Factorization and SU(2) heavy flavor symmetry for B-meson decays producing charmonium.

Abstract

We show that the factorization assumption in color-suppressed $B$ meson decays is not ruled out by experimental data on $B \ra K(K^*) + J/\Psi(\Psi^{'})$. The problem previously pointed out might be due to an inadequate choice of hadronic form factors. Within the Isgur-Wise SU(2) heavy flavor symmetry framework, we search for possible $q^2$ dependence of form factors that are capable of explaining simultaneously the large longitudinal polarization $\rho_L$ observed in $B \ra K^* + J/\Psi$ and the relatively small ratio of rates $R_{J/\Psi} = \Gamma(B \ra K^* + J/\Psi)/\Gamma(B \ra K + J/\Psi)$. We find out that the puzzle could be essentially understood if the $A_1(q^2)$ form factor is frankly decreasing, instead of being almost constant or increasing as commonly assumed. Of course, the possibility of understanding experimental data is not necessarily a proof of factorization.