Search for $D^0\to K_S^0{K}^{-}{e}^{+}\hat{I}{½}_e$, $D^{+}\to K_S^0{K}_S^0{e}^{+}\hat{I}{½}_e$, and $D^{+}\to K^{+}{K}^{-}{e}^{+}\hat{I}{½}_e$

Abstract

A search has been performed for the semileptonic decays $D^0\to K_S^0{K}^{-}{e}^{+}\hat{I}{½}_e$, $D^{+}\to K_S^0{K}_S^0{e}^{+}\hat{I}{½}_e$ and $D^{+}\to K^{+}{K}^{-}{e}^{+}\hat{I}{½}_e$, using $7.9{\mathrm{fb}}^{-1}$ of $e^{+}{e}^{-}$ annihilation data collected at the center-of-mass energy $\sqrt{s}=3.773$ GeV by the BESIII detector operating at the BEPCII collider. No significant signals are observed, and upper limits are set at the 90\% confidence level of $2.13\times 10^{-5}$, $1.54\times 10^{-5}$ and $2.10\times 10^{-5}$ for the branching fractions of $D^0\to K_S^0{K}^{-}{e}^{+}\hat{I}{½}_e$, $D^{+}\to K_S^0{K}_S^0{e}^{+}\hat{I}{½}_e$ and $D^{+}\to K^{+}{K}^{-}{e}^{+}\hat{I}{½}_e$, respectively.

10 pages, 3 figures