The NA48/2 Collaboration at CERN has accumulated and analysed unprecedented
statistics of rare kaon decays in the Ke4​ modes: Ke4​(+−) (K±→π+π−e±ν) and Ke4​(00) (K±→π0π0e±ν)
with nearly one percent background contamination. It leads to the improved
measurement of branching fractions and detailed form factor studies. New final
results from the analysis of 381 K±→π±γγ rare decay
candidates collected by the NA48/2 and NA62 experiments at CERN are presented.
The results include a decay rate measurement and fits to Chiral Perturbation
Theory (ChPT) description.Comment: Prepared for the Proceedings of "Moriond QCD and High Energy
Interactions. March 22-29 2014." conferenc