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Test of lepton flavour universality in $W$-boson decays into electrons and $\tau$-leptons using $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector

T0 review · 1 major / 5 minor · reviewed 2026-08-11 · deepseek-v4-flash

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Pith's one-line read New measurement finds tau and electron couplings to the W boson equal within about 2.4% total uncertainty.

desk verdict First ATLAS R_tau/e from top-quark decays, consistent with the SM at 2.4% precision; a solid, careful measurement whose only real soft spot is the simulation-only transfer of fake-electron corrections from same-sign to opposite-sign events. read the letter →

arxiv 2412.11989 v2 pith:XLPRUIDT submitted 2024-12-16 hep-ex

ATLAS Collaboration This is my paper · ORCID
classification hep-ex PACS 13.38.Be14.60.Fg
keywords leptonflavouruniversalityWbosonbranchingfractiontauimpactparametertopquarkdecaytemplatefitproton-protoncollisions
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The reading

The paper establishes a measurement of the ratio of W-boson branching fractions to tau leptons and to electrons, R_tau/e = 0.975 ± 0.012 (stat) ± 0.020 (syst). This is consistent with the Standard Model assumption that the W boson couples to all charged leptons with the same strength, a property called lepton flavour universality. The result is the first measurement of this ratio using W bosons produced in top-quark decays, and it improves the precision of the worldwide average for R_tau/e. If correct, it confirms that any difference between tau and electron couplings to the W boson is smaller than about 2.4%, tightening the experimental constraints on new-physics models that violate lepton flavour universality.

What carries the argument

The central object is the ratio R_tau/e of W-boson branching fractions. The analysis uses a tag-and-probe selection: one lepton tags a top-quark decay in ttbar events and the other electron probes the W decay. The two sources, direct W -> e nu and W -> tau nu -> e nu nu nu, are separated by a two-dimensional template fit to the electron transverse momentum and the absolute value of the transverse impact parameter, the distance of closest approach of the electron track to the beamline. Electrons from tau decays have lower momenta because neutrinos carry energy, and larger impact parameters because the tau lives briefly before decaying; the prompt-electron templates are calibrated with a data sample of Z -> e+ e- events, while tau-decay templates come from simulation corrected for the measured impact-parameter resolution. The ratio is extracted as the parameter of interest in a profile likelihood with more than 300 nuisance parameters.

What would settle it

A measurement of R_tau/e using an independent opposite-sign control region enriched in fake electrons, or a direct data-driven determination of the fake-electron transfer factor, that shifts the central value beyond the quoted systematic uncertainty would challenge the result; likewise, a future more precise measurement that excludes R_tau/e = 1 at the few-percent level would contradict the Standard Model expectation of lepton flavour universality.

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Extended reading notes

Core claim

The central claim, stated as equation (5) of the paper, is R_tau/e = 0.975 ± 0.012 ± 0.020, with a total uncertainty of 0.024. The measurement uses top-quark pair events where one W boson decays to a tau (which then decays to an electron and neutrinos) and the other W decays directly to an electron; the two cases are separated by the electron's transverse momentum and its impact parameter with respect to the beamline. The value agrees with the Standard Model prediction R_tau/e = 1 and with the previous proton-proton collider measurement, while differing from the combined electron-positron collider result by more than two standard deviations. The paper argues that the measurement will reduce the uncertainty in the world average for R_tau/e.

Load-bearing premise

The analysis assumes that fake-electron correction factors measured in a same-sign control sample can be transported to the opposite-sign signal region, with the transfer factor taken from Monte Carlo simulation rather than an independent data control region.

Editorial extensions

If this is right

  • If correct, the tau and electron couplings to the W boson are equal within about 2.4% total uncertainty.
  • The measurement contributes to the world average for R_tau/e, improving its precision.
  • It agrees with the previous proton-proton collider measurement and disagrees with the electron-positron collider combination by more than two standard deviations, so the tension in the world data remains.
  • Combined with the already precise R_mu/e measurement, it sharpens the overall test of lepton flavour universality in W-boson decays.
  • The use of the electron impact parameter distribution as the discriminating variable is demonstrated as a practical technique for this channel.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • A natural next step is to combine R_tau/e with R_mu/e to test the full triangle of lepton-flavour ratios; if all three agree with unity at sub-percent level, new physics in W-lepton couplings would be constrained below current sensitivity.
  • The same impact-parameter template method could be applied to measure R_tau/mu directly using muons from tau decays, avoiding electron identification uncertainties entirely.
  • If the discrepancy with the electron-positron collider result persists as more data accumulate, it may point to a genuine effect or to a systematic in one of the collider environments; the added collision data will adjudicate.
  • The quoted uncertainty includes the rate of tau -> e nu nu; a more precise measurement of this branching fraction would directly improve R_tau/e in this channel.
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Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, and a circularity audit.

Referee Report

1 major / 5 minor

Summary. The ATLAS Collaboration presents the first measurement of R_tau/e = B(W -> tau nu)/B(W -> e nu) using top-quark decays, with 140 fb^-1 of pp collision data at sqrt(s)=13 TeV. Events are selected with one tag lepton and one probe electron, and the two W-decay categories are separated using the electron transverse impact parameter and pT distributions in a binned profile likelihood fit. The measured value is R_tau/e = 0.975 +/- 0.012 (stat) +/- 0.020 (syst), consistent with the Standard Model expectation of lepton flavour universality. The analysis relies on data-driven d0 templates from Z->ee events, same-sign control samples to derive fake-electron correction factors, and a detailed systematic evaluation dominated by ttbar/Wt modelling, d0 calibration, and background estimation.

Significance. If correct, this measurement provides a new precision test of lepton flavour universality in on-shell W-boson decays, with an uncertainty comparable to the CMS result and the LEP combination, and it reduces the world-average uncertainty on R_tau/e. The statistical framework is clearly specified, with a binned likelihood and nuisance parameters, and the d0 calibration using a large Z->ee sample is a notable strength. The paper also ships a transparent systematic breakdown, including generator comparisons for the dominant modelling uncertainties. The principal weakness is the reliance on simulation for the same-sign to opposite-sign fake-electron extrapolation, which is not closed with a dedicated data control region.

major comments (1)
  1. [Section 6 and Table 4] The fake-electron correction factors (C_HAD, C_PH, C_PR) are fitted in a same-sign control sample and then transported to the opposite-sign signal region using a transfer factor evaluated entirely from simulation, as stated in Section 6: 'The extrapolation of the correction factor from the same-sign to opposite-sign sample is evaluated from simulated events.' The assigned 'Background estimation' systematic of 0.005 in Table 4 is derived from the same-sign fit, a Pythia/Herwig comparison, and a photon-conversion fraction variation, but it does not directly test the charge-sign-dependent transfer. In the 7-10 GeV pT bin, fakes are ~11% of the selected events (Table 1: 317 of 2770, compared to 1092 tau-signal events); a 20% bias in the OS fake rate would shift R_tau/e by roughly 0.03-0.05, which is comparable to or larger than the quoted total uncertainty of 0.024. I request either a data-driven closure test in an opposite-sign fake-enriched control region or an enlarged systematic that explicitly covers the SS-to-OS extrapolation, along with a discussion of how the current generator comparison constrains this source.
minor comments (5)
  1. [Section 8, Table 3] The pT-binned results show R_tau/e = 1.13 +/- 0.13 in the 7-10 GeV bin, which is the bin with the largest fake fraction and where the SS-to-OS extrapolation is most uncertain; a sentence interpreting this upward trend and its consistency with the combined result would be helpful.
  2. [Table 4] The label 'Total systematical uncertainty' should read 'Total systematic uncertainty'.
  3. [Eq. (3)] The likelihood uses Gaussian constraints for all nuisance parameters, including normalization-type uncertainties; for large pulls, log-normal constraints would be more appropriate, and a brief justification of the Gaussian choice would improve the statistical presentation.
  4. [Figure 8] The caption should state explicitly that the PDG average value shown does not include this new ATLAS measurement, otherwise a reader may assume the average already contains the result.
  5. [Section 6] The statement 'It was verified that the separate treatment of electrons and muons from these sources had no statistically significant impact on the result' would benefit from a quantitative value (e.g., the shift in R_tau/e) so that the reader can assess the sensitivity.

Circularity Check

0 steps flagged · score 0.0 of 10

No circularity found: R_tau/e is floated in a template fit with Z-data-calibrated d0 shapes; backgrounds are data-constrained; the one self-citation is methodological and non-load-bearing.

full rationale

The analysis chain is self-contained with respect to R_tau/e. Section 7 defines the likelihood with R_tau/e as the floated parameter of interest, while the simulation is normalized with the SM value R_tau/e = 1; the fit extracts the ratio from the shapes of the pT and |d0| distributions. Prompt-electron d0 templates are derived from a Z -> e+e- data control sample (Section 5), not from the signal hypothesis; tau-decay templates come from simulation corrected for resolution using Z data, with the tau lifetime as an external input. Backgrounds are constrained by data control regions (the Z-mass fit and the same-sign fake-electron fit), and the same-sign-to-opposite-sign extrapolation of fake corrections is a simulation-based transfer evaluated as a systematic uncertainty, not an input that fixes R_tau/e. The only self-citation to Ref. [10] is for the d0-resolution correction method and is methodological rather than load-bearing; it does not supply the value of R_tau/e or forbid alternatives. No equation reduces to its own input by construction.

Assumptions & free parameters 10 free parameters · 6 assumptions · 0 invented entities

The central claim rests on a chain of calibration and background corrections, all anchored to data control samples or to independently measured external quantities. The main numerical inputs are the measured tau lifetime, the PDG value of B(tau to e nu nu), and the correction factors fitted in control regions. No new physical entity is introduced, and none of the external inputs assumes the target value of R_tau/e.

free parameters (10)
  • R_tau/e (parameter of interest) = 0.975 +/- 0.024 (total)
    This is the measured output, floated in the profile likelihood; it is not an input assumption.
  • k_sig = 1.03 +/- 0.06
    Global normalization of ttbar and Wt signal in the final likelihood, floated in the fit to data.
  • k_(mu/e) = 0.986 +/- 0.010
    Residual ratio of tag muon to tag electron selection efficiencies, floated in the fit to data.
  • C_Z^i (Drell-Yan scale factors) = average 1.117 +/- 0.013, per pT bin
    Scale factors for Z+jets and Z to tau tau backgrounds obtained from the m_ee control sample fit.
  • C_HAD = 1.41 +/- 0.03
    Correction factor for fake electrons from hadron decays, measured in the same-sign control sample.
  • C_PH = 0.84 +/- 0.05
    Correction factor for fake electrons from photon conversions, measured in the same-sign control sample.
  • C_PR = 1.45 +/- 0.08
    Correction factor for prompt same-sign leptons, measured in the same-sign control sample.
  • d0 resolution scale = about 15 um at pT = 20 GeV, per year and kinematic bin
    Gaussian width of the prompt-electron d0 distribution fitted in Z data and applied to tau-decay and fake-electron templates in simulation.
  • Low-pT electron efficiency correction = derived from Z data/MC ratio, value not tabulated
    Additional correction for electrons below 15 GeV where the standard tag-and-probe efficiency measurement is unreliable.
  • Systematic nuisance parameters (about 300) = constrained near their nominal values in the fit
    Nuisance parameters for PDFs, jet energy scale and resolution, b-tagging, lepton efficiencies, pile-up, and MC statistical uncertainties; their combined impact is summarized in Table 4.
assumptions (6)
  • domain assumption The top quark decays almost exclusively to a W boson and a bottom quark, so ttbar and Wt events provide a clean source of W bosons.
    Section 4 selects ttbar-like events with two b-tagged jets, one tag lepton, and one probe electron; the signal definition relies on this Standard Model decay pattern.
  • domain assumption Monte Carlo generators and the ATLAS detector simulation accurately model the kinematics, acceptance, and backgrounds after the stated reweighting and calibrations.
    All signal and background templates are built from simulated events; generator uncertainties are evaluated by comparisons but cannot be fully excluded.
  • domain assumption The d0 distribution of prompt electrons from W decays is identical to that from Z to ee decays after calibration.
    Section 5 constructs prompt-electron d0 templates from Z to ee data; Equation (4) assigns a systematic uncertainty for residual MC-derived differences.
  • domain assumption The tau-lepton lifetime and the branching fraction B(tau to e nu nu) are known from external measurements and are used as inputs.
    The tau d0 template is the convolution of the resolution with the lifetime distribution, and the measured B(tau to e nu nu) enters the signal yield; both are taken from prior measurements with uncertainties.
  • domain assumption Fake-electron yields in the opposite-sign signal region can be extrapolated from the same-sign control region using simulation-derived ratios.
    Section 6 fits C_HAD, C_PH, and C_PR to same-sign events and applies them to the nominal sample; the same-sign to opposite-sign extrapolation is not directly measured.
  • standard math The binned profile likelihood with Gaussian nuisance constraints yields unbiased estimates and uncertainties for R_tau/e.
    Equation (3) defines the likelihood; standard likelihood asymptotics are assumed, and no explicit coverage or pull validation is shown in this paper.

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Cite this review

Pith. "Pith review of Test of lepton flavour universality in $W$-boson decays into electrons and $\tau$-leptons using $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector." pith.science (2026). https://pith.science/paper/XLPRUIDT

@misc{pith2026241211989,
  author       = {Pith},
  title        = {Pith review of: Test of lepton flavour universality in $W$-boson decays into electrons and $\tau$-leptons using $pp$ collisions at $\sqrts=13$ TeV with the ATLAS detector},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/XLPRUIDT}},
  note         = {Machine review of arXiv:2412.11989}
}
abstract

A measurement of the ratio of the branching fractions, $R_{\tau/e} = B(W \to \tau \nu)/ B(W \to e \nu)$, is performed using a sample of $W$ bosons originating from top-quark decays to final states containing $\tau$-leptons or electrons. This measurement uses $pp$ collisions at $\sqrt{s}=13$ TeV, collected by the ATLAS experiment at the Large Hadron Collider during Run 2, corresponding to an integrated luminosity of 140 fb$^{-1}$. The $W \to \tau \nu_\tau$ (with $\tau \to e \nu_e \nu_\tau$) and $W \to e \nu_e$ decays are distinguished using the differences in the impact parameter distributions and transverse momentum spectra of the electrons. The measured ratio of branching fractions $R_{\tau/e} = 0.975 \pm 0.012 \textrm{(stat.)} \pm 0.020 \textrm{(syst.)}$, is consistent with the Standard Model assumption of lepton flavour universality in $W$-boson decays.

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Reference graph

Works this paper leans on

98 extracted references · 80 linked inside Pith

  1. [1]

    S. L. Glashow,Partial-symmetries of weak interactions, Nucl. Phys.22(1961) 579

    1961

  2. [2]

    Weinberg, A Model of Leptons, Phys

    S. Weinberg, A Model of Leptons, Phys. Rev. Lett.19 (1967) 1264

    1967

  3. [3]

    Salam, Weak and Electromagnetic Interactions, Conf

    A. Salam, Weak and Electromagnetic Interactions, Conf. Proc. C680519 (1968) 367

    1968

  4. [4]

    Pich, Precision Tau Physics, Prog

    A. Pich, Precision Tau Physics, Prog. Part. Nucl. Phys.75(2014) 41, arXiv: 1310.7922 [hep-ph]

    arXiv 2014

  5. [5]

    Navas et al.,Review of particle physics, Phys

    Particle Data Group, S. Navas et al.,Review of particle physics, Phys. Rev. D110 (2024) 030001

    2024

  6. [6]

    Crivellin, M

    A. Crivellin, M. Kirk, T. Kitahara and F. Mescia,Global fit of modified quark couplings to EW gauge bosons and vector-like quarks in light of the Cabibbo angle anomaly, JHEP03(2023) 234, arXiv: 2212.06862 [hep-ph]

    arXiv 2023

  7. [7]

    Allwicher, G

    L. Allwicher, G. Isidori, J. M. Lizana, N. Selimović and B. A. Stefanek, Third-family quark-lepton Unification and electroweak precision tests, JHEP05 (2023) 179, arXiv: 2302.11584 [hep-ph]

    arXiv 2023

  8. [8]

    Abada, J

    A. Abada, J. Kriewald, E. Pinsard, S. Rosauro-Alcaraz and A. M. Teixeira, Heavy neutral lepton corrections to SM boson decays: lepton flavour universality violation in low-scale seesaw realisations, Eur. Phys. J. C84(2024) 149, arXiv:2307.02558 [hep-ph]

    arXiv 2024

Show all 98 references
  1. [9]

    Rept.532 (2013) 119, arXiv:1302.3415 [hep-ex]

    The ALEPH Collaboration, The DELPHI Collaboration, The L3 Collaboration, The OPAL Collaboration, The LEP Electroweak Working Group, Electroweak Measurements in Electron-Positron Collisions at W-Boson-Pair Energies at LEP, Phys. Rept.532 (2013) 119, arXiv:1302.3415 [hep-ex]

    2013 arXiv

  2. [10]

    ATLAS Collaboration, Test of the universality of𝜏 and𝜇 lepton couplings in𝑊-boson decays with the ATLAS detector, Nature Phys.17(2021) 813, arXiv:2007.14040 [hep-ex]

    2021 arXiv

  3. [11]

    CMS Collaboration, Precision measurement of the W boson decay branching fractions in proton-proton collisions at√𝑠 = 13 TeV, Phys. Rev. D105 (2022) 072008, arXiv: 2201.07861 [hep-ex]

    2022 arXiv

  4. [12]

    ATLAS Collaboration,Precise test of lepton flavour universality in𝑊-boson decays into muons and electrons in𝑝𝑝 collisions at√𝑠= 13TeV with the ATLAS detector, Eur. Phys. J. C84(2024) 993, arXiv: 2403.02133 [hep-ex]

    2024 arXiv

  5. [13]

    ATLAS Collaboration, The ATLAS Experiment at the CERN Large Hadron Collider, JINST3 (2008) S08003

    2008

  6. [14]

    ATLAS Collaboration, ATLAS Insertable B-Layer: Technical Design Report, ATLAS-TDR-19; CERN-LHCC-2010-013, 2010, url: https://cds.cern.ch/record/1291633, Addendum: ATLAS-TDR-19-ADD-1; CERN-LHCC-2012-009, 2012,url: https://cds.cern.ch/record/1451888

    2010

  7. [15]

    Abbott et al.,Production and integration of the ATLAS Insertable B-Layer, JINST13(2018) T05008, arXiv:1803.00844 [physics.ins-det]

    B. Abbott et al.,Production and integration of the ATLAS Insertable B-Layer, JINST13(2018) T05008, arXiv:1803.00844 [physics.ins-det]

    2018 arXiv

  8. [16]

    Avoni et al.,The new LUCID-2 detector for luminosity measurement and monitoring in ATLAS, JINST13 (2018) P07017

    G. Avoni et al.,The new LUCID-2 detector for luminosity measurement and monitoring in ATLAS, JINST13 (2018) P07017

    2018

  9. [17]

    ATLAS Collaboration, Performance of the ATLAS trigger system in 2015, Eur. Phys. J. C77(2017) 317, arXiv:1611.09661 [hep-ex]. 27

    2017 arXiv

  10. [18]

    ATLAS Collaboration, Software and computing for Run 3 of the ATLAS experiment at the LHC, 2024, arXiv:2404.06335 [hep-ex]

    2024 arXiv

  11. [19]

    ATLAS Collaboration,ATLAS data quality operations and performance for 2015–2018 data-taking, JINST15 (2020) P04003, arXiv:1911.04632 [physics.ins-det]

    2020 arXiv

  12. [20]

    ATLAS Collaboration, Luminosity determination in𝑝𝑝 collisions at√𝑠= 13TeV using the ATLAS detector at the LHC, Eur. Phys. J. C83(2023) 982, arXiv:2212.09379 [hep-ex]

    2023 arXiv

  13. [21]

    Agostinelli et al.,GEANT4–a simulation toolkit, Nucl

    S. Agostinelli et al.,GEANT4–a simulation toolkit, Nucl. Instrum. Meth. A506 (2003) 250

    2003

  14. [22]

    ATLAS Collaboration, The ATLAS Simulation Infrastructure, Eur. Phys. J. C70(2010) 823, arXiv: 1005.4568 [physics.ins-det]

    2010 arXiv

  15. [23]

    Sjöstrand, S

    T. Sjöstrand, S. Mrenna and P. Skands,A brief introduction to PYTHIA 8.1, Comput. Phys. Commun.178 (2008) 852, arXiv:0710.3820 [hep-ph]

    2008 arXiv

  16. [24]

    NNPDF Collaboration, R. D. Ball et al.,Parton distributions with LHC data, Nucl. Phys. B867 (2013) 244, arXiv:1207.1303 [hep-ph]

    2013 arXiv

  17. [25]

    ATLAS Collaboration, The Pythia 8 A3 tune description of ATLAS minimum bias and inelastic measurements incorporating the Donnachie–Landshoff diffractive model, ATL-PHYS-PUB-2016-017, 2016,url: https://cds.cern.ch/record/2206965

    2016

  18. [26]

    ATLAS Collaboration, ATLAS Pythia 8 tunes to7TeV data, ATL-PHYS-PUB-2014-021, 2014, url: https://cds.cern.ch/record/1966419

    2014

  19. [27]

    Bähr et al.,Herwig++ physics and manual, Eur

    M. Bähr et al.,Herwig++ physics and manual, Eur. Phys. J. C58(2008) 639, arXiv: 0803.0883 [hep-ph]

    2008 arXiv

  20. [28]

    Bellm et al.,Herwig 7.1 Release Note, 2017, arXiv:1705.06919 [hep-ph]

    J. Bellm et al.,Herwig 7.1 Release Note, 2017, arXiv:1705.06919 [hep-ph]

    2017 arXiv

  21. [29]

    D. J. Lange,The EvtGen particle decay simulation package, Nucl. Instrum. Meth. A462 (2001) 152

    2001

  22. [30]

    Frixione, G

    S. Frixione, G. Ridolfi and P. Nason, A positive-weight next-to-leading-order Monte Carlo for heavy flavour hadroproduction, JHEP 09(2007) 126, arXiv:0707.3088 [hep-ph]

    2007 arXiv

  23. [31]

    Nason, A new method for combining NLO QCD with shower Monte Carlo algorithms, JHEP 11(2004) 040, arXiv:hep-ph/0409146

    P. Nason, A new method for combining NLO QCD with shower Monte Carlo algorithms, JHEP 11(2004) 040, arXiv:hep-ph/0409146

    2004 arXiv

  24. [32]

    Frixione, P

    S. Frixione, P. Nason and C. Oleari, Matching NLO QCD computations with parton shower simulations: the POWHEG method, JHEP 11(2007) 070, arXiv:0709.2092 [hep-ph]

    2007 arXiv

  25. [33]

    Alioli, P

    S. Alioli, P. Nason, C. Oleari and E. Re,A general framework for implementing NLO calculations in shower Monte Carlo programs: the POWHEG BOX, JHEP06 (2010) 043, arXiv: 1002.2581 [hep-ph]

    2010 arXiv

  26. [34]

    NNPDF Collaboration, R. D. Ball et al.,Parton distributions for the LHC run II, JHEP04(2015) 040, arXiv:1410.8849 [hep-ph]

    2015 arXiv

  27. [35]

    ATLAS Collaboration, Studies on top-quark Monte Carlo modelling for Top2016, ATL-PHYS-PUB-2016-020, 2016,url: https://cds.cern.ch/record/2216168

    2016

  28. [36]

    Sjöstrand et al.,An introduction to PYTHIA 8.2, Comput

    T. Sjöstrand et al.,An introduction to PYTHIA 8.2, Comput. Phys. Commun.191 (2015) 159, arXiv: 1410.3012 [hep-ph]. 28

    2015 arXiv

  29. [37]

    Czakon et al.,Top-pair production at the LHC through NNLO QCD and NLO EW, JHEP10(2017) 186, arXiv:1705.04105 [hep-ph]

    M. Czakon et al.,Top-pair production at the LHC through NNLO QCD and NLO EW, JHEP10(2017) 186, arXiv:1705.04105 [hep-ph]

    2017 arXiv

  30. [38]

    Beneke, P

    M. Beneke, P. Falgari, S. Klein and C. Schwinn, Hadronic top-quark pair production with NNLL threshold resummation, Nucl. Phys. B855 (2012) 695, arXiv:1109.1536 [hep-ph]

    2012 arXiv

  31. [39]

    Cacciari, M

    M. Cacciari, M. Czakon, M. Mangano, A. Mitov and P. Nason,Top-pair production at hadron colliders with next-to-next-to-leading logarithmic soft-gluon resummation, Phys. Lett. B710 (2012) 612, arXiv:1111.5869 [hep-ph]

    2012 arXiv

  32. [40]

    Bärnreuther, M

    P. Bärnreuther, M. Czakon and A. Mitov,Percent-Level-Precision Physics at the Tevatron: Next-to-Next-to-Leading Order QCD Corrections to𝑞 ¯𝑞→𝑡¯𝑡+𝑋, Phys. Rev. Lett.109 (2012) 132001, arXiv:1204.5201 [hep-ph]

    2012 arXiv

  33. [41]

    Czakon and A

    M. Czakon and A. Mitov, NNLO corrections to top-pair production at hadron colliders: the all-fermionic scattering channels, JHEP12(2012) 054, arXiv:1207.0236 [hep-ph]

    2012 arXiv

  34. [42]

    Czakon and A

    M. Czakon and A. Mitov, NNLO corrections to top pair production at hadron colliders: the quark-gluon reaction, JHEP01(2013) 080, arXiv:1210.6832 [hep-ph]

    2013 arXiv

  35. [43]

    Czakon, P

    M. Czakon, P. Fiedler and A. Mitov, Total Top-Quark Pair-Production Cross Section at Hadron Colliders ThroughO(𝛼4 𝑆), Phys. Rev. Lett.110 (2013) 252004, arXiv:1303.6254 [hep-ph]

    2013 arXiv

  36. [44]

    Czakon and A

    M. Czakon and A. Mitov, Top++: A program for the calculation of the top-pair cross-section at hadron colliders, Comput. Phys. Commun.185 (2014) 2930, arXiv:1112.5675 [hep-ph]

    2014 arXiv

  37. [45]

    Butterworth et al.,PDF4LHC recommendations for LHC Run II, J

    J. Butterworth et al.,PDF4LHC recommendations for LHC Run II, J. Phys. G43(2016) 023001, arXiv: 1510.03865 [hep-ph]

    2016 arXiv

  38. [46]

    A. D. Martin, W. J. Stirling, R. S. Thorne and G. Watt,Parton distributions for the LHC, Eur. Phys. J. C63(2009) 189, arXiv:0901.0002 [hep-ph]

    2009 arXiv

  39. [47]

    A. D. Martin, W. J. Stirling, R. S. Thorne and G. Watt, Uncertainties on𝛼𝑆 in global PDF analyses and implications for predicted hadronic cross sections, Eur. Phys. J. C64(2009) 653, arXiv:0905.3531 [hep-ph]

    2009 arXiv

  40. [48]

    Lai et al.,New parton distributions for collider physics, Phys

    H.-L. Lai et al.,New parton distributions for collider physics, Phys. Rev. D82(2010) 074024, arXiv: 1007.2241 [hep-ph]

    2010 arXiv

  41. [49]

    Gao et al.,CT10 next-to-next-to-leading order global analysis of QCD, Phys

    J. Gao et al.,CT10 next-to-next-to-leading order global analysis of QCD, Phys. Rev. D89 (2014) 033009, arXiv:1302.6246 [hep-ph]

    2014 arXiv

  42. [50]

    Frixione, E

    S. Frixione, E. Laenen, P. Motylinski, C. White and B. R. Webber, Single-top hadroproduction in association with a𝑊 boson, JHEP07(2008) 029, arXiv: 0805.3067 [hep-ph]

    2008 arXiv

  43. [51]

    Kidonakis, Two-loop soft anomalous dimensions for single top quark associated production with a𝑊− or𝐻−, Phys

    N. Kidonakis, Two-loop soft anomalous dimensions for single top quark associated production with a𝑊− or𝐻−, Phys. Rev. D82 (2010) 054018, arXiv:1005.4451 [hep-ph]

    2010 arXiv

  44. [52]

    N. Kidonakis, ‘Top Quark Production’,Proceedings, Helmholtz International Summer School on Physics of Heavy Quarks and Hadrons (HQ 2013)(JINR, Dubna, Russia, 15th–28th July 2013) 139, arXiv: 1311.0283 [hep-ph]. 29

    2013 arXiv

  45. [53]

    J. Alwall et al.,The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations, JHEP07(2014) 079, arXiv: 1405.0301 [hep-ph]

    2014 arXiv

  46. [54]

    Frixione, E

    S. Frixione, E. Laenen, P. Motylinski and B. R. Webber,Angular correlations of lepton pairs from vector boson and top quark decays in Monte Carlo simulations, JHEP04 (2007) 081, arXiv: hep-ph/0702198

    2007 arXiv

  47. [55]

    Artoisenet, R

    P. Artoisenet, R. Frederix, O. Mattelaer and R. Rietkerk, Automatic spin-entangled decays of heavy resonances in Monte Carlo simulations, JHEP03(2013) 015, arXiv:1212.3460 [hep-ph]

    2013 arXiv

  48. [56]

    de Florian et al., Handbook of LHC Higgs Cross Sections: 4

    D. de Florian et al., Handbook of LHC Higgs Cross Sections: 4. Deciphering the Nature of the Higgs Sector, 2017, arXiv: 1610.07922 [hep-ph]

    2017 arXiv

  49. [57]

    H. B. Hartanto, B. Jäger, L. Reina and D. Wackeroth, Higgs boson production in association with top quarks in the POWHEG BOX, Phys. Rev. D91 (2015) 094003, arXiv:1501.04498 [hep-ph]

    2015 arXiv

  50. [58]

    Bothmann et al.,Event generation with Sherpa 2.2, SciPost Phys.7(2019) 034, arXiv: 1905.09127 [hep-ph]

    E. Bothmann et al.,Event generation with Sherpa 2.2, SciPost Phys.7(2019) 034, arXiv: 1905.09127 [hep-ph]

    2019 arXiv

  51. [59]

    Gleisberg and S

    T. Gleisberg and S. Höche,Comix, a new matrix element generator, JHEP12(2008) 039, arXiv: 0808.3674 [hep-ph]

    2008 arXiv

  52. [60]

    Buccioni et al.,OpenLoops 2, Eur

    F. Buccioni et al.,OpenLoops 2, Eur. Phys. J. C79(2019) 866, arXiv:1907.13071 [hep-ph]

    2019 arXiv

  53. [61]

    Cascioli, P

    F. Cascioli, P. Maierhöfer and S. Pozzorini,Scattering Amplitudes with Open Loops, Phys. Rev. Lett.108 (2012) 111601, arXiv:1111.5206 [hep-ph]

    2012 arXiv

  54. [62]

    Denner, S

    A. Denner, S. Dittmaier and L. Hofer, Collier: A fortran-based complex one-loop library in extended regularizations, Comput. Phys. Commun.212 (2017) 220, arXiv:1604.06792 [hep-ph]

    2017 arXiv

  55. [63]

    Schumann and F

    S. Schumann and F. Krauss, A parton shower algorithm based on Catani–Seymour dipole factorisation, JHEP03(2008) 038, arXiv: 0709.1027 [hep-ph]

    2008 arXiv

  56. [64]

    Winter, F

    J.-C. Winter, F. Krauss and G. Soff,A modified cluster-hadronisation model, Eur. Phys. J. C36(2004) 381, arXiv:hep-ph/0311085

    2004 arXiv

  57. [65]

    Höche, F

    S. Höche, F. Krauss, M. Schönherr and F. Siegert, A critical appraisal of NLO+PS matching methods, JHEP09 (2012) 049, arXiv: 1111.1220 [hep-ph]

    2012 arXiv

  58. [66]

    Catani, F

    S. Catani, F. Krauss, B. R. Webber and R. Kuhn,QCD Matrix Elements + Parton Showers, JHEP 11(2001) 063, arXiv:hep-ph/0109231

    2001 arXiv

  59. [67]

    Höche, F

    S. Höche, F. Krauss, S. Schumann and F. Siegert,QCD matrix elements and truncated showers, JHEP 05(2009) 053, arXiv:0903.1219 [hep-ph]

    2009 arXiv

  60. [68]

    Höche, F

    S. Höche, F. Krauss, M. Schönherr and F. Siegert, QCD matrix elements + parton showers. The NLO case, JHEP04(2013) 027, arXiv: 1207.5030 [hep-ph]. 30

    2013 arXiv

  61. [69]

    Frederix, E

    R. Frederix, E. Re and P. Torrielli, Single-top𝑡-channel hadroproduction in the four-flavour scheme with POWHEG and aMC@NLO, JHEP09(2012) 130, arXiv:1207.5391 [hep-ph]

    2012 arXiv

  62. [70]

    L. A. Harland-Lang, A. D. Martin, P. Motylinski and R. S. Thorne, Parton distributions in the LHC era: MMHT 2014 PDFs, Eur. Phys. J. C75(2015) 204, arXiv: 1412.3989 [hep-ph]

    2015 arXiv

  63. [71]

    Höche, S

    S. Höche, S. Mrenna, S. Payne, C. T. Preuss and P. Skands, A Study of QCD Radiation in VBF Higgs Production with Vincia and Pythia, SciPost Phys.12 (2022) 010, arXiv:2106.10987 [hep-ph]

    2022 arXiv

  64. [72]

    ATLAS Collaboration, Studies on the improvement of the matching uncertainty definition in top-quark processes simulated withPowheg+Pythia8, ATL-PHYS-PUB-2023-029, 2013, url: https://cds.cern.ch/record/2872787

    2023

  65. [73]

    Lönnblad, Correcting the Colour-Dipole Cascade Model with Fixed Order Matrix Elements, JHEP 05(2002) 046, arXiv:hep-ph/0112284

    L. Lönnblad, Correcting the Colour-Dipole Cascade Model with Fixed Order Matrix Elements, JHEP 05(2002) 046, arXiv:hep-ph/0112284

    2002 arXiv

  66. [74]

    Lönnblad and S

    L. Lönnblad and S. Prestel,Matching tree-level matrix elements with interleaved showers, JHEP 03(2012) 019, arXiv:1109.4829 [hep-ph]

    2012 arXiv

  67. [75]

    Anastasiou, L

    C. Anastasiou, L. 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. D69 (2004) 094008, arXiv:hep-ph/0312266

    2004 arXiv

  68. [76]

    ATLAS Collaboration, Electron and photon performance measurements with the ATLAS detector using the 2015–2017 LHC proton-proton collision data, JINST14(2019) P12006, arXiv: 1908.00005 [hep-ex]

    2019 arXiv

  69. [77]

    ATLAS Collaboration,Electron and photon efficiencies in LHC Run 2 with the ATLAS experiment, JHEP05(2024) 162, arXiv:2308.13362 [hep-ex]

    2024 arXiv

  70. [78]

    ATLAS Collaboration, Muon reconstruction and identification efficiency in ATLAS using the full Run 2𝑝𝑝 collision data set at√𝑠= 13 TeV, Eur. Phys. J. C81(2021) 578, arXiv: 2012.00578 [hep-ex]

    2021 arXiv

  71. [79]

    ATLAS Collaboration, The ATLAS inner detector trigger performance in𝑝𝑝 collisions at13TeV during LHC Run 2, Eur. Phys. J. C82(2022) 206, arXiv:2107.02485 [hep-ex]

    2022 arXiv

  72. [80]

    ATLAS Collaboration, Performance of electron and photon triggers in ATLAS during LHC Run 2, Eur. Phys. J. C80(2020) 47, arXiv:1909.00761 [hep-ex]

    2020 arXiv

  73. [81]

    ATLAS Collaboration, Performance of the ATLAS muon triggers in Run 2, JINST15(2020) P09015, arXiv:2004.13447 [physics.ins-det]

    2020 arXiv

  74. [82]

    Cacciari, G

    M. Cacciari, G. P. Salam and G. Soyez,The anti-𝑘𝑡 jet clustering algorithm, JHEP04(2008) 063, arXiv: 0802.1189 [hep-ph]

    2008 arXiv

  75. [83]

    Cacciari, G

    M. Cacciari, G. P. Salam and G. Soyez,FastJet User Manual, Eur. Phys. J. C72(2012) 1896, arXiv: 1111.6097 [hep-ph]

    2012 arXiv

  76. [84]

    ATLAS Collaboration, Jet reconstruction and performance using particle flow with the ATLAS Detector, Eur. Phys. J. C77(2017) 466, arXiv:1703.10485 [hep-ex]. 31

    2017 arXiv

  77. [85]

    ATLAS Collaboration, Jet energy scale and resolution measured in proton–proton collisions at√𝑠= 13TeV with the ATLAS detector, Eur. Phys. J. C81 (2021) 689, arXiv: 2007.02645 [hep-ex]

    2021 arXiv

  78. [86]

    ATLAS Collaboration, Performance of pile-up mitigation techniques for jets in𝑝𝑝 collisions at√𝑠= 8TeV using the ATLAS detector, Eur. Phys. J. C76 (2016) 581, arXiv: 1510.03823 [hep-ex]

    2016 arXiv

  79. [87]

    ATLAS Collaboration, ATLAS flavour-tagging algorithms for the LHC Run 2 pp collision dataset, Eur. Phys. J. C83(2023) 681, arXiv:2211.16345 [physics.data-an]

    2023 arXiv

  80. [88]

    Belous et al.,Measurement of the𝜏-lepton lifetime at Belle, Phys

    Belle Collaboration, K. Belous et al.,Measurement of the𝜏-lepton lifetime at Belle, Phys. Rev. Lett.112 (2014) 031801, arXiv:1310.8503 [hep-ex]

    2014 arXiv

  81. [89]

    Barlow, Extended maximum likelihood, Nucl

    R. Barlow, Extended maximum likelihood, Nucl. Instrum. Meth. A297 (1990) 496

    1990

  82. [90]

    Voigt, Über das Gesetz der Intensitätsverteilung innerhalb der Linien eines Gasspektrums, Sitzungsberichte, vol

    W. Voigt, Über das Gesetz der Intensitätsverteilung innerhalb der Linien eines Gasspektrums, Sitzungsberichte, vol. 25, Königlich Bayerische Akademie der Wissenschaften, Munich, Germany, 1912 603

    1912

  83. [91]

    R. D. Cousins,Generalization of Chisquare Goodness-of-Fit Test for Binned Data Using Saturated Models, with Application to Histograms, url: http://www.physics.ucla.edu/~cousins/stats/cousins_saturated.pdf

  84. [92]

    ATLAS Collaboration, Electron and photon energy calibration with the ATLAS detector using LHC Run 2 data, JINST19 (2024) P02009, arXiv:2309.05471 [hep-ex]

    2024 arXiv

  85. [93]

    ATLAS Collaboration,Studies of the muon momentum calibration and performance of the ATLAS detector with𝑝𝑝 collisions at√𝑠= 13TeV, Eur. Phys. J. C83 (2023) 686, arXiv: 2212.07338 [hep-ex]

    2023 arXiv

  86. [94]

    ATLAS Collaboration,ATLAS b-jet identification performance and efficiency measurement with𝑡¯𝑡 events in pp collisions at√𝑠= 13 TeV, Eur. Phys. J. C79(2019) 970, arXiv: 1907.05120 [hep-ex]

    2019 arXiv

  87. [95]

    ATLAS Collaboration,Measurement of the c-jet mistagging efficiency in𝑡¯𝑡 events using pp collision data at√𝑠= 13TeV collected with the ATLAS detector, Eur. Phys. J. C82(2022) 95, arXiv: 2109.10627 [hep-ex]

    2022 arXiv

  88. [96]

    ATLAS Collaboration, Calibration of the light-flavour jet mistagging efficiency of the b-tagging algorithms with Z+jets events using 139 fb−1 of ATLAS proton–proton collision data at√𝑠= 13TeV, Eur. Phys. J. C83(2023) 728, arXiv:2301.06319 [hep-ex]

    2023 arXiv

  89. [97]

    Barlow and C

    R. Barlow and C. Beeston,Fitting using finite Monte Carlo samples, Comput. Phys. Commun.77(1993) 219

    1993

  90. [98]

    Demokritos

    ATLAS Collaboration, ATLAS Computing Acknowledgements, ATL-SOFT-PUB-2023-001, 2023, url: https://cds.cern.ch/record/2869272. 32 The ATLAS Collaboration G. Aad 105, E. Aakvaag 17, B. Abbott 124, S. Abdelhameed 120a, K. Abeling 57, N.J. Abicht 51, S.H. Abidi 30, M. Aboelela 46, ...

    2023

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