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 @p) is presented using data corresponding to an integrated luminosity of 1.0 fb^-^1 collected in 2011 by LHCb in pp collisions at a centre-of-mass energy of 7 TeV. The analysis uses D^0 mesons produced in inclusive semileptonic b-hadron decays to the D^0@mX final state, where the charge of the accompanying muon is used to tag the flavour of the D^0 meson. The difference in the CP-violating asymmetries between the two decay channels is measured to be@DA_C_P=A_C_P(K^-K^+)-A_C_P(@p^-@p^+)=(0.49+/-0.30(stat)+/-0.14(syst))%. This result does not confirm the evidence for direct CP violation in the charm sector reported in other analyses.

Note:

16 pages, 5 figures. Matches the published version in PLB

CP: violation
B: semileptonic decay
p p: scattering
asymmetry: CP
particle identification: flavor
LHC-B
muon: charge
D0: hadronic decay
pi: pair production
K: pair production

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