Abstract
A sample of 2.8 × 104 K+ → π+μ+μ− 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 ± 0.08) × 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 \( \mathcal{O} \)(p6).
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The NA62 collaboration., Cortina Gil, E., Kleimenova, A. et al. A measurement of the K+ → π+μ+μ− decay. J. High Energ. Phys. 2022, 11 (2022). https://doi.org/10.1007/JHEP11(2022)011
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DOI: https://doi.org/10.1007/JHEP11(2022)011
Keywords
- Branching fraction
- Fixed Target Experiments
- Flavour Changing Neutral Currents
- Rare Decay