Improved measurement of the absolute branching fraction of $D^{+}\to {\bar{K}}^0\hat{I}{¼}^{+}\hat{I}{½}_{\hat{I}}¼$

Abstract

By analyzing 2.93 fb${}^{-1}$ of data collected at $\sqrt{s}=3.773$ GeV with the BESIII detector, we measure the absolute branching fraction $\mathcal{B}(D^{+}\to {\bar{K}}^0\hat{I}{¼}^{+}\hat{I}{½}_{\hat{I}}¼)=(8.72\pm 0.07_{stat.}\pm 0.18_{sys.})\%$, which is consistent with previous measurements within uncertainties but with significantly improved precision. Combining the Particle Data Group values of $\mathcal{B}(D^0\to K^{-}\hat{I}{¼}^{+}\hat{I}{½}_{\hat{I}}¼)$, $\mathcal{B}(D^{+}\to {\bar{K}}^0{e}^{+}\hat{I}{½}_e)$, and the lifetimes of the $D^0$ and $D^{+}$ mesons with the value of $\mathcal{B}(D^{+}\to {\bar{K}}^0\hat{I}{¼}^{+}\hat{I}{½}_{\hat{I}}¼)$ measured in this work, we determine the following ratios of partial widths: $\hat{I}“(D^0\to K^{-}\hat{I}{¼}^{+}\hat{I}{½}_{\hat{I}}¼)/\hat{I}“(D^{+}\to {\bar{K}}^0\hat{I}{¼}^{+}\hat{I}{½}_{\hat{I}}¼)=0.963\pm 0.044$ and $\hat{I}“(D^{+}\to {\bar{K}}^0\hat{I}{¼}^{+}\hat{I}{½}_{\hat{I}}¼)/\hat{I}“(D^{+}\to {\bar{K}}^0{e}^{+}\hat{I}{½}_e)=0.988\pm 0.033$.

9 pages; 8 figures