Non-factorizable long distance contributions in color suppressed decays of B mesons

Abstract

$\bar{B}\to D\pi$, $D^{\ast }\pi$, $J/\psi \bar{K}$ and $J/\psi \pi$ decays are studied. Their amplitude is given by a sum of factorized and non-factorizable ones. The latter which is estimated by using a hard pion approximation is rather small in color favored $\bar{B}\to D\pi$ and $D^{\ast }\pi$ decays but still can efficiently interfere with the main amplitude given by the factorization. In the color suppressed $\bar{B}\to J/\psi \bar{K}$ and $J/\psi \pi$ decays, the non-factorizable contribution is very important. The sum of the factorized and non-factorizable amplitudes can reproduce well the existing experimental data on the branching ratios for the color favored $\bar{B}\to D\pi$ and $D^{\ast }\pi$ and the color suppressed $\bar{B}\to J/\psi \bar{K}$ and $J/\psi \pi$ decays by taking reasonable values of unknown parameters involved.

Comments: 19 pages, Revtex