New results on kaon decays from NA48

We report on recent results on rare and semileptonic kaon decays from NA48 and NA48/2.Using data from a minimum bias run in 1999 we present a new measurement of the CP violating decay KL→π+π− with over 40000 selected events. We measured the ratio Γ(KL→π+π−)/Γ(KL→π±e∓ν)=(4.835±0.038)×10−3 leading to the precise determination of the CP violation parameter |η+−|=(2.223±0.013)×10−3.From the same data we selected over 2×106KL→π±μ∓ν decays. Preliminary results from a dalitz plot fit yield the values for the form factors λ+=0.0260±0.0007stat±0.0010syst and λ0=0.0120±0.0008stat±0.0015syst.In one month of data taking in 2003 the NA48/2 experiment collected over 2×105K±→π±π0γ decays. A measurement of the relative contributions of Inner Bremsstrahlung, Direct Emission, and their interference is presented which results in frac(DE)=(3.35±0.35stat±0.25syst)% and frac(INT)=(−2.67±0.81stat±0.73syst)% showing for the first time a non-zero value of the interference term.