Measurement of the time-integrated CP asymmetry in D 0 → K {S/0} K {S/0} decays

Abstract

The time-integrated CP asymmetry in the decay D0 → K0 SK0 S is measured using 3 fb−1 of proton-proton collision data collected by the LHCb experiment at centreof-mass energies of 7 and 8 TeV. The flavour of the D0 meson is determined by use of the decay D∗+→ D0π + and its charge conjugate mode. The result is ACP = −0.029 ± 0.052 ± 0.022 , where the first uncertainty is statistical and the second systematic. The result is consistent with Standard Model expectations and improves the uncertainty with respect to the only previous measurement of this quantity by more than a factor of three.