Search for<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msup><mml:mi>D</mml:mi><mml:mn>0</mml:mn></mml:msup><mml:mtext mathvariant="normal">−</mml:mtext><mml:msup><mml:mover accent="true"><mml:mi>D</mml:mi><mml:mo>¯</mml:mo></mml:mover><mml:mn>0</mml:mn></mml:msup></mml:math>Mixing and Branching-Ratio Measurement in the Decay<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msup><mml:mi>D</mml:mi><mml:mn>0</mml:mn></mml:msup><mml:mo>→</mml:mo><mml:msup><mml:mi>K</mml:mi><mml:mo>+</mml:mo></mml:msup><mml:msup><mml:mi>π</mml:mi><mml:mo>−</mml:mo></mml:msup><mml:msup><mml:mi>π</mml:mi><mml:mn>0</mml:mn></mml:msup></mml:math>

We analyze $230.4\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ of data collected with the BABAR detector at the PEP-II ${e}^{+}{e}^{\ensuremath{-}}$ collider at SLAC to search for evidence of ${D}^{0}\mathrm{\text{\ensuremath{-}}}{\overline{D}}^{0}$ mixing using regions of phase space in the decay ${D}^{0}\ensuremath{\rightarrow}{K}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}{\ensuremath{\pi}}^{0}$. We measure the time-integrated mixing rate ${R}_{M}=\mathbf{(}{0.023}_{\ensuremath{-}0.014}^{+0.018}(\mathrm{stat}.)\ifmmode\pm\else\textpm\fi{}0.004(\mathrm{syst}.)\mathbf{)}%$, and ${R}_{M}<0.054%$ at the 95% confidence level, assuming $CP$ invariance. The data are consistent with no mixing at the 4.5% confidence level. We also measure the branching ratio for ${D}^{0}\ensuremath{\rightarrow}{K}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}{\ensuremath{\pi}}^{0}$ relative to ${D}^{0}\ensuremath{\rightarrow}{K}^{\ensuremath{-}}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{0}$ to be $\mathbf{(}0.214\ifmmode\pm\else\textpm\fi{}0.008(\mathrm{stat}.)\ifmmode\pm\else\textpm\fi{}0.008(\mathrm{syst}.)\mathbf{)}%$.

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.