Upper limit on the η→π+π− branching ratio with the KLOE detector

We have searched with the KLOE detector for the P and CP violating decay η→π+π− in a sample of 1.55×107η's from the decay ϕ→ηγ of ϕ-mesons produced in e+e− annihilations at DAΦNE. No signal is found. We obtain the upper limit BR(η→π+π−)<1.3×10−5 at 90% confidence level.