Measurement of the difference of time-integrated CP asymmetries in $D^0\to K^{-}{K}^{+}$ and $D^0\to \ddot{I}{€}^{-}\ddot{I}{€}^{+}$ decays

Abstract

A search for CP violation in $D^0\to K^{-}{K}^{+}$ and $D^0\to \ddot{I}{€}^{-}\ddot{I}{€}^{+}$ decays is performed using $pp$ collision data, corresponding to an integrated luminosity of $3f{b}^{-1}$, collected using the LHCb detector at centre-of-mass energies of 7 and $8$TeV. The flavour of the charm meson is inferred from the charge of the pion in $D^{\ast +}\to D^0\ddot{I}{€}^{+}$ and $D^{\ast -}\to \overline{D^0}\ddot{I}{€}^{-}$ decays. The difference between the CP asymmetries in $D^0\to K^{-}{K}^{+}$ and $D^0\to \ddot{I}{€}^{-}\ddot{I}{€}^{+}$ decays, $\hat{I}”A_{CP}\equiv A_{CP}(K^{-}{K}^{+})-A_{CP}(\ddot{I}{€}^{-}\ddot{I}{€}^{+})$, is measured to be $\left(-0.10\pm 0.08(stat)\pm 0.03(syst)\right)\%$. This is the most precise measurement of a time-integrated CP asymmetry in the charm sector from a single experiment.

All figures and tables, along with any supplementary material and additional information, are available at http://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2015-055.html