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arXiv · 1403.1053

Different approaches to calculate the $K^{\pm}\to π^{\pm}π^0e^+e^-$ decay width

S. R. Gevorkyan·M. H. Misheva
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Abstract

The rare $K^\pm\toπ^\pmπ^0 e^+e^-$ decay, currently under analysis by the NA48/2 Collaboration, is considered. We have performed two theoretical approaches to calculate the differential decay width -- in the kaon rest frame, where we use Cabibbo-Maksimovicz variables, and in the center-of-mass system of the lepton pair. The latter essentially simplifies the computations. A comparison between the two approaches has been performed. We have also found the dependencies of the differential decay rate as a function of the virtual photon and dipion system masses

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S. R. Gevorkyan, M. H. Misheva. 2014-03-19. Different approaches to calculate the $K^{\pm}\to π^{\pm}π^0e^+e^-$ decay width. https://doi.org/10.1140/epjc%2Fs10052-014-2860-0

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