Effect of [formula omitted] mixing on CP asymmetries in weak decays of D and B mesons

Abstract

Within the standard electroweak model we carry out an instructive analysis of the effect of K 0 - K 0 mixing on CP asymmetries in some weak decay modes of D ± and B d O mesons. We point out that a clean signal of CP violation with magnitude of 2Re( ϵ) ≈ 3.3 × 10 −3 can manifest itself in the semileptonic decays D + → l + ν l K S ( K L ) vs D − → l − ν l K S (K L) . The CP asymmetries are also dominated by 2Re(ϵ) in the two-body nonleptonic decays D ± → ( π ±, ϱ ±, a 1 ± + ( K S , K L ) and in the multi-body processes D ± → π ± + n 0 π 0 + n ±( π ± π ∓ + ( K S , K L ), where n 0 and n ± are integers. It is possible to observe such CP-violating signals with about 10 7 D ± events at τ-charm factories or hadron machines. Finally we show that the CP asymmetry induced by Re(ϵ) may compete with those from B d 0 - B d 0 mixing and final-state interactions in the semi-inclusive and exclusive decays B d → X(c c) + (K S,K L) on the Y(4 S) resonance.