Observation of B→D(*)K-K0(*) decays

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- --> (DK-KS0)-K-0 decay modes. The invariant mass and polarization distributions for the (K-K*0) and K-K-S(0) 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. (C) 2002 Elsevier Science B.V. All rights reserved.