Résumé du preprint Irfu-08-361

Results from NA48/2 on pp scattering lengths measurements in K !p+p��en and K !p0p0p decays
B. Bloch-Devaux
Very large statistics of charged kaon decays have been accumulated in 2003-2004 by the NA48/2 experiment at the CERN SPS. The analyses of K !p0p0p (K3p ) and K !p+p􀀀en (Ke4) decays give complementary approaches to the study of low energy pp scattering. From data samples of 60 millions K3p and more than 1 million Ke4 decays, precise values of a0 and a2, the isospin 0 and 2 S-wave pp scattering lengths, can be extracted with an unprecedented experimental precision of few percents, allowing accurate tests of Chiral Perturbation Theory predictions. The form factors of the Ke4 decays and their energy dependence are also measured with an improved precision while the Dalitz plot parameters of the K3p decays are determined including a new quadratic term