Observation of the decay ψ(2S)→K∗(892)K¯+c.c.

Using 14 million ψ(2S) events collected with the BESII detector, branching fractions of ψ(2S)→K∗(892)+K−+c.c. and K∗(892)0K¯0+c.c. are determined to be: B(ψ(2S)→K∗(892)+K−+c.c.)=(2.9−1.7+1.3±0.4)×10−5 and B(ψ(2S)→K∗(892)0K¯0+c.c.)=(13.3−2.7+2.4±1.7)×10−5. The results confirm the violation of the “12% rule” for these two decay channels. A large isospin violation between the charged and neutral modes is observed.