اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدMeasurement of $y_{CP}$ in $D^0-overline{D}^0$ oscillation using quantum correlations in $e^+e^-to D^0overline{D}^0$ at $sqrt{s}$ = 3.773,GeV
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We report a measurement of the parameter $y_{CP}$ in $ensuremath{D^0}xspace-ensuremath{overline{D}^{0}}xspace$ oscillations performed by taking advantage of quantum coherence between pairs of $ensuremath{D^0}xspace ensuremath{overline{D}^{0}}xspace$ mesons produced in $e^+e^-$ annihilations near threshold. In this work, doubly-tagged $ensuremath{D^0}xspace ensuremath{overline{D}^{0}}xspace$ events, where one $D$ decays to a $CP$ eigenstate and the other $D$ decays in a semileptonic mode, are reconstructed using a data sample of 2.92,fb$^{-1}$ collected with the BESIII detector at the center-of-mass energy of $sqrt{s}$ = 3.773,GeV. We obtain $y_{CP} = (-2.0pm1.3pm0.7)%$, where the first uncertainty is statistical and the second is systematic. This result is compatible with the current world average.
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