Light-front quark model analysis of exclusive 0^-→0^- semileptonic heavy meson decays

We present the analysis of exclusive 0^-→0^- semileptonic heavy meson decays using the constituent quark model based on the light-front quantization. Our model is constrained by the variational principle for the well-known linear plus Coulomb interaction motivated by QCD. Our method of analytic continuation to obtain the weak form factors avoids the difficulty associated with the contribution from the nonvalence quark-antiquark pair creation. Our numerical results for the heavy-to-heavy and heavy-to-light meson decays are in a good agreement with the available experi mental data and the lattice QCD results. In addition, our mode predicts the two unmeasured mass spectra of ¹S₀,(bb̄) and ³S₁(bs̄) systems as Mbb̄ = 9657 MeV and Mbs̄= 5424 MeV.