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arXiv · 1302.2893

Charm mixing at LHCb

Angelo Di Canto
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Abstract

We report a measurement of the time-dependent ratio of $D^0\to K^+π^-$ to $D^0\to K^-π^+$ decay rates in $D^{*+}$-tagged events using 1.0\,fb$^{-1}$ of integrated luminosity recorded by the LHCb experiment. We measure the mixing parameters $x'^2=(-0.9\pm1.3)\times10^{-4}$, $y'=(7.2\pm2.4)\times10^{-3}$ and the ratio of doubly-Cabibbo-suppressed to Cabibbo-favored decay rates $R_D=(3.52\pm0.15)\times10^{-3}$. The result excludes the no-mixing hypothesis with a probability corresponding to 9.1 standard deviations and represents the first observation of charm mixing from a single measurement

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Angelo Di Canto. 2013-02-12. Charm mixing at LHCb. https://doi.org/10.1051/epjconf%2F20134913009

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