$B\to D{K}_{0,2}^{\ast }$ Decays: PQCD analysis to determine CP violation phase angle $\gamma$

Abstract

$B^{\pm }\to (D^0,{\bar{D}}^0,D_{CP})K_{0,2}^{\ast \pm }$ decays are helpful in determining the CP violation angle $\gamma$, and we analyze these decay processes within the perturbative QCD approach based on $k_T$ factorization. We found that the branching ratio of $B^{-}\to D^0{K}_0^{\ast -}$ can reach the order of $10^{-4}$, due to the enhancement of nonfactorizable contributions in color-suppressed $D^0$-emission, while the branching ratio of $B^{-}\to {\bar{D}}^0{K}_0^{\ast -}$ is of the order $10^{-5}$. The ratio of decay amplitudes is about 3 times larger than the one in the channel $B^{\pm }\to D{K}^{\pm }$. Large branching ratios provide a good opportunity to observe $B^{\pm }\to D{K}_2^{\ast \pm }$ on the ongoing and forthcoming experimental facilities and consequently these channels may be of valuable avail in reducing the errors in the CP violation phase angle $\gamma$. We also explore the possible time-dependent CP asymmetries of $B_s$ decay into a scalar meson to determine the phase angle $\gamma$.

Comments: 7 pages, 2 figures