Measurement of partial widths and search for direct cp violation in D0 meson decays to K-K+ and π-π+

We present a measurement of relative partial widths and decay rate CP asymmetries in K-K+ and π-π+ decays of D0 mesons produced in p(bar p) collisions at √s = 1.96TeV. We use a sample of 2 x 105 D*+ → D0π+ (and charge conjugate) decays with the D0 decaying to K-π+, K-K+, and π-π+, corresponding to 123 pb-1 of data collected by the Collider Detector at Fermilab II experiment at the Fermilab Tevatron collider. No significant direct CP violation is observed. We measure Λ(D0 → K-K+)/Λ(D0 → K-π+) = 0.0992 ± 0.0011 ± 0.0012, Λ(D0 → π-π+)/Λ(D0 → K-π+) = 0.03594 ± 0.00054 ± 0.00040, ACP (K-K+) = (2.0 ± 1.2 ± 0.6)%, and ACP (π-π+) = (1.0 ± 1.3 ± 0.6) %, where, in all cases, the first uncertainty is statistical and the second is systematic