Abstract
Final results from an analysis of about 400 K± → π±γγ rare decay candidates collected by the NA48/2 and NA62 experiments at CERN are presented. The results include a model-independent decay rate measurement and fits to Chiral Perturbation Theory (ChPT) description. The data support the ChPT prediction for a cusp in the di-photon invariant mass spectrum at the two pion threshold. The NA48/2 Collaboration at CERN has accumulated unprecedented statistics of rare kaon decays in the Ke4 modes K±e4 → π+π− eν and K00e4 → π0π0eν with one percent background contamination. The detailed study of the form factors brings new inputs to low energy QCD description and crucial tests of predictions from ChPT and lattice QCD calculations.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
