https://doi.org/10.1051/epjconf/20148103005
ChPT tests at NA48 and NA62
Laboratori Nazionali di Frascati - INFN, Via E. Fermi, 40 - 00044 Frascati (Rome), Italy
a e-mail: francesco.gonnella@lnf.infn.it
b The NA48/2 Collaboration: Cambridge, CERN, Dubna, Chicago, Edinburgh, Ferrara, Firenze, Mainz, Northwestern, Perugia, Pisa, Saclay, Siegen, Torino, Wien.
c The NA62-RK Collaboration: Birmingham, CERN, Dubna, Fairfax, Ferrara, Firenze, Frascati, Mainz, Merced, Moscow, Napoli, Perugia, Pisa, Protvino, Roma I, Roma II, Saclay, San Luis Potosi, Stanford, Sofia, Torino,TRIUMF
Published online: 26 November 2014
Final results from an analysis of about 400 K± → π±γγ rare decay candidates collected by the NA48/2 and NA62 experiments at CERN during low intensity runs with minimum bias trigger configurations 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.
© Owned by the authors, published by EDP Sciences, 2014
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