We present the analysis of exclusive $0^{ -}$$\to$$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 experimental data and the lattice QCD results. In addition, our model predicts the two unmeasured mass spectra of $^{ 1}S_{ 0}(b\bar{ b})$ and $^{ 3}S_{ 1}(b\bar{ s})$ systems as $M_{ b\bar{ b}}$=9657 MeV and $M_{ b\bar{ s}}$= 5424 MeV.
Categories: hep-ph