cosmology, Harvard University, Cambridge Massachusetts, USA 58aDepartment of Modern Physics and State Key Laboratory of Particle Detection and Electronics, University of Science and Technology of China, Hefei, China 58bInstitute of Frontier and Interdisciplinary Science and Key Laboratory of Particle Physics and Particle Irradiation (MOE), Shandong University, Qingdao, China 58cSchool of Physics and Astronomy, Shanghai Jiao Tong University, Key Laboratory for Particle Astrophysics and Cosmology (MOE), SKLPPC, Shanghai, China 58dTsung-Dao Lee Institute, Shanghai, China 59aKirchhoff-Institut für Physik, Ruprecht-Karls-Universität Heidelberg, Heidelberg, Germany 59bPhysikalisches Institut, Ruprecht-Karls-Universität Heidelberg, Heidelberg, Germany 60aDepartment of Physics, Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China 60bDepartment of Physics, University of Hong Kong, Hong Kong, China 60cDepartment of Physics and Institute for Advanced Study, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China 61Department of Physics, National Tsing Hua University, Hsinchu, Taiwan 62IJCLab, Universit´e Paris-Saclay, CNRS/IN2P3, 91405, Orsay, France 63Department of Physics, Indiana University, Bloomington Indiana, USA 64aINFN Gruppo Collegato di Udine, Sezione di Trieste, Udine, Italy 64bICTP, Trieste, Italy 64cDipartimento Politecnico di Ingegneria e Architettura, Universit`a di Udine, Udine, Italy 65aINFN Sezione di Lecce, Italy 65bDipartimento di Matematica e Fisica, Universit`a del Salento, Lecce, Italy 66aINFN Sezione di Milano, Italy 66bDipartimento di Fisica, Universit`a di Milano, Milano, Italy 67aINFN Sezione di Napoli, Italy 67bDipartimento di Fisica, Universit`a di Napoli, Napoli, Italy 68aINFN Sezione di Pavia, Italy 68bDipartimento di Fisica, Universit`a di Pavia, Pavia, Italy 69aINFN Sezione di Pisa, Italy 69bDipartimento di Fisica E. Fermi, Universit`a di Pisa, Pisa, Italy 70aINFN Sezione di Roma, Italy 70bDipartimento di Fisica, Sapienza Universit`a di Roma, Roma, Italy 71aINFN Sezione di Roma Tor Vergata, Italy 71bDipartimento di Fisica, Universit`a di Roma Tor Vergata, Roma, Italy 72aINFN Sezione di Roma Tre, Italy 72bDipartimento di Matematica e Fisica, Universit`a Roma Tre, Roma, Italy 73aINFN-TIFPA, Italy 73bUniversit`a degli Studi di Trento, Trento, Italy 74Institut für Astround Teilchenphysik, Leopold-Franzens-Universität, Innsbruck, Austria 75University of Iowa, Iowa City Iowa, USA 76Department of Physics and Astronomy, Iowa State University, Ames Iowa, USA 77Joint Institute for Nuclear Research, Dubna, Russia 78aDepartamento de Engenharia El´etrica, Universidade Federal de Juiz de Fora (UFJF), Juiz de Fora, Brazil 78bUniversidade Federal do Rio De Janeiro COPPE/EE/IF, Rio de Janeiro, Brazil 78cInstituto de Física, Universidade de São Paulo, São Paulo, Brazil 79KEK, High Energy Accelerator Research Organization, Tsukuba, Japan 80Graduate School of Science, Kobe University, Kobe, Japan 81aAGH University of Science and Technology, Faculty of Physics and Applied Computer Science, Krakow, Poland 81bMarian Smoluchowski Institute of Physics, Jagiellonian University, Krakow, Poland 82Institute of Nuclear Physics Polish Academy of Sciences, Krakow, Poland 83Faculty of Science, Kyoto University, Kyoto, Japan 84Kyoto University of Education, Kyoto, Japan G. AAD et al. PHYS. REV. D 104, 112005 (2021) 112005-32 85Research Center for Advanced Particle Physics and Department of Physics, Kyushu University, Fukuoka, Japan 86Instituto de Física La Plata, Universidad Nacional de La Plata and CONICET, La Plata, Argentina 87Physics Department, Lancaster University, Lancaster, United Kingdom 88Oliver Lodge Laboratory, University of Liverpool, Liverpool, United Kingdom 89Department of Experimental Particle Physics, Jožef Stefan Institute and Department of Physics, University of Ljubljana, Ljubljana, Slovenia 90School of Physics and Astronomy, Queen Mary University of London, London, United Kingdom 91Department of Physics, Royal Holloway University of London, Egham, United Kingdom 92Department of Physics and Astronomy, University College London, London, United Kingdom 93Louisiana Tech University, Ruston Louisiana, USA 94Fysiska institutionen, Lunds universitet, Lund, Sweden 95Centre de Calcul de l’Institut National de Physique Nucl´eaire et de Physique des Particules (IN2P3), Villeurbanne, France 96Departamento de Física Teorica C-15 and CIAFF, Universidad Autónoma de Madrid, Madrid, Spain 97Institut für Physik, Universität Mainz, Mainz, Germany 98School of Physics and Astronomy, University of Manchester, Manchester, United Kingdom 99CPPM, Aix-Marseille Universit´e, CNRS/IN2P3, Marseille, France 100Department of Physics, University of Massachusetts, Amherst Massachusetts, USA 101Department of Physics, McGill University, Montreal QC, Canada 102School of Physics, University of Melbourne, Victoria, Australia 103Department of Physics, University of Michigan, Ann Arbor Michigan, USA 104Department of Physics and Astronomy, Michigan State University, East Lansing Michigan, USA 105B.I. Stepanov Institute of Physics, National Academy of Sciences of Belarus, Minsk, Belarus 106Research Institute for Nuclear Problems of Byelorussian State University, Minsk, Belarus 107Group of Particle Physics, University of Montreal, Montreal QC, Canada 108P.N. Lebedev Physical Institute of the Russian Academy of Sciences, Moscow, Russia 109National Research Nuclear University MEPhI, Moscow, Russia 110D.V. Skobeltsyn Institute of Nuclear Physics, M.V. Lomonosov Moscow State University, Moscow, Russia 111Fakultät für Physik, Ludwig-Maximilians-Universität München, München, Germany 112Max-Planck-Institut für Physik (Werner-Heisenberg-Institut), München, Germany 113Nagasaki Institute of Applied Science, Nagasaki, Japan 114Graduate School of Science and Kobayashi-Maskawa Institute, Nagoya University, Nagoya, Japan 115Department of Physics and Astronomy, University of New Mexico, Albuquerque New Mexico, USA 116Institute for Mathematics, Astrophysics and Particle Physics, Radboud University/Nikhef, Nijmegen, Netherlands 117Nikhef National Institute for Subatomic Physics and University of Amsterdam, Amsterdam, Netherlands 118Department of Physics, Northern Illinois University, DeKalb Illinois, USA 119aBudker Institute of Nuclear Physics and NSU, SB RAS, Novosibirsk, Russia 119bNovosibirsk State University Novosibirsk, Russia 120Institute for High Energy Physics of the National Research Centre Kurchatov Institute, Protvino, Russia 121Institute for Theoretical and Experimental Physics named by A.I. Alikhanov of National Research Centre “Kurchatov Institute”, Moscow, Russia 122Department of Physics, New York University, New York New York, USA 123Ochanomizu University, Otsuka, Bunkyo-ku, Tokyo, Japan 124The Ohio State University, Columbus Ohio, USA 125Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, Norman Oklahoma, USA 126Department of Physics, Oklahoma State University, Stillwater Oklahoma, USA 127Palacký University, Joint Laboratory of Optics, Olomouc, Czech Republic 128Institute for Fundamental Science, University of Oregon, Eugene, Oregon, USA 129Graduate School of Science, Osaka University, Osaka, Japan 130Department of Physics, University of Oslo, Oslo, Norway 131Department of Physics, Oxford University, Oxford, United Kingdom 132LPNHE, Sorbonne Universit´e, Universit´e de Paris, CNRS/IN2P3, Paris, France 133Department of Physics, University of Pennsylvania, Philadelphia Pennsylvania, USA 134Konstantinov Nuclear Physics Institute of National Research Centre “Kurchatov Institute”, PNPI, St. Petersburg, Russia 135Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh Pennsylvania, USA SEARCH FOR NEW PHENOMENA IN PP COLLISIONS IN …PHYS. REV. D 104, 112005 (2021) 112005-33 136aLaboratório de Instrumentação e Física Experimental de Partículas—LIP, Lisboa, Portugal 136bDepartamento de Física, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal 136cDepartamento de Física, Universidade de Coimbra, Coimbra, Portugal 136dCentro de Física Nuclear da Universidade de Lisboa, Lisboa, Portugal 136eDepartamento de Física, Universidade do Minho, Braga, Portugal 136fDepartamento de Física Teórica y del Cosmos, Universidad de Granada, Granada (Spain), Spain 136gDep Física and CEFITEC of Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Caparica, Portugal 136hInstituto Superior T´ecnico, Universidade de Lisboa, Lisboa, Portugal 137Institute of Physics of the Czech Academy of Sciences, Prague, Czech Republic 138Czech Technical University in Prague, Prague, Czech Republic 139Charles University, Faculty of Mathematics and Physics, Prague, Czech Republic 140Particle Physics Department, Rutherford Appleton Laboratory, Didcot, United Kingdom 141IRFU, CEA, Universit´e Paris-Saclay, Gif-sur-Yvette, France 142Santa Cruz Institute for Particle Physics, University of California Santa Cruz, Santa Cruz California, USA 143aDepartamento de Física, Pontificia Universidad Católica de Chile, Santiago, Chile 143bUniversidad de la Serena, La Serena, Chile 143cUniversidad Andres Bello, Department of Physics, Santiago, Chile 143dInstituto de Alta Investigación, Universidad de Tarapacá, Arica, Chile 143eDepartamento de Física, Universidad T´ecnica Federico Santa María, Valparaíso, Chile 144Universidade Federal de São João del Rei (UFSJ), São João del Rei, Brazil 145Department of Physics, University of Washington, Seattle Washington, USA 146Department of Physics and Astronomy, University of Sheffield, Sheffield, United Kingdom 147Department of Physics, Shinshu University, Nagano, Japan 148Department Physik, Universität Siegen, Siegen, Germany 149Department of Physics, Simon Fraser University, Burnaby BC, Canada 150SLAC National Accelerator Laboratory, Stanford California, USA 151Department of Physics, Royal Institute of Technology, Stockholm, Sweden 152Departments of Physics and Astronomy, Stony Brook University, Stony Brook New York, USA 153Department of Physics and Astronomy, University of Sussex, Brighton, United Kingdom 154School of Physics, University of Sydney, Sydney, Australia 155Institute of Physics, Academia Sinica, Taipei, Taiwan 156aE. Andronikashvili Institute of Physics, Iv. Javakhishvili Tbilisi State University, Tbilisi, Georgia 156bHigh Energy Physics Institute, Tbilisi State University, Tbilisi, Georgia 157Department of Physics, Technion, Israel Institute of Technology, Haifa, Israel 158Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Tel Aviv, Israel 159Department of Physics, Aristotle University of Thessaloniki, Thessaloniki, Greece 160International Center for Elementary Particle Physics and Department of Physics, University of Tokyo, Tokyo, Japan 161Department of Physics, Tokyo Institute of Technology, Tokyo, Japan 162Tomsk State University, Tomsk, Russia 163Department of Physics, University of Toronto, Toronto ON, Canada 164aTRIUMF, Vancouver BC, Canada 164bDepartment of Physics and Astronomy, York University, Toronto ON, Canada 165Division of Physics and Tomonaga Center for the History of the Universe, Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Japan 166Department of Physics and Astronomy, Tufts University, Medford Massachusetts, USA 167Department of Physics and Astronomy, University of California Irvine, Irvine California, USA 168Department of Physics and Astronomy, University of Uppsala, Uppsala, Sweden 169Department of Physics, University of Illinois, Urbana Illinois, USA 170Instituto de Física Corpuscular (IFIC), Centro Mixto Universidad de Valencia—CSIC, Valencia, Spain 171Department of Physics, University of British Columbia, Vancouver BC, Canada 172Department of Physics and Astronomy, University of Victoria, Victoria BC, Canada 173Fakultät für Physik und Astronomie, Julius-Maximilians-Universität Würzburg, Würzburg, Germany 174Department of Physics, University of Warwick, Coventry, United Kingdom 175Waseda University, Tokyo, Japan 176Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, Israel 177Department of Physics, University of Wisconsin, Madison Wisconsin, USA G. AAD et al. PHYS. REV. D 104, 112005 (2021) 112005-34 178Fakultät für Mathematik und Naturwissenschaften, Fachgruppe Physik, Bergische Universität Wuppertal, Wuppertal, Germany 179Department of Physics, Yale University, New Haven Connecticut, USA aDeceased. bAlso at Department of Physics, King’s College London, London, United Kingdom. cAlso at Istanbul University, Dept. of Physics, Istanbul, Turkey. dAlso at Instituto de Fisica Teorica, IFT-UAM/CSIC, Madrid, Spain. eAlso at TRIUMF, Vancouver BC, Canada. fAlso at Department of Physics, University of Fribourg, Fribourg, Switzerland. gAlso at Department of Physics and Astronomy, University of Louisville, Louisville, Kentucky, USA. hAlso at Departament de Fisica de la Universitat Autonoma de Barcelona, Barcelona, Spain. iAlso at Moscow Institute of Physics and Technology State University, Dolgoprudny, Russia. jAlso at Faculty of Physics, Sofia University, ’St. Kliment Ohridski’, Sofia, Bulgaria. kAlso at Department of Physics, Ben Gurion University of the Negev, Beer Sheva, Israel. lAlso at Universita di Napoli Parthenope, Napoli, Italy. mAlso at Institute of Particle Physics (IPP), Canada. nAlso at Bruno Kessler Foundation, Trento, Italy. oAlso at Department of Physics, St. Petersburg State Polytechnical University, St. Petersburg, Russia. pAlso at Borough of Manhattan Community College, City University of New York, New York New York, USA. qAlso at Department of Physics, California State University, Fresno, USA. rAlso at Department of Financial and Management Engineering, University of the Aegean, Chios, Greece. sAlso at Centro Studi e Ricerche Enrico Fermi, Italy. tAlso at Department of Physics, California State University, East Bay, Hayward, California, USA. uAlso at Institucio Catalana de Recerca i Estudis Avancats, ICREA, Barcelona, Spain. vAlso at Graduate School of Science, Osaka University, Osaka, Japan. wAlso at Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany. xAlso at University of Chinese Academy of Sciences (UCAS), Beijing, China. yAlso at Institute of Physics, Azerbaijan Academy of Sciences, Baku, Azerbaijan. zAlso at Yeditepe University, Physics Department, Istanbul, Turkey. aaAlso at CERN, Geneva, Switzerland. bbAlso at Joint Institute for Nuclear Research, Dubna, Russia. ccAlso at Hellenic Open University, Patras, Greece. ddAlso at Center for High Energy Physics, Peking University, China. eeAlso at The City College of New York, New York New York, USA. ffAlso at Department of Physics, California State University, Sacramento, USA. ggAlso at D´epartement de Physique Nucl´eaire et Corpusculaire, Universit´e de Gen`eve, Gen`eve, Switzerland. hhAlso at Faculty of Physics, M.V. Lomonosov Moscow State University, Moscow, Russia. iiAlso at Institut für Experimentalphysik, Universität Hamburg, Hamburg, Germany. jjAlso at CPPM, Aix-Marseille Universit´e, CNRS/IN2P3, Marseille, France. kkAlso at National Research Nuclear University MEPhI, Moscow, Russia. llAlso at Institute for Particle and Nuclear Physics, Wigner Research Centre for Physics, Budapest, Hungary. mmAlso at Giresun University, Faculty of Engineering, Giresun, Turkey. nnAlso at Department of Physics and Astronomy, Michigan State University, East Lansing Michigan, USA. SEARCH FOR NEW PHENOMENA IN PP COLLISIONS IN …PHYS. REV. D 104, 112005 (2021) 112005-35