Search for direct CP violation in D⁰→h^-h⁺ modes using semileptonic B decays

A search for direct CP violation in D ⁰ →h ^-h ⁺ (where h = K or π) is presented using data corresponding to an integrated luminosity of 1.0fb ^-1 collected in 2011 by LHCb in pp collisions at a centre-of-mass energy of 7 TeV. The analysis uses D0 mesons produced in inclusive semileptonic b-hadron decays to the D ⁰μX nal state, where the charge of the accompanying muon is used to tag the avour of the D ⁰ meson. The difference in the CP-violating asymmetries between the two decay channels is measured to be ΔA _CP = A _CP(K ^-K ⁺) - ACP ( π ^-π ⁺) = ( 0.49 ±0.30 (stat)± 0.14 (syst))%. This result does not conrm the evidence for direct CP violationinthecharmsectorreportedinother analyses.