Abstract
We consider scenarios with a heavy Z′ gauge boson with flavour non-universal quark and lepton couplings with the goal to illustrate how the cancellation of gauge anomalies generated by the presence of an additional U(1)′ gauge symmetry would imply correlations between FCNC processes within the quark sector, within the lepton sector and most interestingly between quark flavour and lepton flavour violating processes. To this end we present simple scenarios with only left-handed flavour-violating Z′ couplings and those in which also right-handed flavour-violating couplings are present. The considered scenarios are characterized by a small number of free parameters but in contrast to gauge anomaly cancellation in the Standard Model, in which it takes place separately within each generation, in our scenarios anomaly cancellation involves simultaneously quarks and leptons of all three generations. Our models involve, beyond the ordinary quarks and leptons, three heavy right-handed neutrinos. The models with only left-handed FCNCs of Z′ involve beyond \( {g}_{Z^{\prime }} \) and \( {M}_{Z^{\prime }} \) two real parameters characterizing the charges of all fermions under the U(1)′ gauge symmetry and the CKM and PMNS ones in the quark and lepton sectors, respectively. The models with the right-handed FCNCs of Z′ involve few additional parameters. Imposing constraints from well measured ∆F = 2 observables we identify a number of interesting correlations that involve e.g. ε′/ε, Bs,d → μ+μ−, B → K(K*)ℓ+ℓ−, \( {K}^{+}\to {\pi}^{+}\nu \overline{\nu},{K}_L\to {\pi}^0\nu \overline{\nu} \) and purely lepton flavour violating decays like μ → eγ, μ → 3e, τ → 3μ and μ − e conversion among others. Also (g − 2)μ,e are considered. The impact of the experimental μ → eγ, μ → 3e and in particular μ − e conversion bounds on rare K and B decays is emphasized.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
P. Langacker, The physics of heavy z′ gauge bosons, Rev. Mod. Phys. 81 (2009) 1199 [arXiv:0801.1345] [INSPIRE].
J. Erler, P. Langacker, S. Munir and E. Rojas, Improved constraints on Z′ bosons from electroweak precision data, JHEP 08 (2009) 017 [arXiv:0906.2435] [INSPIRE].
A.J. Buras, F. De Fazio and J. Girrbach, The anatomy of Z′ and Z with flavour changing neutral currents in the flavour precision era, JHEP 02 (2013) 116 [arXiv:1211.1896] [INSPIRE].
P. Langacker and M. Plümacher, Flavor changing effects in theories with a heavy Z′ boson with family nonuniversal couplings, Phys. Rev. D 62 (2000) 013006 [hep-ph/0001204] [INSPIRE].
V. Barger, C.-W. Chiang, P. Langacker and H.-S. Lee, Z′ mediated flavor changing neutral currents in B meson decays, Phys. Lett. B 580 (2004) 186 [hep-ph/0310073] [INSPIRE].
V. Barger, C.-W. Chiang, J. Jiang and P. Langacker, \( {B}_s-{\overline{B}}_s \) mixing in Z′ models with flavor-changing neutral currents, Phys. Lett. B 596 (2004) 229 [hep-ph/0405108] [INSPIRE].
V. Barger et al., b → s transitions in family-dependent U(1)′ models, JHEP 12 (2009) 048 [arXiv:0906.3745] [INSPIRE].
V. Barger et al., Family non-universal U(1)′ gauge symmetries and b → s transitions, Phys. Rev. D 80 (2009) 055008 [arXiv:0902.4507] [INSPIRE].
A. Celis, J. Fuentes-Martin, M. Jung and H. Serodio, Family nonuniversal Z′ models with protected flavor-changing interactions, Phys. Rev. D 92 (2015) 015007 [arXiv:1505.03079] [INSPIRE].
W. Altmannshofer, S. Gori, M. Pospelov and I. Yavin, Quark flavor transitions in Lμ-Lτ models, Phys. Rev. D 89 (2014) 095033 [arXiv:1403.1269] [INSPIRE].
A. Crivellin et al., Lepton-flavour violating B decays in generic Z′ models, Phys. Rev. D 92 (2015) 054013 [arXiv:1504.07928] [INSPIRE].
A. Crivellin, G. D’Ambrosio and J. Heeck, Addressing the LHC flavor anomalies with horizontal gauge symmetries, Phys. Rev. D 91 (2015) 075006 [arXiv:1503.03477] [INSPIRE].
W. Altmannshofer, M. Carena and A. Crivellin, Lμ-Lτ theory of Higgs flavor violation and (g − 2)μ, Phys. Rev. D 94 (2016) 095026 [arXiv:1604.08221] [INSPIRE].
L. Calibbi et al., Z′ models with less-minimal flavour violation, arXiv:1910.00014 [INSPIRE].
B.C. Allanach and J. Davighi, Third family hypercharge model for \( {R}_{K^{\left(\ast \right)}} \) and aspects of the fermion mass problem, JHEP 12 (2018) 075 [arXiv:1809.01158] [INSPIRE].
W. Altmannshofer, J. Davighi and M. Nardecchia, Gauging the accidental symmetries of the standard model and implications for the flavor anomalies, Phys. Rev. D 101 (2020) 015004 [arXiv:1909.02021] [INSPIRE].
M. Carena, A. Daleo, B.A. Dobrescu and T.M.P. Tait, Z′ gauge bosons at the Tevatron, Phys. Rev. D 70 (2004) 093009 [hep-ph/0408098] [INSPIRE].
J. Ellis, M. Fairbairn and P. Tunney, Anomaly-free dark matter models are not so simple, JHEP 08 (2017) 053 [arXiv:1704.03850] [INSPIRE].
G. D’Amico et al., Flavour anomalies after the \( {R}_{K^{\ast }} \) measurement, JHEP 09 (2017) 010 [arXiv:1704.05438] [INSPIRE].
R. Alonso, P. Cox, C. Han and T.T. Yanagida, Anomaly-free local horizontal symmetry and anomaly-full rare B-decays, Phys. Rev. D 96 (2017) 071701 [arXiv:1704.08158] [INSPIRE].
B. Allanach, F.S. Queiroz, A. Strumia and S. Sun, Z′ models for the LHCb and g − 2 muon anomalies, Phys. Rev. D 93 (2016) 055045 [Erratum ibid. D 95 (2017) 119902] [arXiv:1511.07447] [INSPIRE].
F. Kahlhoefer, K. Schmidt-Hoberg, T. Schwetz and S. Vogl, Implications of unitarity and gauge invariance for simplified dark matter models, JHEP 02 (2016) 016 [arXiv:1510.02110] [INSPIRE].
A. Ekstedt et al., Constraining minimal anomaly free U(1) extensions of the Standard Model, JHEP 11 (2016) 071 [arXiv:1605.04855] [INSPIRE].
A. Ismail, W.-Y. Keung, K.-H. Tsao and J. Unwin, Axial vector Z′ and anomaly cancellation, Nucl. Phys. B 918 (2017) 220 [arXiv:1609.02188] [INSPIRE].
P.J. Fox, J. Liu, D. Tucker-Smith and N. Weiner, An effective Z′ , Phys. Rev. D 84 (2011) 115006 [arXiv:1104.4127] [INSPIRE].
B.C. Allanach, J. Davighi and S. Melville, An anomaly-free ATLAS: charting the space of flavour-dependent gauged U(1) extensions of the standard model, JHEP 02 (2019) 082 [arXiv:1812.04602] [INSPIRE].
B.C. Allanach, B. Gripaios and J. Tooby-Smith, Solving local anomaly equations in gauge-rank extensions of the standard model, arXiv:1912.10022 [INSPIRE].
D.B. Costa, B.A. Dobrescu and P.J. Fox, General solution to the U(1) anomaly equations, Phys. Rev. Lett. 123 (2019) 151601 [arXiv:1905.13729] [INSPIRE].
J. Aebischer, C. Bobeth and A.J. Buras, On the importance of NNLO QCD and isospin-breaking corrections in ε′/ε, Eur. Phys. J. C 80 (2020) 1 [arXiv:1909.05610] [INSPIRE].
F. Feruglio, P. Paradisi and A. Pattori, On the importance of electroweak corrections for B anomalies, JHEP 09 (2017) 061 [arXiv:1705.00929] [INSPIRE].
D. Buttazzo, A. Greljo, G. Isidori and D. Marzocca, B-physics anomalies: a guide to combined explanations, JHEP 11 (2017) 044 [arXiv:1706.07808] [INSPIRE].
J. Aebischer, J. Kumar, P. Stangl and D.M. Straub, A global likelihood for precision constraints and flavour anomalies, Eur. Phys. J. C 79 (2019) 509 [arXiv:1810.07698] [INSPIRE].
J. Aebischer et al., B-decay discrepancies after Moriond 2019, arXiv:1903.10434 [INSPIRE].
N. Cabibbo, Unitary symmetry and leptonic decays, Phys. Rev. Lett. 10 (1963) 531 [INSPIRE].
M. Kobayashi and T. Maskawa, CP violation in the renormalizable theory of weak interaction, Prog. Theor. Phys. 49 (1973) 652 [INSPIRE].
B. Pontecorvo, Mesonium and anti-mesonium, Sov. Phys. JETP 6 (1957) 429 [INSPIRE].
Z. Maki, M. Nakagawa and S. Sakata, Remarks on the unified model of elementary particles, Prog. Theor. Phys. 28 (1962) 870 [INSPIRE].
J. Aebischer et al., WCxf: an exchange format for Wilson coefficients beyond the standard model, Comput. Phys. Commun. 232 (2018) 71 [arXiv:1712.05298] [INSPIRE].
J. Aebischer, A. Crivellin, M. Fael and C. Greub, Matching of gauge invariant dimension-six operators for b → s and b → c transitions, JHEP 05 (2016) 037 [arXiv:1512.02830] [INSPIRE].
A.J. Buras, K. Gemmler and G. Isidori, Quark flavour mixing with right-handed currents: an effective theory approach, Nucl. Phys. B 843 (2011) 107 [arXiv:1007.1993] [INSPIRE].
M. Blanke, A.J. Buras, K. Gemmler and T. Heidsieck, ∆F = 2 observables and B → Xqγ decays in the left-right model: Higgs particles striking back, JHEP 03 (2012) 024 [arXiv:1111.5014] [INSPIRE].
I. Esteban et al., Global analysis of three-flavour neutrino oscillations: synergies and tensions in the determination of θ23, δCP and the mass ordering, JHEP 01 (2019) 106 [arXiv:1811.05487] [INSPIRE].
A.J. Buras, F. De Fazio, J. Girrbach and M.V. Carlucci, The anatomy of quark flavour observables in 331 models in the flavour precision era, JHEP 02 (2013) 023 [arXiv:1211.1237] [INSPIRE].
A.J. Buras, New physics patterns in ε′/ε and εK with implications for rare kaon decays and ∆MK, JHEP 04 (2016) 071 [arXiv:1601.00005] [INSPIRE].
J. Aebischer, C. Bobeth, A.J. Buras and D.M. Straub, Anatomy of ε′/ε beyond the standard model, Eur. Phys. J. C 79 (2019) 219 [arXiv:1808.00466] [INSPIRE].
J. Aebischer et al., Master formula for ε′/ε beyond the standard model, Phys. Lett. B 792 (2019) 465 [arXiv:1807.02520] [INSPIRE].
J. Aebischer, A.J. Buras and J.-M. Gérard, BSM hadronic matrix elements for ϵ′/ϵ and K → ππ decays in the Dual QCD approach, JHEP 02 (2019) 021 [arXiv:1807.01709] [INSPIRE].
J. Aebischer, M. Fael, C. Greub and J. Virto, B physics beyond the standard model at one loop: complete renormalization group evolution below the electroweak scale, JHEP 09 (2017) 158 [arXiv:1704.06639] [INSPIRE].
E.E. Jenkins, A.V. Manohar and P. Stoffer, Low-energy effective field theory below the electroweak scale: anomalous dimensions, JHEP 01 (2018) 084 [arXiv:1711.05270] [INSPIRE].
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].
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].
BaBar collaboration, Searches for lepton flavor violation in the decays τ± → e±γ and τ± → μ±γ, Phys. Rev. Lett. 104 (2010) 021802 [arXiv:0908.2381] [INSPIRE].
D.M. Straub, flavio: a Python package for flavour and precision phenomenology in the standard model and beyond, arXiv:1810.08132 [INSPIRE].
A. Brignole and A. Rossi, Anatomy and phenomenology of μ-τ lepton flavor violation in the MSSM, Nucl. Phys. B 701 (2004) 3 [hep-ph/0404211] [INSPIRE].
A. Crivellin, S. Najjari and J. Rosiek, Lepton flavor violation in the standard model with general dimension-six operators, JHEP 04 (2014) 167 [arXiv:1312.0634] [INSPIRE].
HFLAV collaboration, Averages of b-hadron, c-hadron and τ-lepton properties as of 2018, arXiv:1909.12524 [INSPIRE].
Particle Data Group collaboration, Review of particle physics, Phys. Rev. D 98 (2018) 030001.
J. Hisano, T. Moroi, K. Tobe and M. Yamaguchi, Lepton flavor violation via right-handed neutrino Yukawa couplings in supersymmetric standard model, Phys. Rev. D 53 (1996) 2442 [hep-ph/9510309] [INSPIRE].
J. Bernabeu, E. Nardi and D. Tommasini, μ-e conversion in nuclei and Z′ physics, Nucl. Phys. B 409 (1993) 69 [hep-ph/9306251] [INSPIRE].
T. Suzuki, D.F. Measday and J.P. Roalsvig, Total nuclear capture rates for negative muons, Phys. Rev. C 35 (1987) 2212.
SINDRUM II collaboration, A search for muon to electron conversion in muonic gold, Eur. Phys. J. C 47 (2006) 337 [INSPIRE].
G. Isidori and R. Unterdorfer, On the short distance constraints from KL,S → μ+μ−, JHEP 01 (2004) 009 [hep-ph/0311084] [INSPIRE].
CMS collaboration, Measurement of the \( {B}_s^0 \) → μ+μ− Branching Fraction and Search for B0 → μ+μ− with the CMS Experiment, Phys. Rev. Lett. 111 (2013) 101804 [arXiv:1307.5025] [INSPIRE].
CMS, LHCb collaboration, Observation of the rare \( {B}_s^0 \) → μ+μ− decay from the combined analysis of CMS and LHCb data, Nature 522 (2015) 68 [arXiv:1411.4413] [INSPIRE].
LHCb collaboration, Measurement of the \( {B}_s^0 \) → μ+μ− branching fraction and effective lifetime and search for B0 → μ+μ− decays, Phys. Rev. Lett. 118 (2017) 191801 [arXiv:1703.05747] [INSPIRE].
ATLAS collaboration, Study of the rare decays of \( {B}_s^0 \) and B0 mesons into muon pairs using data collected during 2015 and 2016 with the ATLAS detector, JHEP 04 (2019) 098 [arXiv:1812.03017] [INSPIRE].
A.J. Buras, F. De Fazio and J. Girrbach, ∆I = 1/2 rule, ε′/ε and K → \( \pi \nu \overline{\nu} \) in Z′(Z ) and G′ models with FCNC quark couplings, Eur. Phys. J. C 74 (2014) 2950 [arXiv:1404.3824] [INSPIRE].
A.J. Buras, D. Buttazzo, J. Girrbach-Noe and R. Knegjens, Can we reach the Zeptouniverse with rare K and Bs,d decays?, JHEP 11 (2014) 121 [arXiv:1408.0728] [INSPIRE].
M. Blanke, Insights from the interplay of K → \( \pi \nu \overline{\nu} \) and ϵK on the new physics flavour structure, Acta Phys. Polon. B 41 (2010) 127 [arXiv:0904.2528] [INSPIRE].
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
Authors and Affiliations
Corresponding author
Additional information
ArXiv ePrint: 1912.09308
Rights and permissions
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.
About this article
Cite this article
Aebischer, J., Buras, A.J., Cerdà-Sevilla, M. et al. Quark-lepton connections in Z′ mediated FCNC processes: gauge anomaly cancellations at work. J. High Energ. Phys. 2020, 183 (2020). https://doi.org/10.1007/JHEP02(2020)183
Received:
Revised:
Accepted:
Published:
DOI: https://doi.org/10.1007/JHEP02(2020)183