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arXiv · 1902.02474

Isoscalar and isovector kaon form factors from $e^+e^-$ and $τ$ data

K. I. Beloborodov·V. P. Druzhinin·S. I. Serednyakov
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Abstract

The recent precise measurements of the $e^+e^-\to K_SK_L$ and $e^+e^-\to K^+K^-$ cross sections and the hadronic spectral function of the $τ^-\to K^-K_Sν_τ$ decay are used to extract the isoscalar and isovector electromagnetic kaon form factors and their relative phase in a model independent way. The experimental results are compared with a fit based on the vector-meson-dominance model.

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K. I. Beloborodov, V. P. Druzhinin, S. I. Serednyakov. 2019-04-30. Isoscalar and isovector kaon form factors from $e^+e^-$ and $τ$ data. https://doi.org/10.1134/s1063776119080016

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