Observation of B0→χc0K*0 and evidence for B+→χc0K*+

We present the observation of the decay B0→χc0K*0 as well as evidence of B+→χc0K*+, with an 8.9 and a 3.6 standard deviation significance, respectively, using a data sample of 454×106 Υ(4S)→BB̅ decays collected with the BABAR detector at the PEP-II B meson factory located at the Stanford Linear Accelerator Center (SLAC). The measured branching fractions are B(B0→χc0K*0)=(1.7±0.3±0.2)×10-4 and B(B+→χc0K*+)=(1.4±0.5±0.2)×10-4, where the first quoted errors are statistical and the second are systematic. We obtain a branching fraction upper limit of B(B+→χc0K*+)<2.1×10-4 at the 90% confidence level.