Search for the rare decays J/ψ→Ds−π+, J/ψ→D−π+, and J/ψ→D¯0K¯0

Rare decay modes J/ψ→Ds−π++c.c., J/ψ→D−π++c.c., and J/ψ→D¯0K¯0+c.c. are searched for using 5.77×107J/ψ events collected with the BESII detector at the BEPC. No signal above background is observed. We present upper limits on the branching fractions of B(J/ψ→Ds−π+)<1.3×10−4, B(J/ψ→D−π+)<7.5×10−5, and B(J/ψ→D¯0K¯0)<1.7×10−4 at the 90% confidence level.