# The K-meson form factor and charge radius: linking low-energy data to future Jefferson Laboratory measurements

The European Physical Journal C, Jul 2017

Starting from a successful model of the $\pi$-meson electromagnetic form factor, we calculate a similar form factor, $F_{K}(Q^{2})$, of the charged K meson for a wide range of the momentum transfer squared, $Q^{2}$. The only remaining free parameter is to be determined from the measurements of the K-meson charge radius, $r_{K}$. We fit this single parameter to the published data of the NA-7 experiment which measured $F_{K}(Q^{2})$ at $Q^{2}\rightarrow 0$ and determine our preferred range of $r_{K}$, which happens to be close to recent lattice results. Still, the accuracy in the determination of $r_{K}$ is poor. However, future measurements of the K-meson electromagnetic form factor at $Q^{2}\lesssim 5.5$ GeV$^{2}$, scheduled in Jefferson Laboratory for 2017, will test our approach and will reduce the uncertainty in $r_{K}$ significantly.

This is a preview of a remote PDF: https://link.springer.com/content/pdf/10.1140%2Fepjc%2Fs10052-017-5038-8.pdf

A. F. Krutov, S. V. Troitsky, V. E. Troitsky. The K-meson form factor and charge radius: linking low-energy data to future Jefferson Laboratory measurements, The European Physical Journal C, 2017, 1-8, DOI: 10.1140/epjc/s10052-017-5038-8