Muon and electron g − 2 and lepton masses in flavor models


The stringent experimental bound on μ → eγ is compatible with a simultaneous and sizable new physics contribution to the electron and muon anomalous magnetic moments (g − 2) (ℓ = e, μ), only if we assume a non-trivial flavor structure of the dipole operator coefficients. We propose a mechanism in which the realization of the (g − 2) correction is manifestly related to the mass generation through a flavor symmetry. A radiative flavon correction to the fermion mass gives a contribution to the anomalous magnetic moment. In this framework, we introduce a chiral enhancement from a non-trivial \( \mathcal{O} \)(1) quartic coupling of the scalar potential. We show that the muon and electron anomalies can be simultaneously explained in a vast region of the parameter space with predicted vector-like mediators of masses as large as ∈ [0.6, 2.5] TeV.

A preprint version of the article is available at ArXiv.


  1. [1]

    J. Albrecht, S. Reichert and D. van Dyk, Status of rare exclusive B meson decays in 2018, Int. J. Mod. Phys.A 33 (2018) 1830016 [arXiv:1806.05010] [INSPIRE].

    ADS  Article  Google Scholar 

  2. [2]

    Y. Li and C.-D. Lü, Recent anomalies in B physics, Sci. Bull.63 (2018) 267 [arXiv:1808.02990] [INSPIRE].

  3. [3]

    S. Bifani, S. Descotes-Genon, A. Romero Vidal and M.-H. Schune, Review of lepton universality tests in B decays, J. Phys.G 46 (2019) 023001 [arXiv:1809.06229] [INSPIRE].

  4. [4]

    Muon g-2 collaboration, Final report of the muon E821 anomalous magnetic moment measurement at BNL, Phys. Rev.D 73 (2006) 072003 [hep-ex/0602035] [INSPIRE].

  5. [5]

    M. Davier, A. Hoecker, B. Malaescu and Z. Zhang, Reevaluation of the hadronic contributions to the muon g − 2 and to α(MZ), Eur. Phys. J.C 71 (2011) 1515 [Erratum ibid.C 72 (2012) 1874] [arXiv:1010.4180] [INSPIRE].

  6. [6]

    M. Davier, A. Hoecker, B. Malaescu and Z. Zhang, Reevaluation of the hadronic vacuum polarisation contributions to the Standard Model predictions of the muon g − 2 and \( \alpha \left({m}_Z^2\right) \)using newest hadronic cross-section data, Eur. Phys. J.C 77 (2017) 827 [arXiv:1706.09436] [INSPIRE].

  7. [7]

    A. Keshavarzi, D. Nomura and T. Teubner, Muon g − 2 and \( \alpha \left({m}_Z^2\right) \): a new data-based analysis, Phys. Rev.D 97 (2018) 114025 [arXiv:1802.02995] [INSPIRE].

  8. [8]

    RBC, UKQCD collaboration, Calculation of the hadronic vacuum polarization contribution to the muon anomalous magnetic moment, Phys. Rev. Lett.121 (2018) 022003 [arXiv:1801.07224] [INSPIRE].

  9. [9]

    F. Campanario et al., Standard model radiative corrections in the pion form factor measurements do not explain the aμanomaly, Phys. Rev.D 100 (2019) 076004 [arXiv:1903.10197] [INSPIRE].

  10. [10]

    M. Davier, A. Hoecker, B. Malaescu and Z. Zhang, A new evaluation of the hadronic vacuum polarisation contributions to the muon anomalous magnetic moment and to \( \alpha \left({m}_Z^2\right) \), Eur. Phys. J.C 80 (2020) 241 [arXiv:1908.00921] [INSPIRE].

  11. [11]

    S. Borsányi et al., Leading-order hadronic vacuum polarization contribution to the muon magnetic momentfrom lattice QCD, arXiv:2002.12347 [INSPIRE].

  12. [12]

    M. Passera, W.J. Marciano and A. Sirlin, The muon g − 2 and the bounds on the Higgs boson mass, Phys. Rev.D 78 (2008) 013009 [arXiv:0804.1142] [INSPIRE].

  13. [13]

    A. Crivellin, M. Hoferichter, C.A. Manzari and M. Montull, Hadronic vacuum polarization: (g − 2)μ versus global electroweak fits, arXiv:2003.04886 [INSPIRE].

  14. [14]

    Muon g-2 collaboration, Muon (g − 2) technical design report, arXiv:1501.06858 [INSPIRE].

  15. [15]

    M. Lindner, M. Platscher and F.S. Queiroz, A call for new physics: the muon anomalous magnetic moment and lepton flavor violation, Phys. Rept.731 (2018) 1 [arXiv:1610.06587] [INSPIRE].

    ADS  MathSciNet  Article  Google Scholar 

  16. [16]

    T. Moroi, The muon anomalous magnetic dipole moment in the minimal supersymmetric standard model, Phys. Rev.D 53 (1996) 6565 [Erratum ibid.D 56 (1997) 4424] [hep-ph/9512396] [INSPIRE].

  17. [17]

    S.P. Martin and J.D. Wells, Muon anomalous magnetic dipole moment in supersymmetric theories, Phys. Rev.D 64 (2001) 035003 [hep-ph/0103067] [INSPIRE].

  18. [18]

    D. Stöckinger, The muon magnetic moment and supersymmetry, J. Phys.G 34 (2007) R45 [hep-ph/0609168] [INSPIRE].

  19. [19]

    M. Endo, K. Hamaguchi, S. Iwamoto and T. Yoshinaga, Muon g − 2 vs. LHC in supersymmetric models, JHEP01 (2014) 123 [arXiv:1303.4256] [INSPIRE].

  20. [20]

    M. Endo, K. Hamaguchi, S. Iwamoto and T. Kitahara, Muon g − 2 vs. LHC Run 2 in supersymmetric models, JHEP04 (2020) 165 [arXiv:2001.11025] [INSPIRE].

  21. [21]

    G.F. Giudice, P. Paradisi and M. Passera, Testing new physics with the electron g − 2, JHEP11 (2012) 113 [arXiv:1208.6583] [INSPIRE].

    ADS  Article  Google Scholar 

  22. [22]

    R.H. Parker et al., Measurement of the fine-structure constant as a test of the Standard Model, Science360 (2018) 191 [arXiv:1812.04130] [INSPIRE].

    ADS  MathSciNet  Article  Google Scholar 

  23. [23]

    H. Davoudiasl and W.J. Marciano, Tale of two anomalies, Phys. Rev.D 98 (2018) 075011 [arXiv:1806.10252] [INSPIRE].

  24. [24]

    A. Crivellin, M. Hoferichter and P. Schmidt-Wellenburg, Combined explanations of (g − 2)μ,eand implications for a large muon EDM, Phys. Rev.D 98 (2018) 113002 [arXiv:1807.11484] [INSPIRE].

  25. [25]

    J. Liu, C.E.M. Wagner and X.-P. Wang, A light complex scalar for the electron and muon anomalous magnetic moments, JHEP03 (2019) 008 [arXiv:1810.11028] [INSPIRE].

    ADS  Article  Google Scholar 

  26. [26]

    X.-F. Han, T. Li, L. Wang and Y. Zhang, Simple interpretations of lepton anomalies in the lepton-specific inert two-Higgs-doublet model, Phys. Rev.D 99 (2019) 095034 [arXiv:1812.02449] [INSPIRE].

  27. [27]

    M. Endo and W. Yin, Explaining electron and muon g − 2 anomaly in SUSY without lepton-flavor mixings, JHEP08 (2019) 122 [arXiv:1906.08768] [INSPIRE].

    ADS  Article  Google Scholar 

  28. [28]

    M. Abdullah, B. Dutta, S. Ghosh and T. Li, (g − 2)μ,eand the ANITA anomalous events in a three-loop neutrino mass model, Phys. Rev.D 100 (2019) 115006 [arXiv:1907.08109] [INSPIRE].

  29. [29]

    M. Bauer et al., Axion-like particles, lepton-flavor violation and a new explanation of aμand ae , Phys. Rev. Lett.124 (2020) 211803 [arXiv:1908.00008] [INSPIRE].

    ADS  Article  Google Scholar 

  30. [30]

    M. Badziak and K. Sakurai, Explanation of electron and muon g − 2 anomalies in the MSSM, JHEP10 (2019) 024 [arXiv:1908.03607] [INSPIRE].

    ADS  Article  Google Scholar 

  31. [31]

    A.E. Cárcamo Hernández, S.F. King, H. Lee and S.J. Rowley, Is it possible to explain the muon and electron g − 2 in a Zmodel?, arXiv:1910.10734 [INSPIRE].

  32. [32]

    G. Hiller, C. Hormigos-Feliu, D.F. Litim and T. Steudtner, Anomalous magnetic moments from asymptotic safety, arXiv:1910.14062 [INSPIRE].

  33. [33]

    C. Cornella, P. Paradisi and O. Sumensari, Hunting for ALPs with lepton flavor Violation, JHEP01 (2020) 158 [arXiv:1911.06279] [INSPIRE].

    ADS  Article  Google Scholar 

  34. [34]

    M. Endo, S. Iguro and T. Kitahara, Probing eμ flavor-violating ALP at Belle II, JHEP06 (2020) 040 [arXiv:2002.05948] [INSPIRE].

    Article  Google Scholar 

  35. [35]

    S. Jana, V.P. K. and S. Saad, Resolving electron and muon g − 2 within the 2HDM, arXiv:2003.03386 [INSPIRE].

  36. [36]

    L. Calibbi and G. Signorelli, Charged lepton flavour violation: an experimental and theoretical introduction, Riv. Nuovo Cim.41 (2018) 71 [arXiv:1709.00294] [INSPIRE].

    ADS  Google Scholar 

  37. [37]

    MEG collaboration, Search for the lepton flavour violating decay μ+ → e+γ with the full dataset of the MEG experiment, Eur. Phys. J.C 76 (2016) 434 [arXiv:1605.05081] [INSPIRE].

  38. [38]

    L. Calibbi, R. Ziegler and J. Zupan, Minimal models for dark matter and the muon g – 2 anomaly, JHEP07 (2018) 046 [arXiv:1804.00009] [INSPIRE].

    ADS  MathSciNet  Article  Google Scholar 

  39. [39]

    C.D. Froggatt and H.B. Nielsen, Hierarchy of quark masses, Cabibbo angles and CP-violation, Nucl. Phys.B 147 (1979) 277 [INSPIRE].

    ADS  Article  Google Scholar 

  40. [40]

    M. Leurer, Y. Nir and N. Seiberg, Mass matrix models, Nucl. Phys.B 398 (1993) 319 [hep-ph/9212278] [INSPIRE].

  41. [41]

    M. Leurer, Y. Nir and N. Seiberg, Mass matrix models: the sequel, Nucl. Phys.B 420 (1994) 468 [hep-ph/9310320] [INSPIRE].

  42. [42]

    N. Haba, Y. Shimizu and T. Yamada, Muon and electron g − 2 and the origin of fermion mass hierarchy, arXiv:2002.10230 [INSPIRE].

  43. [43]

    A. Czarnecki and W.J. Marciano, The muon anomalous magnetic moment: a harbinger for ‘new physics’, Phys. Rev.D 64 (2001) 013014 [hep-ph/0102122] [INSPIRE].

  44. [44]

    H. Okada and K. Yagyu, Radiative generation of lepton masses, Phys. Rev.D 89 (2014) 053008 [arXiv:1311.4360] [INSPIRE].

  45. [45]

    M. Bauer and M. Neubert, Minimal Leptoquark Explanation for the \( {R}_{D^{\left(\ast \right)}} \), RKand (g − 2)gAnomalies, Phys. Rev. Lett.116 (2016) 141802 [arXiv:1511.01900] [INSPIRE].

  46. [46]

    E. Coluccio Leskow, G. D’Ambrosio, A. Crivellin and D. Müller, (g − 2)μ, lepton flavor violation and Z decays with leptoquarks: Correlations and future prospects, Phys. Rev.D 95 (2017) 055018 [arXiv:1612.06858] [INSPIRE].

  47. [47]

    A. Crivellin, D. Müller, A. Signer and Y. Ulrich, Correlating lepton flavor universality violation in B decays with μ → eγ using leptoquarks, Phys. Rev.D 97 (2018) 015019 [arXiv:1706.08511] [INSPIRE].

  48. [48]

    I. Doršner, S. Fajfer and O. Sumensari, Muon g − 2 and scalar leptoquark mixing, arXiv:1910.03877 [INSPIRE].

  49. [49]

    L. Calibbi, T. Li, Y. Li and B. Zhu, Simple model for large CP-violation in charm decays, B-physics anomalies, muon g − 2 and Dark Matter, arXiv:1912.02676 [INSPIRE].

  50. [50]

    A. Crivellin, D. Müller and F. Saturnino, Flavor phenomenology of the leptoquark singlet-triplet model, JHEP06 (2020) 020 [arXiv:1912.04224] [INSPIRE].

  51. [51]

    W. Altmannshofer et al., Electric dipole moments in a leptoquark scenario for the B-physics anomalies, JHEP05 (2020) 069 [arXiv:2002.01400] [INSPIRE].

    ADS  Article  Google Scholar 

  52. [52]

    I. Bigaran and R.R. Volkas, Getting chirality right: top-philic scalar leptoquark solution to the (g − 2)e,μpuzzle, arXiv:2002.12544 [INSPIRE].

  53. [53]

    L. Calibbi, Z. Lalak, S. Pokorski and R. Ziegler, The messenger sector of SUSY flavour models and radiative breaking of flavour universality, JHEP06 (2012) 018 [arXiv:1203.1489] [INSPIRE].

    ADS  Article  Google Scholar 

  54. [54]

    L. Calibbi, Z. Lalak, S. Pokorski and R. Ziegler, Universal constraints on low-energy flavour models, JHEP07 (2012) 004 [arXiv:1204.1275] [INSPIRE].

    ADS  Article  Google Scholar 

  55. [55]

    D. Das, M.L. López-Ibáñez, M.J. Pérez and O. Vives, Effective theories of flavor and the nonuniversal MSSM, Phys. Rev.D 95 (2017) 035001 [arXiv:1607.06827] [INSPIRE].

  56. [56]

    M.L. López-Ibáñez, A. Melis, M.J. Pérez and O. Vives, Slepton non-universality in the flavor-effective MSSM, JHEP11 (2017) 162 [Erratum ibid.04 (2018) 015] [arXiv:1710.02593] [INSPIRE].

  57. [57]

    Particle Data Group collaboration, Review of particle physics, Phys. Rev.D 98 (2018) 030001 [INSPIRE].

  58. [58]

    ALEPH, DELPHI, L3, OPAL, LEP Electroweak collaboration, Electroweak measurements in electron-positron collisions at W-boson-pair energies at LEP, Phys. Rept.532 (2013) 119 [arXiv:1302.3415] [INSPIRE].

  59. [59]

    R.K. Ellis et al., Physics briefing book, arXiv:1910.11775 [INSPIRE].

  60. [60]

    N. Kumar and S.P. Martin, Vectorlike leptons at the Large Hadron Collider, Phys. Rev.D 92 (2015) 115018 [arXiv:1510.03456] [INSPIRE].

    ADS  Google Scholar 

  61. [61]

    ATLAS collaboration, Search for heavy lepton resonances decaying to a Z boson and a lepton in pp collisions at \( \sqrt{s} \) = 8 TeV with the ATLAS detector, JHEP09 (2015) 108 [arXiv:1506.01291] [INSPIRE].

  62. [62]

    ATLAS collaboration, Search for supersymmetry in events with four or more leptons in \( \sqrt{s} \) = 13 TeV pp collisions with ATLAS, Phys. Rev.D 98 (2018) 032009 [arXiv:1804.03602] [INSPIRE].

  63. [63]

    CMS collaboration, Search for vector-like leptons in multilepton final states in proton-proton collisions at \( \sqrt{s} \) = 13 TeV, Phys. Rev.D 100 (2019) 052003 [arXiv:1905.10853] [INSPIRE].

  64. [64]

    CMS collaboration, Search for physics beyond the standard model in multilepton final states in proton-proton collisions at \( \sqrt{s} \) = 13 TeV, JHEP03 (2020) 051 [arXiv:1911.04968] [INSPIRE].

  65. [65]

    ACME collaboration, Improved limit on the electric dipole moment of the electron, Nature562 (2018) 355.

Download references

Open Access

This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited

Author information



Corresponding author

Correspondence to Aurora Melis.

Additional information

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

ArXiv ePrint: 2003.06633

Rights and permissions

This article is published under an open access license. Please check the 'Copyright Information' section for details of this license and what re-use is permitted. If your intended use exceeds what is permitted by the license or if you are unable to locate the licence and re-use information, please contact the Rights and Permissions team.

About this article

Verify currency and authenticity via CrossMark

Cite this article

Calibbi, L., López-Ibáñez, M.L., Melis, A. et al. Muon and electron g − 2 and lepton masses in flavor models. J. High Energ. Phys. 2020, 87 (2020).

Download citation


  • Precision QED
  • Beyond Standard Model
  • Effective Field Theories
  • Quark Masses and SM Parameters