Relativistic description of the semileptonic decays of bottom mesons

Abstract

The form factors of the semileptonic $B$, $B_s$ and $B_c$ meson decays are calculated in the framework of the relativistic quark model based on the quasipotential approach in QCD. They are expressed through the overlap integrals of the meson wave function. All relativistic effects are consistently taken into account. The momentum transfer $q^2$ behavior of form factors is determined in the whole accessible kinematical range. We do not use any extrapolations, heavy quark $1/m_Q$ expansion or model assumptions about the shape of form factors. Convenient analytic expressions of the form factors are given, which very accurately reproduce the numerical results of our calculation. On the basis of these form factors and helicity formalism, the differential and total branching fractions of various semileptonic decays of bottom meson are calculated. The mean values of the forward-backward asymmetry $⟨A_{FB}⟩$, lepton-side convexity parameter $⟨C_F^{\ell }⟩$, longitudinal $⟨P_L^{\ell }⟩$ and transverse $⟨P_T^{\ell }⟩$ polarization of the charged lepton, and the longitudinal polarization fraction $⟨F_L⟩$ for final-state vector meson are also evaluated. We present a detailed comparison of the obtained predictions with the calculations based on the covariant light-front quark model and confront them to available lattice QCD and experimental data. It is found that although both models predict close values of the total branching fractions, the differential distributions and forward-backward asymmetry and polarization parameters differ significantly, especially for the heavy-to-light semileptonic decays. We identify observables which measurement can help to discriminate between models.

24 pages, 5 figures, minor changes, references added, version to appear in Physical Review D

References in corpus (18)

• Mass spectra and Regge trajectories of light mesons in the relativistic quark model
• $B\to \pi \ell \nu$ 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
• The B -> pi l nu semileptonic form factor from three-flavor lattice QCD: A model-independent determination of |V(ub)|
• Branching fraction and form-factor shape measurements of exclusive charmless semileptonic B decays, and determination of |V_{ub}|
• $B_s\to K\ell \nu$ form factors from lattice QCD
• Semitauonic $b$-hadron decays: A lepton flavor universality laboratory
• Challenges in Semileptonic B Decays
• Weak decays of $B_s$ mesons to $D_s$ mesons in the relativistic quark model
• Semileptonic decays of $D$ and $D_s$ mesons in the relativistic quark model
• $B_c\to J/\psi$ Form Factors for the full $q^2$ range from Lattice QCD
• New analysis of semileptonic B decays in the relativistic quark model
• Measurement of the $D^{\ast -}$ polarization in the decay $B^0\to D^{\ast -}{\tau }^{+}{\nu }_{\tau }$
• A comprehensive study on the semileptonic decay of heavy flavor mesons
• $B_s\to D_s^{\ast }$ Form Factors for the full $q^2$ range from Lattice QCD
• Heavy + heavy and heavy + light pseudoscalar to vector semileptonic transitions
• Form factors for the processes $B_c^{+}\to D^0{\ell }^{+}{\nu }_{\ell }$ and $B_c^{+}\to D_s^{+}{\ell }^{+}{\ell }^{-}(\nu \overline{\nu })$ from lattice QCD
• Weak transition form factors of heavy-light pseudoscalar mesons for space- and timelike momentum transfers
• New determination of $|V_{\mathrm{cb}}|$ using the three-loop QCD corrections for the $B\to D^{\ast }$ semi-leptonic decays

Cited by in corpus (12)

• Covariant Light-Front Approach for $B_c$ Decays into Charmonium: Implications on Form Factors and Branching Ratios
• Angular distribution of the FCNC process $B_c\to D_s^{\ast }(\to D_s\pi ){\ell }^{+}{\ell }^{-}$
• Systematic analysis of the form factors of $B_c\to {\eta }_c$, $J/\psi$ and corresponding weak decays
• Implications for the $\Delta A_{FB}$ anomaly in ${\bar{B}}^0\to D^{\ast +}{\ell }^{-}\bar{\nu }$ using a new Monte Carlo Event Generator
• Probing New Physics in light of recent developments in $b\to c\ell \nu$ transitions
• Prediction of various observables for $B_s^0\to D_s^{(\ast )-}{\ell }^{+}{\nu }_{\ell }$ within covariant confined quark model
• Exclusive semileptonic decays of $D$ and $D_s$ mesons into orbitally and radially excited states of strange and light mesons
• Systematic analysis of the transition form factors of $B_c$ to $D$-wave charmonia and corresponding semileptonic decays
• Study of charm and beauty mass spectra, semileptonic decays of $B_{(s,c)}$ and $B_c\to J/\psi ({\eta }_c)+P(V)$ in a phenomenological potential model
• Sensitivity of Two-Body Non-Leptonic Branching Fractions to Theoretical Mass Variations in Heavy-Light Mesons
• Exclusive semileptonic $B$ decays to the ground and excited states of light mesons
• Study of $B_c\to J/\psi (a_1(1260)$, $b_1(1235)$, $a_2(1320)$, $K_2^{\ast }(1430))$ decay with a perturbative QCD approach