Are there significant scalar resonances in $B^{-}\to D^{(*)0} K^{-} {K}^{0}$ decays?

Abstract

We study the indication of large different branching ratios between $B^{-}\to D^{(*)0} K^{-} {K}^{0}$ and $\bar{B}_{d}\to D^{(*)+} K^{-} {K}^{0}$ observed by Belle. Interestingly, the same situation is not found in the decays $B\to D^{(*)} K^{-} {K}^{*0}$. If there exist no intermediate resonances in the decays $B^{-}\to D^{(*)0} K^{-} {K}^{0}$, a puzzle will be arisen. We find that the color-suppressed processes $B^{-}\to D^{(*)0}a^{-}_{0}(1450)$ with $a^{-}_{0}(1450)\to K^{-} {K}^{0}$ could be one of the candidates to enhance the BRs of $B^{-}\to D^{(*)0} K^{-} {K}^{0}$. Our conjecture can be examined by the Dalitz plot technique and the analysis of angular dependence on $K^{-} {K}^{0}$ state at $B$ factories.