Abstract
We fit the available data on exclusive semileptonic b → uℓ−\( \overline{\nu} \) decays within the Standard Model and in the Weak Effective Theory. Assuming Standard Model dynamics, we find \( \left|{V}_{ub}\right|={3.59}_{-0.12}^{+0.13}\times {10}^{-3} \). Lifting this assumption, we obtain stringent constraints on the coefficients of the ubℓν sector of the Weak Effective Theory. Performing a Bayesian model comparison, we find that a beyond the Standard Model interpretation is favoured over a Standard Model interpretation of the available data. We provide a Gaussian mixture model that enables the efficient use of our fit results in subsequent analyses beyond the Standard Model, within and beyond the framework of the Standard Model Effective Field Theory.
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References
Particle Data Group collaboration, Review of particle physics, PTEP 2022 (2022) 083C01 [INSPIRE].
D. Leljak, B. Melić and D. van Dyk, The \( \overline{B} \) → π form factors from QCD and their impact on |Vub|, JHEP 07 (2021) 036 [arXiv:2102.07233] [INSPIRE].
Belle collaboration, Measurements of partial branching fractions of inclusive B → Xuℓ+νℓ decays with hadronic tagging, Phys. Rev. D 104 (2021) 012008 [arXiv:2102.00020] [INSPIRE].
F.U. Bernlochner, Z. Ligeti and S. Turczyk, New ways to search for right-handed current in B → \( \rho \ell \overline{\nu} \) decay, Phys. Rev. D 90 (2014) 094003 [arXiv:1408.2516] [INSPIRE].
T. Enomoto and M. Tanaka, Right-handed current with CP violation in the b → u transition, Phys. Rev. D 91 (2015) 014033 [arXiv:1411.1177] [INSPIRE].
S. Sahoo, A. Ray and R. Mohanta, Model independent investigation of rare semileptonic b → \( ul\overline{\nu} \)l decay processes, Phys. Rev. D 96 (2017) 115017 [arXiv:1711.10924] [INSPIRE].
G. Banelli, R. Fleischer, R. Jaarsma and G. Tetlalmatzi-Xolocotzi, Decoding (pseudo)-scalar operators in leptonic and semileptonic B decays, Eur. Phys. J. C 78 (2018) 911 [arXiv:1809.09051] [INSPIRE].
P. Colangelo, F. De Fazio and F. Loparco, Probing new physics with \( \overline{B} \) → ρ(770)ℓ−\( \overline{\nu} \)ℓ and \( \overline{B} \) → a1(1260)ℓ−\( \overline{\nu} \)ℓ, Phys. Rev. D 100 (2019) 075037 [arXiv:1906.07068] [INSPIRE].
R. Fleischer, R. Jaarsma and G. Tetlalmatzi-Xolocotzi, Mapping out the space for new physics with leptonic and semileptonic B(c) decays, Eur. Phys. J. C 81 (2021) 658 [arXiv:2104.04023] [INSPIRE].
A. Biswas, S. Nandi and I. Ray, Extractions of |Vub|/|Vcb| from a combined study of the exclusive b → u(c)ℓ−\( \overline{\nu} \)ℓ decays, JHEP 07 (2023) 024 [arXiv:2212.02528] [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: operators and matching, JHEP 03 (2018) 016 [arXiv:1709.04486] [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].
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].
C. Bobeth et al., Lepton-flavour non-universality of \( \overline{B} \) → D*ℓ\( \overline{\nu} \) angular distributions in and beyond the Standard Model, Eur. Phys. J. C 81 (2021) 984 [arXiv:2104.02094] [INSPIRE].
W. Buchmuller and D. Wyler, Effective Lagrangian analysis of new interactions and flavor conservation, Nucl. Phys. B 268 (1986) 621 [INSPIRE].
B. Grzadkowski, M. Iskrzynski, M. Misiak and J. Rosiek, Dimension-six terms in the Standard Model Lagrangian, JHEP 10 (2010) 085 [arXiv:1008.4884] [INSPIRE].
H. Jeffreys, The theory of probability, Oxford University Press (1939) [INSPIRE].
HFLAV collaboration, Averages of b-hadron, c-hadron, and τ-lepton properties as of 2018, Eur. Phys. J. C 81 (2021) 226 [arXiv:1909.12524] [INSPIRE].
BaBar collaboration, Study of B → πℓν and B → ρℓν decays and determination of |Vub|, Phys. Rev. D 83 (2011) 032007 [arXiv:1005.3288] [INSPIRE].
BaBar collaboration, Branching fraction and form-factor shape measurements of exclusive charmless semileptonic B decays, and determination of |Vub|, Phys. Rev. D 86 (2012) 092004 [arXiv:1208.1253] [INSPIRE].
Belle collaboration, Measurement of the decay B0 → π−ℓ+ν and determination of |Vub|, Phys. Rev. D 83 (2011) 071101 [arXiv:1012.0090] [INSPIRE].
Belle collaboration, Study of exclusive B → Xuℓν decays and extraction of ||Vub|| using full reconstruction tagging at the Belle experiment, Phys. Rev. D 88 (2013) 032005 [arXiv:1306.2781] [INSPIRE].
F.U. Bernlochner, M.T. Prim and D.J. Robinson, B → ρℓ\( \overline{\nu} \) and ωℓ\( \overline{\nu} \) in and beyond the Standard Model: improved predictions and Vub , Phys. Rev. D 104 (2021) 034032 [arXiv:2104.05739] [INSPIRE].
S. Faller et al., Disentangling the decay observables in B− → π+π−ℓ−\( \overline{\nu} \)ℓ, Phys. Rev. D 89 (2014) 014015 [arXiv:1310.6660] [INSPIRE].
X.-W. Kang, B. Kubis, C. Hanhart and U.-G. Meißner, Bl4 decays and the extraction of |Vub|, Phys. Rev. D 89 (2014) 053015 [arXiv:1312.1193] [INSPIRE].
C. Hambrock, A. Khodjamirian and A. Rusov, Hadronic effects and observables in B → πℓ+ℓ− decay at large recoil, Phys. Rev. D 92 (2015) 074020 [arXiv:1506.07760] [INSPIRE].
C. Hambrock and A. Khodjamirian, Form factors in \( \overline{B} \)0 → ππℓ\( \overline{\nu} \)ℓ from QCD light-cone sum rules, Nucl. Phys. B 905 (2016) 373 [arXiv:1511.02509] [INSPIRE].
P. Böer, T. Feldmann and D. van Dyk, QCD factorization theorem for B → ππℓν decays at large dipion masses, JHEP 02 (2017) 133 [arXiv:1608.07127] [INSPIRE].
S. Cheng, A. Khodjamirian and J. Virto, B → ππ form factors from light-cone sum rules with B-meson distribution amplitudes, JHEP 05 (2017) 157 [arXiv:1701.01633] [INSPIRE].
S. Cheng, A. Khodjamirian and J. Virto, Timelike-helicity B → ππ form factor from light-cone sum rules with dipion distribution amplitudes, Phys. Rev. D 96 (2017) 051901 [arXiv:1709.00173] [INSPIRE].
T. Feldmann, D. Van Dyk and K.K. Vos, Revisiting B → ππℓν at large dipion masses, JHEP 10 (2018) 030 [arXiv:1807.01924] [INSPIRE].
L. Leskovec et al., A lattice QCD study of the B → ππℓ\( \overline{\nu} \) transition, PoS LATTICE2022 (2023) 416 [arXiv:2212.08833] [INSPIRE].
Belle collaboration, Measurement of the branching fraction of the decay B+ → π+π−ℓ+νℓ in fully reconstructed events at Belle, Phys. Rev. D 103 (2021) 112001 [arXiv:2005.07766] [INSPIRE].
BaBar collaboration, Branching fraction measurement of B+ → ωℓ+ν decays, Phys. Rev. D 87 (2013) 032004 [Erratum ibid. 87 (2013) 099904] [arXiv:1205.6245] [INSPIRE].
A. Bharucha, D.M. Straub and R. Zwicky, B → Vℓ+ℓ− in the Standard Model from light-cone sum rules, JHEP 08 (2016) 098 [arXiv:1503.05534] [INSPIRE].
ROOT collaboration, HistFactory: a tool for creating statistical models for use with RooFit and RooStats, CERN-OPEN-2012-016, CERN, Geneva, Switzerland (2012).
Belle collaboration, Search for B+ → μ+νμ and B+ → μ+ N with inclusive tagging, Phys. Rev. D 101 (2020) 032007 [arXiv:1911.03186] [INSPIRE].
Belle collaboration, Measurement of the decays B → ηℓνℓ and B → η′ℓνℓ in fully reconstructed events at Belle, Phys. Rev. D 96 (2017) 091102 [arXiv:1703.10216] [INSPIRE].
G. Duplancic and B. Melic, Form factors of B, Bs → η(′) and D, Ds → η(′) transitions from QCD light-cone sum rules, JHEP 11 (2015) 138 [arXiv:1508.05287] [INSPIRE].
Belle collaboration, Measurement of the branching fractions of the B+ → ηℓ+νℓ and B+ → η′ℓ+νℓ decays with signal-side only reconstruction in the full q2 range, Phys. Rev. D 106 (2022) 032013 [arXiv:2104.13354] [INSPIRE].
Belle collaboration, Measurement of |Vub| using inclusive B → Xuℓnu decays with a novel Xu reconstruction method, Phys. Rev. Lett. 92 (2004) 101801 [hep-ex/0311048] [INSPIRE].
Belle collaboration, Measurement of inclusive charmless semileptonic B-meson decays at the endpoint of the electron momentum spectrum, Phys. Lett. B 621 (2005) 28 [hep-ex/0504046] [INSPIRE].
BaBar collaboration, Determination of |Vub| from measurements of the electron and neutrino momenta in inclusive semileptonic B decays, Phys. Rev. Lett. 95 (2005) 111801 [Erratum ibid. 97 (2006) 019903] [hep-ex/0506036] [INSPIRE].
BaBar collaboration, Measurement of the inclusive electron spectrum in charmless semileptonic B decays near the kinematic endpoint and determination of |Vub|, Phys. Rev. D 73 (2006) 012006 [hep-ex/0509040] [INSPIRE].
BaBar collaboration, Study of \( \overline{B} \) → Xuℓ\( \overline{\nu} \) decays in \( B\overline{B} \) events tagged by a fully reconstructed B-meson decay and determination of |Vub|, Phys. Rev. D 86 (2012) 032004 [arXiv:1112.0702] [INSPIRE].
BaBar collaboration, Measurement of the inclusive electron spectrum from B meson decays and determination of |Vub|, Phys. Rev. D 95 (2017) 072001 [arXiv:1611.05624] [INSPIRE].
LHCb collaboration, Determination of the quark coupling strength |Vub| using baryonic decays, Nature Phys. 11 (2015) 743 [arXiv:1504.01568] [INSPIRE].
LHCb collaboration, First observation of the decay \( {B}_s^0 \) → K−μ+νμ and measurement of |Vub|/|Vcb|, Phys. Rev. Lett. 126 (2021) 081804 [arXiv:2012.05143] [INSPIRE].
T. Feldmann, B. Müller and D. van Dyk, Analyzing b → u transitions in semileptonic \( \overline{B} \)s → K*+(→ Kπ)ℓ−\( \overline{\nu} \)ℓ decays, Phys. Rev. D 92 (2015) 034013 [arXiv:1503.09063] [INSPIRE].
CKMfitter Group collaboration, CP violation and the CKM matrix: assessing the impact of the asymmetric B factories, Eur. Phys. J. C 41 (2005) 1 [hep-ph/0406184] [INSPIRE].
C. Bourrely, I. Caprini and L. Lellouch, Model-independent description of B → πℓν decays and a determination of |Vub|, Phys. Rev. D 79 (2009) 013008 [Erratum ibid. 82 (2010) 099902] [arXiv:0807.2722] [INSPIRE].
Fermilab Lattice and MILC collaborations, |Vub| from B → πℓν decays and (2 + 1)-flavor lattice QCD, Phys. Rev. D 92 (2015) 014024 [arXiv:1503.07839] [INSPIRE].
Fermilab Lattice and MILC collaborations, B → πℓℓ form factors for new-physics searches from lattice QCD, Phys. Rev. Lett. 115 (2015) 152002 [arXiv:1507.01618] [INSPIRE].
J.M. Flynn et al., B → πℓν and Bs → Kℓν form factors and |Vub| from 2 + 1-flavor lattice QCD with domain-wall light quarks and relativistic heavy quarks, Phys. Rev. D 91 (2015) 074510 [arXiv:1501.05373] [INSPIRE].
N. Gubernari, A. Kokulu and D. van Dyk, B → P and B → V form factors from B-meson light-cone sum rules beyond leading twist, JHEP 01 (2019) 150 [arXiv:1811.00983] [INSPIRE].
D. Leljak et al., EOS/DATA-2023-01: supplementary material for EOS/ANALYSIS-2022-05, Zenodo, June 2023.
EOS Authors collaboration, EOS: a software for flavor physics phenomenology, Eur. Phys. J. C 82 (2022) 569 [arXiv:2111.15428] [INSPIRE].
M. Duraisamy, P. Sharma and A. Datta, Azimuthal B → D*τ−\( \overline{\nu} \)τ angular distribution with tensor operators, Phys. Rev. D 90 (2014) 074013 [arXiv:1405.3719] [INSPIRE].
E. Higson, W. Handley, M. Hobson and A. Lasenby, Dynamic nested sampling: an improved algorithm for parameter estimation and evidence calculation, Stat. Comput. 29 (2018) 891.
J.S. Speagle, dynesty: a dynamic nested sampling package for estimating Bayesian posteriors and evidences, Mon. Not. Roy. Astron. Soc. 493 (2020) 3132 [arXiv:1904.02180] [INSPIRE].
S. Koposov et al., joshspeagle/dynesty: v2.0.3, Zenodo, December 2022.
D. Van Dyk et al., eos/eos: EOS version 1.0.8, Zenodo, June 2023.
G. Martinelli, S. Simula and L. Vittorio, Exclusive semileptonic B → πℓνℓ and Bs → Kℓνℓ decays through unitarity and lattice QCD, JHEP 08 (2022) 022 [arXiv:2202.10285] [INSPIRE].
A. Bazavov et al., B- and D-meson leptonic decay constants from four-flavor lattice QCD, Phys. Rev. D 98 (2018) 074512 [arXiv:1712.09262] [INSPIRE].
F. Pedregosa et al., Scikit-learn: machine learning in python, J. Machine Learning Res. 12 (2011) 2825 [arXiv:1201.0490] [INSPIRE].
M. Kilbinger et al., Bayesian model comparison in cosmology with population Monte Carlo, Mon. Not. Roy. Astron. Soc. 405 (2010) 2381 [arXiv:0912.1614] [INSPIRE].
F. Beaujean, S. Jahn and D. Straub, fredRos/pypmc: support python 3.7 and wheels, Zenodo, June 2019.
J. Aebischer, J. Kumar and D.M. Straub, Wilson: a python package for the running and matching of Wilson coefficients above and below the electroweak scale, Eur. Phys. J. C 78 (2018) 1026 [arXiv:1804.05033] [INSPIRE].
Acknowledgments
We thank Aleks Smolkovič and Peter Stangl for numerical comparisons that lead to finding a bug in the original implementation of \( \overline{B}\to \left\{{\rho}^0,\omega \right\}\ell \overline{\nu} \) decays. M.R. thanks Admir Greljo for useful discussions on the paper. D.L., B.M. and D.v.D. acknowledge support from the Alexander von Humboldt Foundation in the framework of the Research Group Linkage Programme, funded by the German Federal Ministry of Education. B.M. has also been supported by the Croatian Science Foundation (HRZZ) project “Heavy hadron decays and lifetimes” (IP-2019-04-7094). D.v.D. acknowledges support by the U.K. Science and Technology Facilities Council (grant numbers ST/V003941/1 and ST/X003167/1).
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Leljak, D., Melić, B., Novak, F. et al. Toward a complete description of b → uℓ−\( \overline{\nu} \) within the Weak Effective Theory decays. J. High Energ. Phys. 2023, 63 (2023). https://doi.org/10.1007/JHEP08(2023)063
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DOI: https://doi.org/10.1007/JHEP08(2023)063