Measurements of the absolute branching fractions of the doubly Cabibbo-suppressed decays $D^{+}\to K^{+}\ddot{I}{€}^0$, $D^{+}\to K^{+}\hat{I}\cdot$ and $D^{+}\to K^{+}\hat{I}{\cdot }^{\prime }$

Abstract

Using $20.3\mathrm{f}{\mathrm{b}}^{-1}$ of $e^{+}{e}^{-}$ collision data collected at a center-of-mass energy of 3.773\,GeV with the BESIII detector, we present the measurements of the absolute branching fractions of the doubly Cabibbo-suppressed decays $D^{+}\to K^{+}\ddot{I}{€}^0$, $D^{+}\to K^{+}\hat{I}\cdot$ and $D^{+}\to K^{+}\hat{I}{\cdot }^{\prime }$ with the double-tag method, with significantly improved precision compared to the previous measurements. The statistical significance of each signal decay exceeds $10\ddot{I}ƒ$. The branching fractions are determined to be $\mathcal{B}(D^{+}\to K^{+}\ddot{I}{€}^0)=(1.45\pm 0.06\pm 0.08)\times 10^{-4}$, $\mathcal{B}(D^{+}\to K^{+}\hat{I}\cdot )=(1.17\pm 0.10\pm 0.03)\times 10^{-4}$ and $\mathcal{B}(D^{+}\to K^{+}\hat{I}{\cdot }^{\prime })=(1.88\pm 0.15\pm 0.11)\times 10^{-4}$, where the first uncertainties are statistical and the second systematic. The branching fractions of $D^{+}\to K^{+}\hat{I}\cdot$ and $D^{+}\to K^{+}\hat{I}{\cdot }^{\prime }$ are consistent with the world average values. The reported branching fraction of $D^{+}\to K^{+}\ddot{I}{€}^0$ deviates with the world average value by 3$\ddot{I}ƒ$.

20 pages, 4 figures