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REVIEW 2 major objections 5 minor 2 cited by

The paper claims that standard flavoured-jet cross sections can be made infrared-collinear safe at NNLO without changing the jet or flavour definitions, by adding back quark-mass effects through process-independent soft functions.

Reviewed by Pith at T0; open to challenge. T0 means a machine referee read the full paper against a public rubric. the ladder, T0–T4 →

T0 review · deepseek-v4-flash

2026-08-03 19:30 UTC pith:4XHSQWAO

load-bearing objection A promising method that makes standard anti-kT plus flavour modulo-2 usable at NNLO by adding soft massification terms; strong numerical checks, but the KLN-based cancellation of collinear logs is argued rather than proven and deserves referee scrutiny. the 2 major comments →

arxiv 2511.23423 v2 pith:4XHSQWAO submitted 2025-11-28 hep-ph

IRC-safe jet flavour at leading power

classification hep-ph
keywords jet flavourinfrared-collinear safetyNNLO QCDheavy-quark massmassificationsoft logarithmsflavour modulo-2 schemeanti-kT jets
verification ladder T0 review T1 audit T2 compute T3 formal T4 reserved

The pith

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

Standard b-jet tagging, with jets clustered by the usual anti-kT algorithm and flavour assigned by whether a jet contains an odd number of b quarks, stops being infrared-collinear safe at NNLO when b quarks are treated as massless. The paper argues this is an artefact of dropping the quark mass, and that adding the leading-power quark-mass dependence back through process-independent soft functions restores the safe, fully massive cross section up to power corrections. The payoff is that neither theory nor experiment changes its working definitions: massless NNLO calculations plus a soft correction match measurements made with standard jet clustering and the usual flavour unfolding. The paper demonstrates the mechanism for b-jets in lepton collisions, single-inclusive b-jet production at the LHC, and Z-plus-b-jet production, and finds the mass logarithms are small enough not to break perturbative convergence through NNLO, while power corrections can be larger than those logarithms.

Core claim

The central claim is captured by a factorisation of leading-power quark-mass effects: the massive-quark cross section equals the massless-quark cross section convoluted with a sequence of soft functions S∅, Sbb, Sbbbb, … that insert infinitesimally soft b-quark pairs into the final state. At NNLO only the no-insertion function S∅ and the one-pair function Sbb are needed; Sbb is determined by the universal double-soft limit of a massive quark-antiquark pair, and S∅ is fixed by the requirement that all the soft functions sum to the identity, so that flavour-blind cross sections are mass-blind. Adding these terms cancels the leftover divergence that standard flavour tagging acquires at NNLO, tu

What carries the argument

The load-bearing object is the set of soft massification functions S, which factorise the leading-power quark-mass dependence out of the cross section. Their key element is the double-soft function for a quark-antiquark pair, built from the universal soft-gluon factors attaching the pair's radiation to the hard partons; it controls how an infinitesimally soft b-quark pair is deposited into the final state and how the jet-clustering then counts flavour. The no-pair function S∅ is not computed directly but obtained by the unitarity condition that all S functions add to one. Final-state collinear mass logarithms are argued to cancel by the standard theorem for cancellation of mass singularities

Load-bearing premise

The construction assumes that, in the flavour modulo-2 scheme with a standard jet algorithm, all final-state collinear and soft-collinear mass logarithms cancel by the standard cancellation theorem for mass singularities, so that only the soft S functions need to be added; the paper asserts this on the basis of an argument rather than proving it.

What would settle it

A fully massive NNLO computation of single-inclusive b-jet production at LHC energies, compared bin-by-bin with the massless-plus-S prediction: any difference larger than expected power corrections (order m_b/pT) would falsify the claim. A lighter-weight check is to verify explicitly, for a triple-collinear configuration involving a gluon and a soft b-quark pair, that the collinear divergence cancels locally in the flavour modulo-2 scheme without an S-function insertion.

Watch this falsifier — get emailed when new claim-graph text bears on it.

If this is right

  • A massless NNLO calculation for flavoured jets, supplemented by the S-function contribution, becomes a leading-power replacement for a fully massive calculation up to power corrections.
  • Standard anti-kT jets with flavour modulo-2 tagging become IRC-safe at NNLO without changing the jet definition, the flavour definition, or the cross section.
  • Experimental analyses keep standard clustering and the usual unfolding from any-flavour to flavour modulo-2; no new algorithm or parameter needs to be adopted.
  • The soft mass logarithms at NNLO scale as αs² ln(m_b²/Q²), are numerically small, and do not spoil perturbative convergence through NNLO.
  • The construction extends beyond NNLO; at N3LO only one-loop integrations in the soft functions are needed, a minor cost compared to full massive amplitudes.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • Inference: if the cancellation of final-state collinear mass logarithms were ever found incomplete for some configuration of a standard jet algorithm, the scheme would miss collinear mass logarithms and the advertised equality with the massive cross section would fail; this is the assumption most worth testing.
  • Inference: the same soft-function language suggests a path to resummation of the non-global flavour-changing logarithms by iterating strict soft limits in a parton-shower style, which the paper sketches but does not develop.
  • Inference: extending the construction to strange quarks would require non-perturbative soft functions fitted to data, a possibility the paper names but leaves unbuilt; this would turn the method from a perturbative fix into a hadronisation-level description.
  • Inference: the paper's finding that power corrections can exceed the mass logarithms implies that at low jet pT or high precision the practical endgame is to compute massive cross sections anyway, with the massless-plus-S approach serving mainly as the high-pT or higher-order shortcut.

Editorial analysis

A structured set of objections, weighed in public.

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

Referee Report

2 major / 5 minor

Summary. The paper proposes a leading-power 'massification' prescription to render standard jet flavour definitions IRC-safe at NNLO. Starting from the observation that the only uncancelled singularities for flavour modulo-2 jets are soft bb-pairs, it defines process-independent soft functions Sbb and S∅ (Eqs. (2.1)-(2.6)) that subtract the massless double-soft limit and add the massive one. Final-state collinear/fragmentation mass logs are claimed to cancel by KLN under modulo-2 flavour, so no FF matching is needed. The implementation in Stripper is tested by A/B/R parameter independence, cancellation of leftover ε poles, independence of the d-dimensional continuation, and a comparison of the LP sum with a fully massive e+e-→ttbar-like calculation; phenomenological NNLO results are presented for Z+b-jet and single-inclusive b-jet production. The paper claims that, up to power corrections, the massless calculation plus S functions reproduces the fully massive cross section.

Significance. Should the leading-power factorization hold, this is a significant practical advance: it allows NNLO predictions for b-jets with standard anti-kT clustering and modulo-2 flavour, removing the need for modified jet/flavour definitions or unfolding to theory-specific schemes. The numerical checks in Section 3 are genuinely strong: the cancellation of the naive ε pole, the parameter-independence of the UV subtraction, and the e+e-→ttbar massive-match test are nontrivial and provide real support for the implementation. The phenomenological studies in Section 4 also illustrate important limitations, especially power corrections. However, the central factorization relies on an unproven KLN cancellation of final-state collinear mass logs for generic jet algorithms, so the significance is conditional.

major comments (2)
  1. [Section 2, 'The case of collinear final state logs ... can be omitted entirely'] The omission of all perturbative fragmentation-function matching is the load-bearing step of the paper. The argument checks two NLO pairs (Figs. 1 and 3) and then concludes, 'By the KLN-theorem, this holds to any order.' KLN guarantees cancellation only for sums over complete sets of degenerate states; it is not automatic for the flavour-sensitive, jet-clustered observable defined by F in Eq. (2.1). In particular, configurations in which the two soft quarks are each collinear to a different hard parton, so that each jet's modulo-2 flavour changes, are not among the two NLO examples. If such configurations produced a non-cancelling ln(m_b^2), Eq. (2.1) would miss it. The numerical tests in Section 3 are consistency tests of the implementation (pole cancellation, A/B/R independence, analytic-continuation independence); the e+e-→ttbar-like test in Fig. 7 uses Durham, not anti-kT, and the ma
  2. [Section 2, Eqs. (2.3)-(2.6) and Section 3] The completeness of the operator set in Eq. (2.1) is assumed rather than derived. Sbb is defined as the massive-minus-massless double-soft limit, and S∅ is fixed by the sum rule Eq. (2.3). This construction ensures that the double-soft singularity is removed by construction, but it does not by itself exclude other leading-power mass-logarithmic corrections at NNLO (e.g. one-loop soft or collinear-soft regions not captured by Sbb/S∅). The numerical checks demonstrate the internal consistency of the implementation and, in Fig. 7, agreement with one fully massive process, but they are not a derivation of the factorization. I would ask the author to state this distinction explicitly and, if possible, to provide a power-counting argument for why the S functions and the standard PDF/α_s decoupling terms exhaust the leading-power mass logarithms through NNLO.
minor comments (5)
  1. [Title and Abstract] The phrase 'IRC-safe jet flavour without modifying anything' overstates the change: the method adds a new S-function contribution and uses the flavour modulo-2 scheme. The more precise claim in the body, 'without modifying the jet definition, the flavour definition, or the cross section', is preferable and should be reflected in the title/abstract.
  2. [Section 3, Fig. 6] The caption should state explicitly that the orange curves are the sum multiplied by 10, and that the plotted differences are for a single choice of A,B,R, since this affects how the cancellation should be read.
  3. [Section 2 and 3] The paper claims applicability to all common jet algorithms but only presents numerical tests for anti-kT and Durham. A sentence explaining why kT and Cambridge-Aachen are covered by the same KLN and soft-factorization arguments would be useful.
  4. [References] Ref. [17] has a malformed DOI ('10.1103/b6pf-rj4h'); please correct it.
  5. [Notation in Eq. (2.1)] The arguments of Sbb are written pb, pb without distinguishing the quark and antiquark; using e.g. pb and pbbar would avoid confusion in the phase-space integrations.

Circularity Check

2 steps flagged

The soft massification is constructed rather than predicted: Sbb is defined as the massive-minus-massless double-soft limit and S∅ is fixed by the normalization sum rule, so the double-soft pole cancellation is built in; independent content remains in the factorization ansatz and the successful full-massive comparison.

specific steps
  1. self definitional [Section 2, after eq. (2.6)]
    "Technically, the S functions should correspond to the difference between the massive and massless cross sections. Therefore Sbb should correspond to the difference between the double-soft limit of the massive and massless cross sections. In this case, the cross section is proportional to Iij(pb, pb, mb) − Iij(pb, pb, 0). This also highlights that the massification removes the double-soft poles from the massless cross section, since the double-soft limit is explicitly subtracted."

    The added Sbb term is defined as exactly the massive-minus-massless double-soft function. Therefore the leading-power massive soft behaviour is inserted by construction rather than derived as a prediction. The abstract's claim that the IRC-unsafe massless cross section 'recovers' the IRC-safe massive one is thus partially true by definition of the added term. What remains non-trivial is the process-independent, colour-correlated factorization of this soft function and the full numerical validation against massive calculations.

  2. self definitional [Section 2, after eq. (2.3), the double-virtual paragraph]
    "Moving on to the double-virtual contribution, it can in principle be computed analytically using the diagram shown in the top-left panel of fig. 4. However, we here refrain from performing this exercise. Instead, we use the relation given in eq. ( 2.3) to obtain it numerically. I.e. after deriving the NNLO expression for Sbb ⊗ σ, we will compute S∅ ⊗ σ by negation and integration over the soft momenta pb and pb, while leaving the final state intact (i.e. without inserting the soft quarks into the final state)."

    The double-virtual soft function S∅ is not derived independently; it is defined as minus the integrated Sbb through the unitarity sum rule (2.2)-(2.3). Consequently, the cancellation of the double-soft pole in the combination massless σ + Sbb + S∅ is enforced by construction. The pole-cancellation test in Fig. 6 (centre) is therefore a consistency check of the implementation, not an independent proof that the scheme is IRC safe. The paper itself concedes that the first three numerical checks are mathematically equivalent and tied to the same ε-pole.

full rationale

The paper does not fit parameters to data, and it does not rest on author-only uniqueness theorems. The central factorisation ansatz (2.1) is asserted by analogy with perturbative fragmentation, and the omission of final-state collinear logs is justified by the external Kinoshita-Lee-Nauenberg theorem; a missing rigorous proof of these points is a correctness/validity concern, not circularity. The double-soft sector, however, is constructive: Sbb is explicitly defined as the massive-minus-massless double-soft limit, and S∅ is fixed by the normalisation sum rule by negation. The removal of the double-soft pole from the massless cross section is therefore built into the added terms rather than predicted. The paper even acknowledges that its first three numerical checks are mathematically equivalent implementation tests related to that pole. What keeps the score moderate is the independent, parameter-free validation against fully massive calculations (fig. 7) and the NLO massive comparisons (fig. 9), which test the factorisation beyond the defining soft limit. Self-citations such as refs. [15-18] and [53] are tool/resummation references and are not load-bearing for the circularity question.

Axiom & Free-Parameter Ledger

1 free parameters · 5 axioms · 0 invented entities

The method introduces no new physical particles or forces. Its main non-standard ingredients are the S functions and the claimed soft-mass factorisation, which are functional objects rather than new entities. The free parameters are only technical regulators whose dependence is shown to cancel.

free parameters (1)
  • UV subtraction parameters A, B, R = A=3, B=2, R=mb (default), checked against A=0, B=1, R=2mb
    Hand-chosen regulators in eq. (2.9); the paper demonstrates cancellation of their dependence in fig. 6, so they are not physical free parameters but do shape the implementation.
axioms (5)
  • domain assumption Soft mass logarithms factorise from the hard cross section via the S-function expansion (eq. 2.1), in analogy with perturbative fragmentation functions.
    The paper states this factorisation has not been discussed before; it is asserted by analogy, with numerical tests as supporting evidence.
  • domain assumption All final-state (soft-)collinear logarithms cancel by KLN when flavour modulo-2 and standard jet algorithms are used, so FFs can be omitted.
    Used to drop collinear mass logs; load-bearing for the claim that only the soft S function is needed.
  • domain assumption The flavour-insensitive sum rule (eq. 2.2): sum over S functions equals identity, so S∅ = 1 - ∫Sbb at NNLO.
    This lets the double-virtual contribution be obtained by negation rather than direct calculation.
  • domain assumption Double-soft factorisation with colour correlations (eqs. 2.4-2.5) applies to massive quark pairs, with Iij(m) obtained from uniform soft and mass scaling.
    Central ingredient of Sbb; follows from soft expansion but is not rederived in detail.
  • domain assumption The class of analytical continuations of 4D observables beyond d=4 is restricted to scalar products of (d-4) components; within this class, continuation dependence cancels.
    Needed for numerical d-dimensional angular integrations; the paper restricts and checks this class.

pith-pipeline@v1.3.0-alltime-deepseek · 26684 in / 13495 out tokens · 138965 ms · 2026-08-03T19:30:59.808541+00:00 · methodology

0 comments
read the original abstract

We derive the leading power quark mass effects in cross sections involving flavour modulo-2 jets at next-to-next-to-leading order (NNLO) in QCD. Including these leading power terms recovers, up to power corrections, the infrared-collinear-safe massive-quark cross section from the infrared-collinear-unsafe massless-quark one. The method is applicable to all common jet algorithms and significantly more practical than computing fully massive cross sections. We explicitly demonstrate the approach for flavoured jets produced in lepton collisions, inclusive $b$-jet production at the LHC and the associated production of a $b$-jet and a $Z$-boson at the LHC. Through NNLO, we do not observe any breakdown of perturbative convergence resulting from the presence of logarithms of the quark mass, though such effects might become significant at higher orders. The most important feature of our approach is that it does not require any changes to the definition of the jet or its flavour, nor does it modify the definition of the cross section. Consequently, the predictions can be compared to measurements performed using standard jet clustering algorithms, provided that jet flavour is assigned according to the flavour modulo-2 scheme or an unfolding to this scheme is performed, without the need for experimental collaborations to adapt their analyses to some new, infrared-collinear-safe definition of jet flavour, as would be the case for most - if not all - solutions presented in the literature thus far. We further demonstrate that power corrections in the quark mass, which are typically neglected in the literature, can be significant.

discussion (0)

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Forward citations

Cited by 2 Pith papers

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score.

  1. Top-associated Higgs-boson production using perturbative fragmentation functions at next-to-leading-order

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    Perturbative fragmentation functions reproduce the leading top-mass dependence of the exact NLO ttH cross section in the hybrid prescription at LHC energies.

  2. Top-associated Higgs-boson production using perturbative fragmentation functions at next-to-leading-order

    hep-ph 2026-05 unverdicted novelty 5.0

    Perturbative fragmentation functions approximate ttH production at NLO and yield reliable results in the hybrid prescription at LHC energies.

Reference graph

Works this paper leans on

57 extracted references · 5 canonical work pages · cited by 1 Pith paper

  1. [1]

    Banfi, G

    A. Banfi, G. P. Salam and G. Zanderighi, Eur. Phys. J. C 47, 113-124 (2006) doi:10.1140/epjc/s2006-02552-4 [arXiv:hep-ph/0601139 [hep-ph]]

  2. [2]

    Cacciari, G

    M. Cacciari, G. P. Salam and G. Soyez, JHEP 04, 063 (2008) doi:10.1088/1126-6708/2008/04/063 [arXiv:0802.1189 [hep-ph]]

  3. [3]

    Catani, Y

    S. Catani, Y. L. Dokshitzer, M. H. Seymour and B. R. Webber, Nucl. Phys. B 406, 187-224 (1993) doi:10.1016/0550-3213(93)90166-M and references therein

  4. [4]

    S. D. Ellis and D. E. Soper, Phys. Rev. D 48, 3160-3166 (1993) doi:10.1103/PhysRevD.48.3160 [arXiv:hep-ph/9305266 [hep-ph]]

  5. [5]

    Y. L. Dokshitzer, G. D. Leder, S. Moretti and B. R. Webber, JHEP 08, 001 (1997) doi:10.1088/1126-6708/1997/08/001 [arXiv:hep-ph/9707323 [hep-ph]]

  6. [6]

    Wobisch and T

    M. Wobisch and T. Wengler, [arXiv:hep-ph/9907280 [hep-ph]]. – 30 –

  7. [7]

    Caola, R

    F. Caola, R. Grabarczyk, M. L. Hutt, G. P. Salam, L. Scyboz and J. Thaler, Phys. Rev. D 108, no.9, 094010 (2023) doi:10.1103/PhysRevD.108.094010 [arXiv:2306.07314 [hep-ph]]

  8. [8]

    ’t Hooft and M

    G. ’t Hooft and M. J. G. Veltman, Nucl. Phys. B 44, 189-213 (1972) doi:10.1016/0550-3213(72)90279-9

  9. [9]

    Behring, S

    A. Behring, S. Caletti, F. Giuli, R. Grabarczyk, A. Hinzmann, A. Huss, J. Huston, E. D. Lesser, S. Marzani and D. Napoletano, et al. JHEP 09, 149 (2025) doi:10.1007/JHEP09(2025)149 [arXiv:2506.13449 [hep-ph]]

  10. [10]

    Caletti, A

    S. Caletti, A. J. Larkoski, S. Marzani and D. Reichelt, Eur. Phys. J. C 82, no.7, 632 (2022) doi:10.1140/epjc/s10052-022-10568-7 [arXiv:2205.01109 [hep-ph]]

  11. [11]

    Caletti, A

    S. Caletti, A. J. Larkoski, S. Marzani and D. Reichelt, JHEP 10, 158 (2022) doi:10.1007/JHEP10(2022)158 [arXiv:2205.01117 [hep-ph]]

  12. [12]

    Czakon, A

    M. Czakon, A. Mitov and R. Poncelet, JHEP 04, 138 (2023) doi:10.1007/JHEP04(2023)138 [arXiv:2205.11879 [hep-ph]]

  13. [13]

    Gauld, A

    R. Gauld, A. Huss and G. Stagnitto, Phys. Rev. Lett. 130, no.16, 161901 (2023) [erratum: Phys. Rev. Lett. 132, no.15, 159901 (2024)] doi:10.1103/PhysRevLett.130.161901 [arXiv:2208.11138 [hep-ph]]

  14. [14]

    A. J. Larkoski, [arXiv:2510.06031 [hep-ph]]

  15. [15]

    Czakon, T

    M. Czakon, T. Generet, A. Mitov and R. Poncelet, JHEP 10, 216 (2021) doi:10.1007/JHEP10(2021)216 [arXiv:2102.08267 [hep-ph]]

  16. [16]

    Czakon, T

    M. Czakon, T. Generet, A. Mitov and R. Poncelet, JHEP 03, 251 (2023) doi:10.1007/JHEP03(2023)251 [arXiv:2210.06078 [hep-ph]]

  17. [17]

    Czakon, T

    M. Czakon, T. Generet, A. Mitov and R. Poncelet, Phys. Rev. Lett. 135, no.16, 16 (2025) doi:10.1103/b6pf-rj4h [arXiv:2411.09684 [hep-ph]]

  18. [18]

    Generet, R

    T. Generet, R. Poncelet and M. Muškinja, [arXiv:2510.24525 [hep-ph]]

  19. [19]

    Buonocore, S

    L. Buonocore, S. Devoto, S. Kallweit, J. Mazzitelli, L. Rottoli and C. Savoini, Phys. Rev. D 107, no.7, 074032 (2023) doi:10.1103/PhysRevD.107.074032 [arXiv:2212.04954 [hep-ph]]

  20. [20]

    Weinberg, Phys

    S. Weinberg, Phys. Lett. B 91, 51-55 (1980) doi:10.1016/0370-2693(80)90660-7

  21. [21]

    B. A. Ovrut and H. J. Schnitzer, Phys. Lett. B 100, 403-406 (1981) doi:10.1016/0370-2693(81)90146-5

  22. [22]

    M. A. G. Aivazis, J. C. Collins, F. I. Olness and W. K. Tung, Phys. Rev. D 50, 3102-3118 (1994) doi:10.1103/PhysRevD.50.3102 [arXiv:hep-ph/9312319 [hep-ph]]

  23. [23]

    M. Buza, Y. Matiounine, J. Smith, R. Migneron and W. L. van Neerven, Nucl. Phys. B 472, 611-658 (1996) doi:10.1016/0550-3213(96)00228-3 [arXiv:hep-ph/9601302 [hep-ph]]

  24. [24]

    M. Buza, Y. Matiounine, J. Smith and W. L. van Neerven, Eur. Phys. J. C 1, 301-320 (1998) doi:10.1007/BF01245820 [arXiv:hep-ph/9612398 [hep-ph]]

  25. [25]

    Bierenbaum, J

    I. Bierenbaum, J. Blumlein and S. Klein, Nucl. Phys. B 780, 40-75 (2007) doi:10.1016/j.nuclphysb.2007.04.030 [arXiv:hep-ph/0703285 [hep-ph]]

  26. [26]

    Bierenbaum, J

    I. Bierenbaum, J. Blumlein, S. Klein and C. Schneider, Nucl. Phys. B 803, 1-41 (2008) doi:10.1016/j.nuclphysb.2008.05.016 [arXiv:0803.0273 [hep-ph]]. – 31 –

  27. [27]

    Bierenbaum, J

    I. Bierenbaum, J. Blumlein and S. Klein, Phys. Lett. B 672, 401-406 (2009) doi:10.1016/j.physletb.2009.01.057 [arXiv:0901.0669 [hep-ph]]

  28. [28]

    Mele and P

    B. Mele and P. Nason, Nucl. Phys. B 361, 626-644 (1991) [erratum: Nucl. Phys. B 921, 841-842 (2017)] doi:10.1016/0550-3213(91)90597-Q

  29. [29]

    Melnikov and A

    K. Melnikov and A. Mitov, Phys. Rev. D 70, 034027 (2004) doi:10.1103/PhysRevD.70.034027 [arXiv:hep-ph/0404143 [hep-ph]]

  30. [30]

    Mitov, Phys

    A. Mitov, Phys. Rev. D 71, 054021 (2005) doi:10.1103/PhysRevD.71.054021 [arXiv:hep-ph/0410205 [hep-ph]]

  31. [31]

    Cacciari, P

    M. Cacciari, P. Nason and C. Oleari, JHEP 10, 034 (2005) doi:10.1088/1126-6708/2005/10/034 [arXiv:hep-ph/0504192 [hep-ph]]

  32. [32]

    Neubert, [arXiv:0706.2136 [hep-ph]]

    M. Neubert, [arXiv:0706.2136 [hep-ph]]

  33. [33]

    Kinoshita, J

    T. Kinoshita, J. Math. Phys. 3, 650-677 (1962) doi:10.1063/1.1724268

  34. [34]

    T. D. Lee and M. Nauenberg, Phys. Rev. 133, B1549-B1562 (1964) doi:10.1103/PhysRev.133.B1549

  35. [35]

    Czakon and D

    M. Czakon and D. Heymes, Nucl. Phys. B 890, 152-227 (2014) doi:10.1016/j.nuclphysb.2014.11.006 [arXiv:1408.2500 [hep-ph]]

  36. [36]

    Czakon, Phys

    M. Czakon, Phys. Lett. B 693, 259-268 (2010) doi:10.1016/j.physletb.2010.08.036 [arXiv:1005.0274 [hep-ph]]

  37. [37]

    Czakon, Nucl

    M. Czakon, Nucl. Phys. B 849, 250-295 (2011) doi:10.1016/j.nuclphysb.2011.03.020 [arXiv:1101.0642 [hep-ph]]

  38. [38]

    Czakon, A

    M. Czakon, A. van Hameren, A. Mitov and R. Poncelet, JHEP 10, 262 (2019) doi:10.1007/JHEP10(2019)262 [arXiv:1907.12911 [hep-ph]]

  39. [39]

    Dasgupta and G

    M. Dasgupta and G. P. Salam, Phys. Lett. B 512, 323-330 (2001) doi:10.1016/S0370-2693(01)00725-0 [arXiv:hep-ph/0104277 [hep-ph]]

  40. [40]

    Banfi, G

    A. Banfi, G. Marchesini and G. Smye, JHEP 08, 006 (2002) doi:10.1088/1126-6708/2002/08/006 [arXiv:hep-ph/0206076 [hep-ph]]

  41. [41]

    R. D. Ball et al. [NNPDF], Eur. Phys. J. C 77, no.10, 663 (2017) doi:10.1140/epjc/s10052-017-5199-5 [arXiv:1706.00428 [hep-ph]]

  42. [42]

    Buckley, J

    A. Buckley, J. Ferrando, S. Lloyd, K. Nordström, B. Page, M. Rüfenacht, M. Schönherr and G. Watt, Eur. Phys. J. C 75, 132 (2015) [arXiv:1412.7420 [hep-ph]]

  43. [43]

    R. D. Ball et al. [PDF4LHC Working Group], J. Phys. G 49, no.8, 080501 (2022) doi:10.1088/1361-6471/ac7216 [arXiv:2203.05506 [hep-ph]]

  44. [44]

    Cacciari, M

    M. Cacciari, M. Greco and P. Nason, JHEP 05, 007 (1998) doi:10.1088/1126-6708/1998/05/007 [arXiv:hep-ph/9803400 [hep-ph]]

  45. [45]

    Wetzel, Nucl

    W. Wetzel, Nucl. Phys. B 196, 259-272 (1982) doi:10.1016/0550-3213(82)90038-4

  46. [46]

    Bernreuther and W

    W. Bernreuther and W. Wetzel, Nucl. Phys. B 197, 228-236 (1982) [erratum: Nucl. Phys. B 513, 758-758 (1998)] doi:10.1016/0550-3213(82)90288-7

  47. [47]

    Bernreuther, Annals Phys

    W. Bernreuther, Annals Phys. 151, 127 (1983) doi:10.1016/0003-4916(83)90317-2 – 32 –

  48. [48]

    Bernreuther, Z

    W. Bernreuther, Z. Phys. C 20, 331-333 (1983) doi:10.1007/BF01407825

  49. [49]

    S. A. Larin, T. van Ritbergen and J. A. M. Vermaseren, Nucl. Phys. B 438, 278-306 (1995) doi:10.1016/0550-3213(94)00574-X [arXiv:hep-ph/9411260 [hep-ph]]

  50. [50]

    Currie, E

    J. Currie, E. W. N. Glover and J. Pires, Phys. Rev. Lett. 118, no.7, 072002 (2017) doi:10.1103/PhysRevLett.118.072002 [arXiv:1611.01460 [hep-ph]]

  51. [51]

    Currie, A

    J. Currie, A. Gehrmann-De Ridder, T. Gehrmann, E. W. N. Glover, A. Huss and J. Pires, JHEP 10, 155 (2018) doi:10.1007/JHEP10(2018)155 [arXiv:1807.03692 [hep-ph]]

  52. [52]

    Bellm, A

    J. Bellm, A. Buckley, X. Chen, A. Gehrmann-De Ridder, T. Gehrmann, N. Glover, A. Huss, J. Pires, S. Höche and J. Huston, et al. Eur. Phys. J. C 80, no.2, 93 (2020) doi:10.1140/epjc/s10052-019-7574-x [arXiv:1903.12563 [hep-ph]]

  53. [53]

    Generet, K

    T. Generet, K. Lee, I. Moult, R. Poncelet and X. Zhang, JHEP 08, 015 (2025) doi:10.1007/JHEP08(2025)015 [arXiv:2503.21866 [hep-ph]]

  54. [54]

    Gao and H

    J. Gao and H. X. Zhu, Phys. Rev. D 90, no.11, 114022 (2014) doi:10.1103/PhysRevD.90.114022 [arXiv:1408.5150 [hep-ph]]

  55. [55]

    Gao and H

    J. Gao and H. X. Zhu, Phys. Rev. Lett. 113, no.26, 262001 (2014) doi:10.1103/PhysRevLett.113.262001 [arXiv:1410.3165 [hep-ph]]

  56. [56]

    L. Chen, O. Dekkers, D. Heisler, W. Bernreuther and Z. G. Si, JHEP 12, 098 (2016) doi:10.1007/JHEP12(2016)098 [arXiv:1610.07897 [hep-ph]]

  57. [57]

    Kleiss, W

    R. Kleiss, W. J. Stirling and S. D. Ellis, Comput. Phys. Commun. 40, 359 (1986) doi:10.1016/0010-4655(86)90119-0 – 33 –