Exclusive semileptonic $B_s\to K\ell \nu$ decays on the lattice

Abstract

Semileptonic $B_s\to K\ell \nu$ decays provide an alternative $b$-decay channel to determine the CKM matrix element $|V_{ub}|$, and to obtain a $R$-ratio to investigate lepton-flavor-universality violations. Results for the CKM matrix element may also shed light on the discrepancies seen between analyses of inclusive or exclusive decays. We calculate the decay form factors using lattice QCD with domain-wall light quarks and a relativistic $b$-quark. We analyze data at three lattice spacings with unitary pion masses down to $268\mathrm{MeV}$. Our numerical results are interpolated/extrapolated to physical quark masses and to the continuum to obtain the vector and scalar form factors $f_{+}(q^2)$ and $f_0(q^2)$ with full error budgets at $q^2$ values spanning the range accessible in our simulations. We provide a possible explanation of tensions found between results for the form factor from different lattice collaborations. Model- and truncation-independent $z$-parameterization fits following a recently proposed Bayesian-inference approach extend our results to the entire allowed kinematic range. Our results can be combined with experimental measurements of $B_s\to D_s$ and $B_s\to K$ semileptonic decays to determine $|V_{ub}|=3.8(6)\times 10^{-3}$. The error is currently dominated by experiment. We compute differential branching fractions and two types of $R$ ratios, the one commonly used as well as a variant better suited to test lepton-flavor universality.

arXiv commentVersion accepted and published (Phys. Rev. D 107, 114512) 30 pages, 13 Figures, supplementary data file

References in corpus (105)

• A Method for Simulating Chiral Fermions on the Lattice
• Test of lepton universality using $B^{+}\to K^{+}{\ell }^{+}{\ell }^{-}$ decays
• On the Viability of Lattice Perturbation Theory
• Evidence for an excess of B -> D(*) Tau Nu decays
• The Chroma Software System for Lattice QCD
• Chiral Fermions from Lattice Boundaries
• Phenomenology of Heavy Meson Chiral Lagrangians
• Measurement of an Excess of B -> D(*) Tau Nu Decays and Implications for Charged Higgs Bosons
• FLAG Review 2019
• Measurement of the branching ratio of $\bar{B}\to D^{(\ast )}{\tau }^{-}{\bar{\nu }}_{\tau }$ relative to $\bar{B}\to D^{(\ast )}{\ell }^{-}{\bar{\nu }}_{\ell }$ decays with hadronic tagging at Belle
• RunDec: a Mathematica package for running and decoupling of the strong coupling and quark masses
• Measurement of the ratio of branching fractions $\mathcal{B}({\overline{B}}^0\to D^{\ast +}{\tau }^{-}{\overline{\nu }}_{\tau })/\mathcal{B}({\overline{B}}^0\to D^{\ast +}{\mu }^{-}{\overline{\nu }}_{\mu })$
• Axial symmetries in lattice QCD with Kaplan fermions
• FLAG Review 2021
• Measurement of form-factor independent observables in the decay $B^0\to K^{\ast 0}{\mu }^{+}{\mu }^{-}$
• Chiral Multiplets of Heavy-Light Mesons
• Massive Fermions in Lattice Gauge Theory
• The QCD spectrum with three quark flavors
• Dispersive Bounds on the Shape of B -> D^(*) l nu Form Factors
• Averages of $b$-hadron, $c$-hadron, and $\tau$-lepton properties as of 2021
• Domain wall QCD with physical quark masses
• Model-independent description of $B\to \pi l\nu$ decays and a determination of $|V_{ub}|$
• Excited Heavy-Light Systems and Hadronic Transitions
• Physical Results from 2+1 Flavor Domain Wall QCD and SU(2) Chiral Perturbation Theory
• Constraints on Form Factors For Exclusive Semileptonic Heavy to Light Meson Decays
• Continuum Limit Physics from 2+1 Flavor Domain Wall QCD
• Charm and Bottom Quark Masses: an Update
• Version 3 of {\tt RunDec} and {\tt CRunDec}
• Flavor models for $\bar{B}\to D^{(\ast )}\tau \bar{\nu }$
• Heavy-light meson spectroscopy and Regge trajectories in the relativistic quark model
• Precision Corrections to Dispersive Bounds on Form Factors
• $B\to Dl\nu$ Form Factors at Non-Zero Recoil and Extraction of $|V_{cb}|$
• Revisiting $B\to D\ell \nu$
• On meson resonances and chiral symmetry
• Theory of Charmless Inclusive B Decays and the Extraction of V_{ub}
• $|V_{ub}|$ from $B\to \pi \ell \nu$ decays and (2+1)-flavor lattice QCD
• Study of B --> pi l nu and B --> rho l nu Decays and Determination of |V_ub|
• $B\to \pi \ell \nu$ and $B_s\to K\ell \nu$ form factors and $|V_{ub}|$ from 2+1-flavor lattice QCD with domain-wall light quarks and relativistic heavy quarks
• Study of Exclusive B->X_u l nu Decays and Extraction of |V_{ub}| using Full Reconstruction Tagging at the Belle Experiment
• Inclusive semileptonic B decays and the determination of |V_ub|
• Improved Theory Predictions and Global Analysis of Exclusive $\mathbf{b}\to \mathbf{s}{\mathbf{\mu }}^{+}{\mathbf{\mu }}^{-}$ Processes
• A Precision Model Independent Determination of |Vub| from B -> pi e nu
• Inclusive spectra in charmless semileptonic B decays by Dressed Gluon Exponentiation
• Lattice QCD calculation of $\bar{B}\to Dl\bar{\nu }$ decay form factors at zero recoil
• Measurement of the decay $B^0\to {\pi }^{-}{\ell }^{+}\nu$ and determination of $|V_{ub}|$
• Analysis of the masses and decay constants of the heavy-light mesons with QCD sum rules
• CRunDec: a C++ package for running and decoupling of the strong coupling and quark masses
• Branching fraction and form-factor shape measurements of exclusive charmless semileptonic B decays, and determination of |V_{ub}|
• Lattice-Constrained Unitarity Bounds for ${\bar{B}}^0\to {\pi }^{+}{l}^{-}{\bar{\nu }}_l$ Decays
• Non-local matrix elements in $B_{(s)}\to \{K^{(\ast )},\varphi \}{\ell }^{+}{\ell }^{-}$
• The semileptonic decays $B/B_s\to (\pi ,K)(l^{+}{l}^{-},l\nu ,\nu \bar{\nu })$ in the perturbative QCD approach beyond the leading-order
• The Semileptonic Decays $B\to \pi l\nu$ and $D\to \pi l\nu$ from Lattice QCD
• $B_s\to K\ell \nu$ form factors from lattice QCD
• $B$ and $B_s$ Meson Spectroscopy
• Relativistic Heavy Quark Effective Action
• QCD with domain wall quarks
• $B_s\to K\ell {\nu }_{\ell }$ and $B_{(s)}\to \pi (K){\ell }^{+}{\ell }^{-}$ decays at large recoil and CKM matrix elements
• Analyticity, Shapes of Semileptonic Form Factors, and B to pi l nu
• Spectra and M1 Decay Widths of Heavy-Light Mesons
• Excited bottom and bottom-strange mesons in the quark model
• Chiral Logs in the Presence of Staggered Flavor Symmetry Breaking
• Domain wall quarks and kaon weak matrix elements
• Leading isospin-breaking corrections to pion, kaon and charmed-meson masses with Twisted-Mass fermions
• New lattice action for heavy quarks
• Higher bottom and bottom-strange mesons
• A Canonical Ds(2317)?
• The Low Energy Constants of $SU(2)$ Partially Quenched Chiral Perturbation Theory from $N_f=2+1$ Domain Wall QCD
• Heavy meson chiral perturbation theory in finite volume
• B, Bs -> K form factors: an update of light-cone sum rule results
• SU(2) chiral perturbation theory low-energy constants from 2+1 flavor staggered lattice simulations
• QCD Parameters Correlations from Heavy Quarkonia
• Lattice QCD at the physical point meets SU(2) chiral perturbation theory
• Non-perturbatively Determined Relativistic Heavy Quark Action
• The decay constants ${\mathbf{f}}_{\mathbf{D}}$ and ${\mathbf{f}}_{{\mathbf{D}}_{\mathbf{s}}}$ in the continuum limit of ${\mathbf{N}}_{\mathbf{f}}=2+1$ domain wall lattice QCD
• New Heavy-Light Mesons $Q\bar{q}$
• Application of heavy-quark effective theory to lattice QCD: II. Radiative corrections to heavy-light currents
• Semileptonic $B_{(s)}$ decays to excited charmed mesons with $e,\mu ,\tau$ and searching for new physics with $R(D^{\ast \ast })$
• Nonperturbative tuning of an improved relativistic heavy-quark action with application to bottom spectroscopy
• B-meson decay constants from 2+1-flavor lattice QCD with domain-wall light quarks and relativistic heavy quarks
• $B_s\to K\ell \nu$ decay from lattice QCD
• Heavy-Light Semileptonic Decays in Staggered Chiral Perturbation Theory
• Bounding effective parameters in the chiral Lagrangian for excited heavy mesons
• ${\mathbf{B}}_{\mathbf{s}}\to {\mathbf{K}}^{(\ast )}\mathbf{\ell }\bar{\nu }$, Angular Analysis, S-wave Contributions and $|{\mathbf{V}}_{\mathbf{ub}}|$
• Chiral condensate from the twisted mass Dirac operator spectrum
• Hard Pion Chiral Perturbation Theory for $B\to \pi$ and $D\to \pi$ Formfactors
• First observation of the decay $B_s^0\to K^{-}{\mu }^{+}{\nu }_{\mu }$ and a measurement of $|V_{ub}|/|V_{cb}|$
• Moments of heavy quark correlators with two masses: exact mass dependence to three loops
• Charmless weak $B_s$ decays in the relativistic quark model
• SU(2) chiral perturbation theory for Kl3 decay amplitudes
• Open bottom states and the anti-B meson propagation in hadronic matter
• B-->pi and B-->K transitions in standard and quenched chiral perturbation theory
• The chiral transitions in heavy-light mesons
• Topological susceptibility from twisted mass fermions using spectral projectors and the gradient flow
• Masses of Scalar and Axial-Vector B Mesons Revisited
• B meson spectroscopy
• Near Mass Degeneracy in the Scalar Meson Sector: Implications for $B_{(s)0}^{\ast }$ and $B_{(s)1}^{\prime }$ Mesons
• The B*Bpi coupling using relativistic heavy quarks
• Spectra of heavy-light mesons in a relativistic model
• Why there is no spin-orbit inversion in heavy-light mesons?
• The D234 action for light quarks
• Continuum limit of the leading order HQET form factor in $B_s\to K\ell \nu$ decays
• Model-Independent Prediction of $R({\eta }_c)$
• Form factor ratios for $B_s\to K\ell \nu$ and $B_s\to D_s\ell \nu$ semileptonic decays and $|V_{ub}/V_{cb}|$
• Topological susceptibility of QCD with dynamical Möbius domain wall fermions
• Optimized Lepton Universality Tests in $B\to V\ell \bar{\nu }$ decays

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• FLAG Review 2024
• ${\Xi }_c\to \Xi$ form factors from lattice QCD with domain-wall quarks: A new piece in the puzzle of ${\Xi }_c^0$ decay rates
• Exploring the exclusive decay $B^{+}\to \omega {\ell }^{+}\nu$ with light-cone sum rules
• ${\Xi }_b\to \Xi$ form factors from lattice QCD and Standard-Model predictions for ${\Xi }_b\to \Xi {\mu }^{+}{\mu }^{-}$ and ${\Xi }_b\to \Xi \gamma$ decays
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