اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدMeasurement of the $C!P$ violation parameter $A_Gamma$ in $D^0 to K^+K^-$ and $D^0 to pi^+pi^-$ decays
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Asymmetries in the time-dependent rates of $D^0 to K^+K^-$ and $D^0 to pi^+pi^-$ decays are measured in a $pp$ collision data sample collected with the LHCb detector during LHC Run 1, corresponding to an integrated luminosity of $3,mathrm{fb}^{-1}$. The asymmetries in effective decay widths between $D^0$ and $overline{D}^0$ decays, sensitive to indirect $CP$ violation, are measured to be $A_Gamma(K^+ K^-) = (-0.30 pm 0.32 pm 0.10)times 10^{-3}$ and $A_Gamma(pi^+pi^-) = (0.46 pm 0.58 pm 0.12)times 10^{-3}$, where the first uncertainty is statistical and the second systematic. These measurements show no evidence for $C!P$ violation and improve on the precision of the previous best measurements by nearly a factor of two.
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Using a data sample corresponding to 13.7 fb^-1 collected with the CLEO II and II.V detectors, we report new branching fraction measurements for two Cabibbo-suppressed decay modes of the D^+ meson: Br(D^+ to pi^+ pi^0) = (1.3 +/- 0.2) x 10^-3 and Br(
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A search for decay-time-dependent charge-parity ($CP$) asymmetry in $D^0 to K^+K^-$ and $D^0 to pi^+pi^-$ decays is performed at the LHCb experiment using proton-proton collision data recorded at a center-of-mass energy of 13TeV, and corresponding to
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Time-integrated $CP$ asymmetries in $D^0$ decays to the final states $K^- K^+$ and $pi^- pi^+$ are measured using proton-proton collisions corresponding to $3mathrm{,fb}^{-1}$ of integrated luminosity collected at centre-of-mass energies of $7mathrm{
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