Inclusive b decays to wrong sign charmed mesons

The production of wrong sign charmed mesons b → D (s)X, D (s) = (D 0, D +, D s), is studied using the data collected by the DELPHI experiment in the years 1994 and 1995. Charmed mesons in Z → bb events are exclusively reconstructed by searching for the decays D 0 → K -π +, D + → K -π +π + and D s+ φπ + → K +K -π +. The wrong sign contribution is extracted by using two discriminant variables: the charge of the b-quark at decay time, estimated from the charges of identified particles, and the momentum of the charmed meson in the rest frame of the b-hadron. The inclusive branching fractions of b-hadrons into wrong sign charm mesons are measured to be: B(b → D 0X) + B(b → D -X) = (9.3 ± 1.7(stat) ± 1.3(syst) ± 0.4(B))%, B(b → D s-X) = (10.1 ± 0.4(B))%, B(b → D s-X) = (10.1 ± 1.0(stat) ± 0.6(syst) ± 2.8(B))% where the first error is statistical, the second and third errors are systematic. © 2003 Published by Elsevier Science B.V.