Measurement of $D^0-{\bar{D}}^0$ mixing parameters using semileptonic decays of neutral kaon

Abstract

We propose a new method to extract $D^0-{\bar{D}}^0$ mixing parameters using the $D^0\to \bar{K}{}^0{\pi }^0$ decay with the $\bar{K}{}^0$ reconstructed in the semileptonic mode. Although a $K^0\to {\pi }^{\pm }{l}^{\mp }{\nu }_l$ decay suffers from low statistics and complexity of the secondary vertex reconstruction in comparison to the standard $K_S\to {\pi }^{+}{\pi }^{-}$ vertex, it provides much richer, sometimes unique information about the initial state of a $K^0$-meson produced in a heavy-flavor hadron decay. In this paper it is shown that the reconstruction of the chain $D^0\to K^0({\pi }^{\pm }{l}^{\mp }{\nu }_l){\pi }^0$ allows one to extract the strong phase difference between the doubly Cabibbo-suppressed and Cabibbo-favored decay amplitudes, which is of key importance for determination of the $D^0-{\bar{D}}^0$ mixing parameters.

Comments: 14 pages, 8 figures