The doubly Cabibbo-suppressed decay $D^{+}\to K^{+}{\pi }^{-}{\pi }^{+}$

Abstract

We report the observation of the doubly Cabibbo-suppressed decay $D^{+}\to K^{+}{\pi }^{-}{\pi }^{+}$ in data from Fermilab charm hadroproduction experiment E791. With a signal of 59 \pm 13 events we measured the ratio of the branching fraction for this mode to that of the Cabibbo-favored decay $D^{+}\to K^{-}{\pi }^{+}{\pi }^{+}$ to be $B(D^{+}\to K^{+}{\pi }^{-}{\pi }^{+})/B(D^{+}\to K^{-}{\pi }^{+}{\pi }^{+})=(7.7\pm 1.7\pm 0.8)\times 10^{-3}$. A Dalitz plot analysis was performed to search for resonant structures.

10 pages, 5 eps figures, RevTex