Long-distance contributions toD0−D¯0mixing parameters

Abstract

Long-distance contributions to the ${D}^{0}\mathrm{\text{\ensuremath{-}}}{\overline{D}}^{0}$ mixing parameters $x$ and $y$ are evaluated using latest data on hadronic ${D}^{0}$ decays. In particular, we take on two-body $D\ensuremath{\rightarrow}PP$ and $VP$ decays to evaluate the contributions of two-body intermediate states because they account for $\ensuremath{\sim}50%$ of hadronic ${D}^{0}$ decays. Use of the diagrammatic approach has been made to estimate yet-observed decay modes. We find that $y$ is of order a few $\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}3}$ and $x$ of order ${10}^{\ensuremath{-}3}$ from hadronic $PP$ and $VP$ modes. These are in good agreement with the latest direct measurement of ${D}^{0}\mathrm{\text{\ensuremath{-}}}{\overline{D}}^{0}$ mixing parameters using the ${D}^{0}\ensuremath{\rightarrow}{K}_{S}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ and ${K}_{S}{K}^{+}{K}^{\ensuremath{-}}$ decays by BABAR. We estimate the contribution to $y$ from the $VV$ modes using the factorization model and comment on the single-particle resonance effects and contributions from other two-body modes involving even-parity states.