Study of D^{+} and D_{s}^{+} Decay Properties at Belle

Abstract

We report the first observation of the doubly Cabibbo-suppressed decay, $D_s^{+}\to K^{+}{K}^{+}{\pi }^{-}$ and the significantly improved measurement of the doubly Cabibbo-suppressed decay, $D^{+}\to K^{+}{\pi }^{+}{\pi }^{-}$ using ${\text{605 fb}}^{-1}$ of data collected with the Belle detector at the KEKB asymmetric-energy $e^{+}{e}^{-}$ collider. The branching ratio with respect to its Cabibbo-favored counterpart are $\mathcal{B}(D_s^{+}\to K^{+}{K}^{+}{\pi }^{-})/\mathcal{B}(D_s^{+}\to K^{+}{K}^{-}{\pi }^{+})=0.229\pm 0.028\pm 0.012)$ and $\mathcal{B}(D^{+}\to K^{+}{\pi }^{+}{\pi }^{-})/\mathcal{B}(D^{+}\to K^{-}{\pi }^{+}{\pi }^{+})=(0.569\pm 0.018\pm 0.014)$, where the first uncertainties are statistical and the second is systematic. We also report the improved measurement of $D^{+}\to K_S^0{K}^{+}$ and $D_s^{+}\to K_S^0{\pi }^{+}$ branching ratios using the same amount of data samples. The measured branching ratios with respect to the Cabibbo-favored modes are $\mathcal{B}(D^{+}\to K_S^0{K}^{+})/\mathcal{B}(D^{+}\to K_S^0{\pi }^{+})=(0.1899\pm 0.0011\pm 0.0018)$ and $\mathcal{B}(D_s^{+}\to K_S^0{\pi }^{+})/\mathcal{B}(D_s^{+}\to K_S^0{K}^{+})=(0.0803\pm 0.0024\pm 0.0012)$.

To be published in the proceedings of DPF-2009, Detroit, MI, July 2009, eConf C090726