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arxiv: 2605.07618 · v1 · submitted 2026-05-08 · ✦ hep-ph

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New Determinations of the Charm and Bottom Quark Masses Using QCD Quarkonium Sum Rules

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Pith reviewed 2026-05-11 02:30 UTC · model grok-4.3

classification ✦ hep-ph
keywords QCD sum rulesheavy quark massesPrinciple of Maximum Conformalityquarkonium correlatorsperturbative QCD correctionsPadé approximationcharm quark massbottom quark mass
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The pith

Applying the characteristic operator extension of the Principle of Maximum Conformality to QCD quarkonium sum rules eliminates renormalization ambiguities and yields precise charm and bottom quark masses.

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

The paper reanalyzes perturbative QCD corrections to the correlation functions of heavy-quark currents using the Principle of Maximum Conformality combined with a characteristic operator approach. This method absorbs nonconformal terms to produce a scheme- and scale-independent conformal series for the sum-rule moments. The authors then use Padé approximants to estimate the missing fourth-order terms and extract the MS-bar masses from specific moments of the charmed pseudoscalar and bottom vector correlators. These determinations agree with experimental world averages to within less than one standard deviation, providing tighter constraints for particle physics phenomenology.

Core claim

Using the CO-PMC approach on the O(α_s^3) pQCD corrections to M_n,q^{X,th}, the perturbative series becomes strictly conformal and independent of renormalization scheme and scale. Combined with Padé estimates for N4LO, this leads to m_c(m_c) = 1275.8 ± 0.4 MeV from M_{2,c}^P and m_b(m_b) = 4177.0 ± 7.2 MeV from M_{1,b}^V, both consistent with PDG averages within 1σ.

What carries the argument

The characteristic operator (CO) extension of PMC, which simultaneously fixes the effective coupling and quark mass by absorbing β_i and γ_i terms through renormalization group equations to generate a conformal perturbative expansion.

If this is right

  • The extracted quark masses serve as improved inputs for calculations of quarkonium properties and heavy-flavor physics.
  • Scale-independent results allow for more reliable comparisons between theory and experiment in sum-rule analyses.
  • The Padé method provides a systematic way to estimate unknown higher-order perturbative contributions in similar processes.
  • Application to other moments or channels could further refine the mass values or extract other parameters like decay constants.

Where Pith is reading between the lines

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

  • If the CO-PMC procedure generalizes, it could be used to remove perturbative ambiguities in other QCD observables beyond sum rules.
  • The close agreement with PDG suggests that non-perturbative contributions or experimental inputs now limit the precision rather than the perturbative series itself.
  • Future lattice QCD calculations of the same correlators could test the consistency of the perturbative treatment independent of sum-rule assumptions.

Load-bearing premise

The characteristic operator extension of PMC produces a strictly scheme- and scale-independent conformal series, and Padé approximants accurately estimate the unknown N4LO terms without large uncontrolled errors.

What would settle it

A full N4LO calculation of the quarkonium correlation functions that differs substantially from the Padé predictions, or a new experimental determination of the charm or bottom quark mass lying outside the stated uncertainty ranges.

Figures

Figures reproduced from arXiv: 2605.07618 by Hua Zhou, Qing Yu, Xing-Gang Wu.

Figure 1
Figure 1. Figure 1: FIG. 1: The moments [PITH_FULL_IMAGE:figures/full_fig_p008_1.png] view at source ↗
Figure 2
Figure 2. Figure 2: FIG. 2: The moments [PITH_FULL_IMAGE:figures/full_fig_p009_2.png] view at source ↗
Figure 3
Figure 3. Figure 3: FIG. 3: The moments [PITH_FULL_IMAGE:figures/full_fig_p011_3.png] view at source ↗
Figure 4
Figure 4. Figure 4: FIG. 4: The moments [PITH_FULL_IMAGE:figures/full_fig_p012_4.png] view at source ↗
read the original abstract

We reanalyze the perturbative QCD (pQCD) corrections to quarkonium QCD sum rules and extract the heavy quark masses $\overline{m}_{q}(\overline{m}_{q})$ ($q=c,b$). At present, the pQCD corrections to the correlation functions of two heavy-quark pseudoscalar and vector currents at zero momentum transfer, denoted as $M_{n,q}^{X,\rm th}$ ($X = P, V$), are calculated up to the $\mathcal{O}(\alpha_s^3)$ order. These corrections exhibit significant renormalization scheme and scale dependence, which introduces large theoretical uncertainties and deteriorates the precision of heavy quark mass determinations. In this work, we eliminate the renormalization scheme and scale ambiguities in the perturbative part of $M_{n,q}^{X,\rm th}$ by adopting the Principle of Maximum Conformality (PMC) within the characteristic operator (CO) approach. The CO approach, a novel extension of the standard PMC procedure, simultaneously determines the effective coupling $\alpha_s(Q_*)$ and the effective quark mass $\overline{m}_q(Q_*)$. It systematically absorbs the nonconformal $\{\beta_i\}$-terms and $\{\gamma_i\}$-terms via the renormalization group equations, yielding a strictly scheme- and scale-independent conformal perturbative series. Based on the improved PMC conformal series, we further provide reliable estimates for the unknown $\mathrm{N^4LO}$ contributions using the Pad\'e approximation method. The final predicted heavy quark masses in the $\overline{\mathrm{MS}}$ scheme read: $\overline{m}_c(\overline{m}_c)=1275.8\pm 0.4~\text{MeV}$, extracted from the second moment of the charmed pseudoscalar correlator $M_{2,c}^{P}$; and $\overline{m}_b(\overline{m}_b) = 4177.0 \pm 7.2~\text{MeV}$, extracted from the first moment of the bottom vector correlator $M_{1,b}^{V}$. Both results agree well with the PDG world averages with deviations smaller than $1\sigma$.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

1 major / 1 minor

Summary. The paper reanalyzes pQCD corrections to the two-point correlation functions of heavy-quark pseudoscalar and vector currents up to O(α_s^3) in quarkonium sum rules. It applies the Principle of Maximum Conformality (PMC) extended via the characteristic operator (CO) approach to absorb all β- and γ-dependent nonconformal terms, yielding a strictly scheme- and scale-independent conformal series. Unknown N4LO contributions are estimated via Padé approximants. The charm mass is extracted from the second moment of the pseudoscalar correlator as m_c(m_c)=1275.8±0.4 MeV and the bottom mass from the first moment of the vector correlator as m_b(m_b)=4177.0±7.2 MeV, both in the MS-bar scheme, with results agreeing with PDG averages to better than 1σ.

Significance. If the CO-PMC procedure produces a genuinely conformal series free of residual scale dependence and the Padé estimates prove accurate, the work would deliver high-precision heavy-quark mass determinations with substantially reduced theoretical uncertainties relative to conventional scale-variation analyses. The sub-MeV error on m_c and the close PDG agreement would represent a notable advance for QCD sum-rule phenomenology, provided the error budget is robust.

major comments (1)
  1. [Abstract] Abstract: The final results m_c(m_c)=1275.8±0.4 MeV and m_b(m_b)=4177.0±7.2 MeV are obtained only after replacing the unknown N4LO coefficient in the CO-PMC series by a Padé approximant. No cross-validation is reported (e.g., applying the same Padé procedure to predict the already-known N3LO coefficient and comparing it with its explicit value). Because QCD series are subject to renormalon-induced factorial growth, an untested Padé extrapolation can introduce an error comparable to or larger than the quoted 0.4 MeV uncertainty on m_c; this directly affects the claimed precision and must be addressed.
minor comments (1)
  1. [Abstract] The abstract refers to 'the second moment of the charmed pseudoscalar correlator M_{2,c}^P' and 'the first moment of the bottom vector correlator M_{1,b}^V' without stating the explicit definitions or the rationale for selecting these particular moments over others; a brief clarification would aid readability.

Simulated Author's Rebuttal

1 responses · 0 unresolved

We thank the referee for the careful reading of our manuscript and the constructive comment. We address the major point raised below and outline the revisions we will make.

read point-by-point responses
  1. Referee: [Abstract] Abstract: The final results m_c(m_c)=1275.8±0.4 MeV and m_b(m_b)=4177.0±7.2 MeV are obtained only after replacing the unknown N4LO coefficient in the CO-PMC series by a Padé approximant. No cross-validation is reported (e.g., applying the same Padé procedure to predict the already-known N3LO coefficient and comparing it with its explicit value). Because QCD series are subject to renormalon-induced factorial growth, an untested Padé extrapolation can introduce an error comparable to or larger than the quoted 0.4 MeV uncertainty on m_c; this directly affects the claimed precision and must be addressed.

    Authors: We thank the referee for highlighting this issue. The CO-PMC procedure, through the characteristic operator approach, absorbs all β- and γ-dependent nonconformal terms into the effective coupling and mass scales, producing a strictly conformal perturbative series. Renormalon effects, which drive factorial growth in conventional QCD expansions, are associated with these nonconformal terms and are therefore eliminated; the remaining conformal series exhibits improved convergence properties that make Padé extrapolation more reliable than in the standard case. We acknowledge that an explicit cross-validation—applying the Padé approximant to predict the known N3LO coefficient from lower orders and comparing it to the exact value—was not reported in the original manuscript. We will add this validation (including quantitative comparison) to the revised version, together with a clearer explanation of how the spread among different Padé approximants is used to estimate the N4LO uncertainty and how it is incorporated into the final error budget. These additions will directly address the concern about the robustness of the quoted precision. revision: yes

Circularity Check

0 steps flagged

No circularity in the quark mass extraction via CO-PMC sum rules

full rationale

The paper reorganizes the known O(α_s^3) perturbative corrections to the quarkonium correlator moments using the CO extension of PMC, which by construction absorbs nonconformal β_i and γ_i terms via the RGE to produce a scale- and scheme-independent conformal series. It then applies Padé approximants to estimate the unknown N^4LO coefficient and extracts the MS-bar masses by matching the resulting theoretical moments M_n^th to experimental inputs. This matching step determines the mass values from external data rather than by internal definition or by renaming a fitted parameter as a prediction. No self-definitional reduction, fitted-input-called-prediction, or load-bearing self-citation chain is present; the central claim retains independent content from the data fit and the perturbative reorganization.

Axiom & Free-Parameter Ledger

0 free parameters · 0 axioms · 0 invented entities

Abstract provides no explicit list of free parameters or ad-hoc assumptions; the method assumes standard perturbative QCD and the validity of the PMC absorption procedure, but details are unavailable.

pith-pipeline@v0.9.0 · 5689 in / 1243 out tokens · 52475 ms · 2026-05-11T02:30:09.175380+00:00 · methodology

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Works this paper leans on

114 extracted references · 114 canonical work pages

  1. [1]

    Weinberg, Physica A96, no.1-2, 327-340 (1979)

    S. Weinberg, Physica A96, no.1-2, 327-340 (1979)

  2. [2]

    Gasser and H

    J. Gasser and H. Leutwyler, Annals Phys.158, 142 (1984)

  3. [3]

    Pich, Rept

    A. Pich, Rept. Prog. Phys.58, 563-610 (1995)

  4. [4]

    Weinberg, Trans

    S. Weinberg, Trans. New York Acad. Sci.38, 185-201 (1977)

  5. [5]

    J. O. Andersen, Q. Yu and H. Zhou, Phys. Rev. D109, 034022 (2024)

  6. [6]

    Del Debbio and A

    L. Del Debbio and A. Ramos, [arXiv:2101.04762 [hep- lat]]

  7. [7]

    Aokiet al.[Flavour Lattice Averaging Group (FLAG)], Eur

    Y. Aokiet al.[Flavour Lattice Averaging Group (FLAG)], Eur. Phys. J. C82, 869 (2022)

  8. [8]

    D. J. Gross and F. Wilczek, Phys. Rev. Lett.30, 1343- 1346 (1973)

  9. [9]

    H. D. Politzer, Phys. Rev. Lett.30, 1346-1349 (1973)

  10. [10]

    V. A. Novikov, L. B. Okun, M. A. Shifman, A. I. Vain- shtein, M. B. Voloshin and V. I. Zakharov, Phys. Rept. 41(1978), 1-133

  11. [11]

    L. J. Reinders, H. Rubinstein and S. Yazaki, Phys. Rept. 127, 1 (1985)

  12. [12]

    J. H. K¨ uhn and M. Steinhauser, Nucl. Phys. B619, 588-602 (2001) [erratum: Nucl. Phys. B640, 415-415 (2002)]

  13. [13]

    J. H. K¨ uhn, M. Steinhauser and C. Sturm, Nucl. Phys. B778, 192-215 (2007)

  14. [14]

    M. A. Shifman, A. I. Vainshtein and V. I. Zakharov, Nucl. Phys. B147(1979), 385-447

  15. [15]

    Maezawa and P

    Y. Maezawa and P. Petreczky, Phys. Rev. D94, 034507 (2016)

  16. [16]

    Petreczky and J

    P. Petreczky and J. H. Weber, Phys. Rev. D100, 034519 (2019)

  17. [17]

    Allisonet al.[HPQCD], Phys

    I. Allisonet al.[HPQCD], Phys. Rev. D78, 054513 (2008)

  18. [18]

    McNeile, C

    C. McNeile, C. T. H. Davies, E. Follana, K. Hornbostel and G. P. Lepage, Phys. Rev. D82, 034512 (2010)

  19. [19]

    Petreczky and J

    P. Petreczky and J. H. Weber, Eur. Phys. J. C82, 64 (2022)

  20. [20]

    Nakayama, B

    K. Nakayama, B. Fahy and S. Hashimoto, Phys. Rev. D 94, 054507 (2016)

  21. [21]

    M. A. Shifman, A. I. Vainshtein and V. I. Zakharov, Nucl. Phys. B147(1979), 448-518

  22. [22]

    A. O. G. Kallen and A. Sabry, Kong. Dan. Vid. Sel. Mat. Fys. Med.29(1955)

  23. [23]

    K. G. Chetyrkin, J. H. Kuhn and M. Steinhauser, Phys. Lett. B371(1996), 93-98

  24. [24]

    K. G. Chetyrkin, J. H. Kuhn and M. Steinhauser, Nucl. Phys. B482(1996), 213-240

  25. [25]

    Boughezal, M

    R. Boughezal, M. Czakon and T. Schutzmeier, Nucl. Phys. B Proc. Suppl.160(2006), 160-164

  26. [26]

    Czakon and T

    M. Czakon and T. Schutzmeier, JHEP07(2008), 001

  27. [27]

    Maier, P

    A. Maier, P. Maierhofer and P. Marquard, Nucl. Phys. B797(2008), 218-242

  28. [28]

    K. G. Chetyrkin, J. H. Kuhn and C. Sturm, Eur. Phys. J. C48(2006), 107-110

  29. [29]

    Boughezal, M

    R. Boughezal, M. Czakon and T. Schutzmeier, Phys. Rev. D74(2006), 074006

  30. [30]

    Maier, P

    A. Maier, P. Maierhofer and P. Marquard, Phys. Lett. B669(2008), 88-91

  31. [31]

    Maier, P

    A. Maier, P. Maierhofer, P. Marquard and A. V. Smirnov, Nucl. Phys. B824(2010), 1-18

  32. [32]

    Maier and P

    A. Maier and P. Marquard, Phys. Rev. D97(2018), 056016

  33. [33]

    A. H. Hoang, V. Mateu and S. Mohammad Zebarjad, Nucl. Phys. B813(2009), 349-369

  34. [34]

    Y. Kiyo, A. Maier, P. Maierhofer and P. Marquard, Nucl. Phys. B823(2009), 269-287. 20

  35. [35]

    Greynat and S

    D. Greynat and S. Peris, Phys. Rev. D82(2010), 034030 [erratum: Phys. Rev. D82(2010), 119907]

  36. [36]

    Boito, V

    D. Boito, V. Mateu and M. V. Rodrigues, JHEP08 (2021), 027

  37. [37]

    Signer, Phys

    A. Signer, Phys. Lett. B672, 333-338 (2009)

  38. [38]

    Signer, Phys

    A. Signer, Phys. Lett. B654, 206-214 (2007)

  39. [39]

    D. J. Gross and A. Neveu, Phys. Rev. D10, 3235 (1974)

  40. [40]

    B. E. Lautrup, Phys. Lett. B69, 109-111 (1977)

  41. [41]

    Beneke, Phys

    M. Beneke, Phys. Rept.317, 1-142 (1999)

  42. [42]

    Dehnadi, A

    B. Dehnadi, A. H. Hoang and V. Mateu, JHEP08, 155 (2015)

  43. [43]

    Dehnadi, A

    B. Dehnadi, A. H. Hoang, V. Mateu and S. M. Zebarjad, JHEP09, 103 (2013)

  44. [44]

    Petermann, Helv

    A. Petermann, Helv. Phys. Acta26, 499 (1953)

  45. [45]

    C. G. Callan, Jr., Phys. Rev. D2, 1541 (1970)

  46. [46]

    Symanzik, Commun

    K. Symanzik, Commun. Math. Phys.18, 227 (1970)

  47. [47]

    Peterman, Phys

    A. Peterman, Phys. Rept.53, 157 (1979)

  48. [48]

    S. J. Brodsky and X. G. Wu, Phys. Rev. D85, 034038 (2012)

  49. [49]

    S. J. Brodsky and X. G. Wu, Phys. Rev. Lett.109, 042002 (2012)

  50. [50]

    Mojaza, S

    M. Mojaza, S. J. Brodsky and X. G. Wu, Phys. Rev. Lett.110, 192001 (2013)

  51. [51]

    S. J. Brodsky, M. Mojaza and X. G. Wu, Phys. Rev. D 89, 014027 (2014)

  52. [52]

    X. G. Wu, Y. Ma, S. Q. Wang, H. B. Fu, H. H. Ma, S. J. Brodsky and M. Mojaza, Rep. Prog. Phys.78, 126201 (2015)

  53. [53]

    X. G. Wu, S. Q. Wang and S. J. Brodsky, Front. Phys. 11, 111201 (2016)

  54. [54]

    X. G. Wu, J. M. Shen, B. L. Du, X. D. Huang, S. Q. Wang and S. J. Brodsky, Prog. Part. Nucl. Phys. 108, 103706 (2019)

  55. [55]

    J. Yan, S. J. Brodsky, L. Di Giustino, P. G. Ratcliffe, S. Wang, S. Q. Wang, X. Wu and X. G. Wu, Symmetry 17, 411 (2025)

  56. [56]

    S. J. Brodsky and L. Di Giustino, Phys. Rev. D86, 085026 (2012)

  57. [57]

    X. C. Zheng, X. G. Wu, S. Q. Wang, J. M. Shen and Q. L. Zhang, JHEP10, 117 (2013)

  58. [58]

    J. M. Shen, X. G. Wu, B. L. Du and S. J. Brodsky, Phys. Rev. D95, 094006 (2017)

  59. [59]

    X. G. Wu, J. M. Shen, B. L. Du and S. J. Brodsky, Phys. Rev. D97, 094030 (2018)

  60. [60]

    J. M. Shen, B. H. Qin, J. Yan, S. Q. Wang and X. G. Wu, JHEP07, 109 (2023)

  61. [61]

    S. Q. Wang, C. Q. Luo, X. G. Wu, J. M. Shen and L. Di Giustino, JHEP09, 137 (2022)

  62. [62]

    Q. Yu, H. Zhou, X. D. Huang, J. M. Shen and X. G. Wu, Chin. Phys. Lett.39, 071201 (2022)

  63. [63]

    H. Y. Bi, X. G. Wu, Y. Ma, H. H. Ma, S. J. Brodsky and M. Mojaza, Phys. Lett. B748, 13-18 (2015)

  64. [64]

    S. Q. Wang, X. G. Wu, X. C. Zheng, G. Chen and J. M. Shen, J. Phys. G41, 075010 (2014)

  65. [65]

    Q. Yu, X. G. Wu, S. Q. Wang, X. D. Huang, J. M. Shen and J. Zeng, Chin. Phys. C43, 093102 (2019)

  66. [66]

    X. D. Huang, X. G. Wu, J. Zeng, Q. Yu, X. C. Zheng and S. Xu, Phys. Rev. D101, 114024 (2020)

  67. [67]

    X. D. Huang, X. G. Wu, X. C. Zheng, J. Yan, Z. F. Wu and H. H. Ma, Chin. Phys. C48, 053113 (2024)

  68. [68]

    S. Y. Ma, X. D. Huang, X. C. Zheng and X. G. Wu, Chin. Phys. Lett.41, 101201 (2024)

  69. [69]

    J. Yan, X. G. Wu, J. M. Shen, X. D. Huang and Z. F. Wu, JHEP04, 184 (2025)

  70. [70]

    B. L. Du, X. G. Wu, J. M. Shen and S. J. Brodsky, Eur. Phys. J. C79, 182 (2019)

  71. [71]

    J. M. Shen, Z. J. Zhou, S. Q. Wang, J. Yan, Z. F. Wu, X. G. Wu and S. J. Brodsky, Eur. Phys. J. C83, no.4, 326 (2023)

  72. [72]

    K. G. Chetyrkin, Phys. Lett. B404, 161-165 (1997)

  73. [73]

    J. A. M. Vermaseren, S. A. Larin and T. van Ritbergen, Phys. Lett. B405, 327-333 (1997)

  74. [74]

    K. G. Chetyrkin, Nucl. Phys. B710, 499 (2005)

  75. [75]

    Czakon, Nucl

    M. Czakon, Nucl. Phys. B710, 485 (2005)

  76. [76]

    P. A. Baikov, K. G. Chetyrkin and J. H. K¨ uhn, JHEP 10, 076 (2014)

  77. [77]

    P. A. Baikov, K. G. Chetyrkin and J. H. K¨ uhn, Phys. Rev. Lett.118, no.8, 082002 (2017)

  78. [78]

    Herzog, B

    F. Herzog, B. Ruijl, T. Ueda, J. A. M. Vermaseren and A. Vogt, JHEP02, 090 (2017)

  79. [79]

    B. L. Ioffe, Prog. Part. Nucl. Phys.56(2006), 232-277

  80. [80]

    Narison and R

    S. Narison and R. Tarrach, Phys. Lett. B125(1983), 217-222

Showing first 80 references.