Observation of B ---> D(*) K- K0(*) decays

Abstract The B→D (∗) K − K (∗)0 decays have been observed for the first time. The branching fractions of the B→D (∗) K − K (∗)0 decay modes are measured. Significant signals are found for the B→D (∗) K − K ∗0 and B − → D 0 K − K 0 S decay modes. The invariant mass and polarization distributions for the K − K ∗0 and K − K 0 S subsystems have been studied. For the K − K ∗0 sybsystem these distributions agree well with those expected for two-body B→D (∗) a 1 − (1260) decays, with a 1 − (1260)→K − K ∗0 . The analysis was done using 29.4 fb −1 of data collected with the Belle detector at the e + e − asymmetric collider KEKB.