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Measurement of angular and CP asymmetries in $D^0topi^+pi^-mu^+mu^-$ and $D^0to K^+K^-mu^+mu^-$ decays

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 نشر من قبل Angelo Di Canto
 تاريخ النشر 2018
  مجال البحث
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The first measurements of the forward-backward asymmetry of the dimuon pair ($A_{FB}$), the triple-product asymmetry ($A_{2phi}$), and the charge-parity-conjugation asymmetry ($A_{CP}$), in $D^0topi^+pi^-mu^+mu^-$ and $D^0to K^+K^-mu^+mu^-$ decays are reported. They are performed using data from proton-proton collisions collected with the LHCb experiment from 2011 to 2016, corresponding to a total integrated luminosity of 5 fb$^{-1}$. The asymmetries are measured to be begin{align*} A_{FB}(D^0topi^+pi^-mu^+mu^-) &= (phantom{-}3.3pm3.7pm0.6)%, A_{2phi}(D^0topi^+pi^-mu^+mu^-)&= (-0.6pm3.7pm0.6)%, A_{CP}(D^0topi^+pi^-mu^+mu^-) &= (phantom{-}4.9pm3.8pm0.7)%, A_{FB}(D^0to K^+K^-mu^+mu^-) &= (0pm11pm2)%, A_{2phi}(D^0to K^+K^-mu^+mu^-)&= (9pm11pm1)%, A_{CP}(D^0to K^+K^-mu^+mu^-) &= (0pm11pm2)%, end{align*} where the first uncertainty is statistical and the second systematic. The asymmetries are also measured as a function of the dimuon invariant mass. The results are consistent with the Standard Model predictions.



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