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arXiv · 1012.2415

CP violation in the D0 -> pi+ pi- decay at CDF

Michael Joseph Morello
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Abstract

We report a measurement of the \CP\ violating asymmetry in $D^0\toπ^+π^-$ decays using approximately 215,000 decays reconstructed in about $5.94$ fb$^{-1}$ of CDF data. We use the strong $D^{\star +}\to D^0π^+$ decay ("$D^{\star}$ tag") to identify the flavor of the charmed meson at production time and exploit \CP-conserving strong $c\bar{c}$ pair-production in $p\bar{p}$ collisions. Higher statistic samples of Cabibbo-favored $D^0\to K^-π^+$ decays with and without $D^{\star}$ tag are used to highly suppress systematic uncertainties due to detector effects. The result, $\Acp(D^0 \to π^{+}π^{-}) = \bigl[0.22\pm0.24\stat\pm0.11\syst\bigr]%$, is the world's most precise measurement to date and it is fully consistent with no \CP\ violation.

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Michael Joseph Morello. 2010-12-11. CP violation in the D0 -> pi+ pi- decay at CDF. https://doi.org/10.1142/s2010194511000699

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