We have observed four fully reconstructed B0 → D* + D*- candidates in 5.8×106 ϒ(4S) → BB decays recorded with the CLEO detector. The background is estimated to be 0.31±0.10 events. The probability that the background could produce four or more signal candidates with the observed distribution among D*+ and D*- decay modes is 1.1 × 10-4. The measured decay rate, B(B0 → D*+D*-) = [6.2+4.0 -2.9(stat) ± 1.0(syst)] × 10-4, is large enough for this decay mode to be of interest for the measurement of a time-dependent CP asymmetry.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)