Recent results from the NA48 experiment at CERN

The NA48/2 experiment presents a final result of the charged kaon semileptonic decays form factors measurement based on 4.28 million $K^{\pm}_{e3}$ and 2.91 million $K^{\pm}_{\mu 3}$ selected decays collected in 2004. The result is competetive with other measurements in $K^{\pm}_{\mu 3}$ mode and has a smallest uncertainty for $K^{\pm}_{e3}$, that leads to the most precise combined $K^{\pm}_{l 3}$ result and allows to reduce the form factor uncertainty of $\left | V_{US} \right |$. The NA48/2 experiment at CERN collected a very large sample of charged kaon decays into multiple final states. From this data sample we have reconstructed about 1663 events of the very rare decay $K^{\pm} \to \mu^{\pm} \nu e^{+} e^{-}$ over almost negligible background in the region with $m(e^{+}e^{−}$) above 140 MeV, which is of great interest in Chiral Perturbation Theory. We present the $m_{ee}$ spectrum and a model-independent measurement of the decay rate for this region.