$B_u$ $\to$ $\psi M$ decays and $S$-$D$ wave mixing effects

Abstract

The $B_u$ $\to$ $\psi M$ decays are studied with the perturbative QCD approach, where the psion $\psi$ $=$ $\psi (2S)$, $\psi (3770)$, $\psi (4040)$ and $\psi (4160)$, and the light meson $M$ $=$ $\pi$, $K$, $\rho$ and $K^{\ast }$. The factorizable and nonfactorizable contributions, and the $S$-$D$ wave mixing effects on the psions are considered in the calculation. With appropriate inputs, the branching ratios for the $B_u$ $\to$ $\psi K$ decays are generally coincident with the experimental data within errors. However, due to the large theoretical and experimental errors, it is impossible for the moment to give a severe constraint on the $S$-$D$ wave mixing angles.

Comments: revtex, 29 pages, 4 figures