Precision Corrections to Dispersive Bounds on Form Factors

Abstract

We present precision corrections to dispersion relation bounds on form factors in bottom hadron semileptonic decays and analyze their effects on parameterizations derived from these bounds. We incorporate QCD two-loop and nonperturbative corrections to the two-point correlator, consider form factors whose contribution to decay rates is suppressed by lepton mass, and implement more realistic estimates of truncation errors associated with the parameterizations. We include higher resonances in the hadronic sum that, together with heavy quark symmetry relations near zero recoil, further tighten the sum rule bounds. Utilizing all these improvements, we show that each of the six form factors in B --> D l nu and B --> D^* l nu can be described with 3% or smaller precision using only the overall normalization and one unknown parameter. A similar one-coefficient parameterization of one of the Lambda_b --> Lambda_c l nu form factors, together with heavy quark symmetry relations valid to order 1/m^2, describes the differential baryon decay rate in terms of one unknown parameter and the phenomenologically interesting quantity (\bar Lambda)_Lambda \approx M_{Lambda_b} - m_b. We discuss the validity of slope-curvature relations derived by Caprini and Neubert, and present weaker, corrected relations. Finally, we present sample fits of current experimental B --> D^*l nu and B --> D l nu data to the improved one-parameter expansion.

45 pages, RevTeX. Version to appear in Phys. Rev. D. Improved statistical analysis reveals that our fit is competitive with ad hoc parameterizations

References in corpus (2)

• Analyticity, Shapes of Semileptonic Form Factors, and B to pi l nu
• Theoretical Aspects of the Heavy Quark Expansion

Cited by in corpus (150)

• FLAG Review 2019
• FLAG Review 2021
• Averages of $b$-hadron, $c$-hadron, and $\tau$-lepton properties as of 2018
• 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
• Combined analysis of semileptonic $B$ decays to $D$ and $D^{\ast }$: $R(D^{(\ast )})$, $|V_{cb}|$, and new physics
• The lifetime of the $B_c^{-}$ meson and the anomalies in $B\to D^{(\ast )}\tau \nu$
• Revisiting $B\to D\ell \nu$
• $R(D^{\ast })$, $|V_{cb}|$, and the Heavy Quark Symmetry relations between form factors
• Measurement of the $\tau$ lepton polarization and $R(D^{\ast })$ in the decay $\bar{B}\to D^{\ast }{\tau }^{-}{\bar{\nu }}_{\tau }$ with one-prong hadronic $\tau$ decays at Belle
• 50 Years of Quantum Chromodynamics
• Scalar contributions to $b\to c(u)\tau \nu$ transitions
• Extraction of $|V_{cb}|$ from $B\to D^{(\ast )}\ell {\nu }_{\ell }$ and the Standard Model predictions of $R(D^{(\ast )})$
• A fresh look at the determination of |V_cb| from B-> D^* l nu
• The $V_{cb}$ puzzle: an update
• Global fit to $b\to c\tau \nu$ transitions
• Precise Calculation of the Dilepton Invariant-Mass Spectrum and the Decay Rate in $B^{\pm }\to {\pi }^{\pm }{\mu }^{+}{\mu }^{-}$ in the SM
• Charged-Higgs effects in a new B -> D tau nu differential decay distribution
• Charm Meson Decays
• Measurement of the CKM Matrix Element $|V_{cb}|$ from $B^0\to D^{\ast -}{\ell }^{+}{\nu }_{\ell }$ at Belle
• Model-Independent Extraction of $|V_{cb}|$ from $\bar{B}\to D^{\ast }\ell \overline{\nu }$
• Constraining new physics in $b\to c\ell \nu$ transitions
• Measurement of |V_cb| and the Form-Factor Slope in Bbar -> D l- nubar Decays in Events Tagged by a Fully Reconstructed B Meson
• $B\to D^{(\ast )}$ Form Factors from QCD Light-Cone Sum Rules
• Semileptonic form factors for $B\to D^{\ast }\ell \nu$ at nonzero recoil from 2 + 1-flavor lattice QCD
• Bayesian fit analysis to full distribution data of $\bar{B}\to D^{(\ast )}\ell \bar{\nu }$: $|V_{cb}|$ determination and New Physics constraints
• FLAG Review 2024
• Tau properties in $B\to D\tau \nu$ from visible final-state kinematics
• $D^{\ast }$ polarization vs. $R_{D^{(\ast )}}$ anomalies in the leptoquark models
• Lattice QCD calculation of the $B_{(s)}\to D_{(s)}^{\ast }\ell \nu$ form factors at zero recoil and implications for $|V_{cb}|$
• Measurement of the ratios of branching fractions $\mathcal{R}(D^{\ast })$ and $\mathcal{R}(D^0)$
• Semitauonic $b$-hadron decays: A lepton flavor universality laboratory
• Challenges in Semileptonic B Decays
• Precise predictions for ${\Lambda }_b\to {\Lambda }_c$ semileptonic decays
• New predictions for ${\Lambda }_b\to {\Lambda }_c$ semileptonic decays and tests of heavy quark symmetry
• B_s->D_s/B->D Semileptonic Form-Factor Ratios and Their Application to BR(B^0_s->μ^+μ^-)
• Dispersive Analysis of $B\to K^{(\ast )}$ and $B_s\to \varphi$ Form Factors
• Lepton-flavour non-universality of $\bar{B}\to D^{\ast }\ell \bar{\nu }$ angular distributions in and beyond the Standard Model
• $|V_{cb}|$ and $R(D^{(\ast )})$ using lattice QCD and unitarity
• The role of right-handed neutrinos in $b\to c\tau \bar{\nu }$ anomalies
• $B_c\to J/\psi$ Form Factors for the full $q^2$ range from Lattice QCD
• Tensions and correlations in $|V_{cb}|$ determinations
• New analysis of semileptonic B decays in the relativistic quark model
• Flavor Anomalies in Heavy Quark Decays
• Extraction of form Factors from a Four-Dimensional Angular Analysis of $\overline{B}\to D^{\ast }{\ell }^{-}{\overline{\nu }}_{\ell }$
• Finding the sigma pole by analytic extrapolation of $\pi \pi$ scattering data
• Measurement of Br(Bbar -> D+l-nubar) and Determination of |Vcb|
• Measurement of the $B\to D\ell \nu$ Branching Fractions and Form Factor
• Unitarity Bounds for Semileptonic Decays in Lattice QCD
• Revisit to the $b\to c\tau \nu$ transition: in and beyond the SM
• Moments of the B Meson Inclusive Semileptonic Decay Rate using Neutrino Reconstruction
• Precision calculations of $B_{d,s}\to \pi ,K$ decay form factors in soft-collinear effective theory
• Constraints for the semileptonic $B\to D^{(\ast )}$ form factors from lattice QCD simulations of two-point correlation functions
• Lower bounds on the curvature of the Isgur-Wise function
• Study of the leptonic decays of pseudoscalar $B,D$ and vector $B^{\ast },D^{\ast }$ mesons and of the semileptonic $B\to D$ and $B\to D^{\ast }$ decays
• Form factors of $B\to \pi \ell \nu$ and a determination of $|V_{ub}|$ with Möbius domain-wall-fermions
• Measurement of V_{cb} from the decay process \bar{B^0} -> D^{*+} \ell^- \barν
• Evading the CKM Hierarchy: Intrinsic Charm in B Decays
• Measurement of Differential Distributions of $B\to D^{\ast }\ell {\bar{\nu }}_{\ell }$ and Implications on $|V_{cb}|$
• Model-Independent Bounds on $R(J/\psi )$
• Determination of |Vcb| using the semileptonic decay \bar{B}^0 --> D^{*+}e^-\barν
• Das ist der HAMMER: Consistent new physics interpretations of semileptonic decays
• Phenomenology of $b\to c\tau \bar{\nu }$ decays in a scalar leptoquark model
• Heavy Flavour Physics and CP Violation at LHCb: a Ten-Year Review
• Measurement of the Lambda_b^0 Decay Form Factor
• $B\to D\ell {\nu }_{\ell }$ form factors beyond leading power and extraction of $|V_{cb}|$ and $R(D)$
• Exclusive determinations of $|V_{cb}|$ and $R(D^{\ast })$ through unitarity
• Model independent investigation of the $R_{J/\psi ,{\eta }_c}$ and ratios of decay widths of semileptonic $B_c$ decays into a P-wave charmonium
• Heavy quark symmetry in B -> D(*) ell nu spectra
• $B\to D^{\ast }\ell {\nu }_{\ell }$ semileptonic form factors from lattice QCD with Möbius domain-wall quarks
• Measurement of |V_cb| using the semileptonic decay anti-B0d -> D*+ l- anti-nu_l
• Determination of the B-bar --> D* l nu-bar Decay Width and |V_cb|
• Improved Measurement of |Vcb| using B --> D* l nu Decays
• Revisiting fits to $B^0\to D^{\ast -}{\ell }^{+}{\nu }_{\ell }$ to measure $|V_{cb}|$ with novel methods and preliminary LQCD data at non-zero recoil
• Precision Model-Independent Bounds from Global Analysis of $b\to c\ell \nu$ Form Factors
• $B_s\to D_s^{\ast }$ Form Factors for the full $q^2$ range from Lattice QCD
• N = 5, 6, 7, 8: Nested hypothesis tests and truncation dependence of $|V_{cb}|$
• $|V_{cb}|$, Lepton Flavour Universality and $SU(3{)}_F$ symmetry breaking in $B_s\to D_s^{(\ast )}\ell {\nu }_{\ell }$ decays through unitarity and lattice QCD
• Discriminating $B\to D^{\ast }\ell \nu$ form factors via polarization observables and asymmetries
• Model-Independent Determination of $B_c^{+}\to {\eta }_c{\ell }^{+}\nu$ Form Factors
• $B\to \rho l\bar{\nu }$ and $\omega l\bar{\nu }$ in and beyond the Standard Model: Improved predictions and $|V_{ub}|$
• Bounds on the derivatives of the Isgur-Wise function from sum rules in the heavy quark limit of QCD
• B Meson Decays
• The $D_s$-meson leading-twist distribution amplitude within the QCD sum rules and its application to the $B_s\to D_s$ transition form factor
• Exclusive semileptonic $B_s\to K\ell \nu$ decays on the lattice
• Determination of $|V_{cb}|$ using ${\overline{B}}^0\to D^{\ast +}{\ell }^{-}{\bar{\nu }}_{\ell }$ decays with Belle II
• Lepton Flavor Universality tests through angular observables of $\overline{B}\to D^{(\ast )}\ell \overline{\nu }$ decay modes
• Tests of the Standard Model in $B\to D\ell {\nu }_{\ell }$, $B\to D^{\ast }\ell {\nu }_{\ell }$ and $B_c\to J/\psi \ell {\nu }_{\ell }$
• New Constraints on Dispersive Form Factor Parameterizations from the Timelike Region
• Model-Independent Prediction of $R({\eta }_c)$
• Measurement of the shape of the $B_s^0\to D_s^{\ast -}{\mu }^{+}{\nu }_{\mu }$ differential decay rate
• Updated evaluation of ${\epsilon }_K$ in the Standard Model with lattice QCD inputs
• Measurement of the B0bar --> D*+ l- nubar_l Decay Rate and |Vcb|
• Measurement of the branching fraction ratios $R(D^{+})$ and $R(D^{\ast +})$ using muonic $\tau$ decays
• B^+ --> D^{*+}_s gamma and B^+ --> D^{*+} gamma as Probes of V_{ub}
• Unitarity bounds with subthreshold and anomalous cuts for $b$-hadron decays
• Extractions of $|V_{ub}|/|V_{cb}|$ from a combined study of the exclusive $b\to u(c)\ell {\nu }_{\ell }$ decays
• Semileptonic form factors - a model-independent approach
• Implications of unitarity and analyticity for the Dπform factors
• Scrutinizing New Physics in Semi-leptonic $B_c\to J/\psi \tau \nu$ Decay
• On sum rules for semi-leptonic $b\to c$ and $b\to u$ decays
• Perturbative corrections to curvature sum rules
• Relations among $B_c\to J/\psi ,{\eta }_c$ form factors
• Bound on the curvature of the Isgur-Wise function of the baryon semileptonic decay Lambda_b -> Lambda_c + l + nu
• Dispersive Bounds on The Shape Of Lambda_b to Lambda_c l {\bar ν_l} Formfactors
• Measurement of the $D^{\ast }$ longitudinal polarization in $B^0\to D^{\ast -}{\tau }^{+}{\nu }_{\tau }$ decays
• New parametrization of the form factors in $\bar{B}\to D\ell {\bar{\nu }}_{\ell }$ decays
• Study of $B\to \pi \ell {\nu }_{\ell }$ and $B^{+}\to {\eta }^{(\prime )}{\ell }^{+}{\nu }_{\ell }$ decays and determination of $|V_{ub}|$
• Next-to-leading order QCD calculation of $B_c$ to charmonium tensor form factors
• Implications for the $\Delta A_{FB}$ anomaly in ${\bar{B}}^0\to D^{\ast +}{\ell }^{-}\bar{\nu }$ using a new Monte Carlo Event Generator
• $b\to c\tau \bar{\nu }$ decays in supersymmetry with $R$-parity violation
• Continuity and Semileptonic $B_{(s)}\to D_{(s)}$ Form Factors
• Constraining $|V_{cs}|$ and physics beyond the Standard Model from exclusive (semi)leptonic charm decays
• Model-independent constraints on hadronic form factors with above-threshold poles
• Determination of $f_{+}^{\pi }(0)$ and Extraction of $|V_{cd}|$ from Semileptonic $D$ Decays
• The Phenomenology of Inclusive Heavy-to-Light Sum Rules
• Above-Threshold Poles in Model-Independent Form Factor Parametrizations
• The forward-backward asymmetry and differences of partial moments in inclusive semileptonic B decays
• Improved Unitarity Bounds for B -> Pi Decays
• Density distributions in the $B$ meson
• Revisiting $D$-meson twist-2, 3 distribution amplitudes
• Baryonic heavy-to-light form factors induced by tensor current in light-front approach
• Determinations of $|V_{cb}|$ and $|V_{ub}|$ from baryonic ${\Lambda }_b$ decays
• Test of lepton flavor universality with measurements of $R(D^{+})$ and $R(D^{\ast +})$ using semileptonic $B$ tagging at the Belle II experiment
• A model-independent parameterization of $B\to \pi \pi \ell \nu$ decays
• Consistency constraints on m_s from QCD dispersion relations and chiral perturbation theory in K_{l3} decays
• $B\to D^{\ast }\ell \nu$ at non-zero recoil
• An Imperative study of the angular observables in ${\Lambda }_b\to {\Lambda }_c^{+}(\to \Lambda {\pi }^{+}){\ell }^{-}{\bar{\nu }}_{\ell }$ decay and probing the footprint of new physics
• Relations between $b\to c\tau \nu$ Decay Modes in Scalar Models
• Model-independent constraint on the pion scalar form factor and light quark masses
• Experimental Status of the CKM Matrix
• Impact on $L$-observables of a new combined analysis of $B_{d,s}\to K^{(\ast )}$ form factors
• Static and dynamic properties of hadronic systems with heavy quarks b and c
• New determination of $|V_{\mathrm{cb}}|$ using the three-loop QCD corrections for the $B\to D^{\ast }$ semi-leptonic decays
• Advanced parametrisations for hadronic form factors
• Hint of a new scalar interaction in LHCb data?
• Recent progress in decays of $b$ and $c$ hadrons
• The nonfactorizable QED correction to the ${\overline{B}}_s$ $\to$ $D_s^{(\ast )}\ell {\bar{\nu }}_{\ell }$ decays
• Extraction of $|V_{cb}|$ from two-body hadronic B decays
• Bounds on Heavy-to-Heavy Mesonic Form Factors
• Higgs hunting with B decays
• Prospects for $B_c^{+}\to {\tau }^{+}{\nu }_{\tau }$ at FCC-ee
• Meson exchange between initial and final state and the $R_D$ ratio in the $\bar{B}\to D\bar{\nu }\ell ({\bar{\nu }}_{\tau }\tau )$ reactions
• Determination of $B$-meson distribution amplitudes from $B\to \pi ,K,D$ transition form factors
• Study of $B^{+}\to {\mu }^{+}{\nu }_{\mu }$ decays at Belle and Belle II
• On magnitudes of some CKM matrix elements
• Study of Form Factors and Observables in $B_c^{-}\to {\bar{D}}^{(\ast )0}{\ell }^{-}{\bar{\nu }}_{\ell }$ and $B_c^{-}\to D^{(\ast )-}{\ell }^{+}{\ell }^{-}$ decays
• Remarks on Form Factor Bounds
• Heavy Meson Physics: What have we learned in Twenty Years?
• Joint LHCb--Belle II Prospects to Constrain New Physics in $B\to D^{(\ast )}\tau \nu$