A measurement of the $K^{+}\to {\pi }^{+}{\mu }^{+}{\mu }^{-}$ decay

Abstract

A sample of $2.8\times 10^4$ $K^{+}\to {\pi }^{+}{\mu }^{+}{\mu }^{-}$ candidates with negligible background was collected by the NA62 experiment at the CERN SPS in 2017--2018. The model-independent branching fraction is measured to be $(9.15\pm 0.08)\times 10^{-8}$, a factor three more precise than previous measurements. The decay form factor is presented as a function of the squared dimuon mass. A measurement of the form factor parameters and their uncertainties is performed using a description based on Chiral Perturbation Theory at $\mathcal{O}(p^6)$.

arXiv comment17 pages, 5 figures. Updated version (6 October 2022) accepted for publication in JHEP

References in corpus (9)

• The Decays $K\to \pi {\ell }^{+}{\ell }^{-}$ beyond Leading Order in the Chiral Expansion
• The integrated low-level trigger and readout system of the CERN NA62 experiment
• Isospin Breaking in $K\to 3\pi$ Decays III: Bremsstrahlung and Fit to Experiment
• Anatomy of kaon decays and prospects for lepton flavour universality violation
• Probing lepton flavour (universality) violation at NA62 and future kaon experiments
• Soft-photon corrections in multi-body meson decays
• Radiative corrections in K --> pi l+ l- decays
• On the amplitudes for the CP-conserving $K^{\pm }(K_S)\to {\pi }^{\pm }({\pi }^0){\ell }^{+}{\ell }^{-}$ rare decay modes
• Long-distance contribution to the forward-backward asymmetry in decays K+ --> pi+ l+ l-

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