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arXiv · hep-ph/0007095

K0 form factor at order p^6 of chiral perturbation theory

P. Post·K. Schilcher
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Abstract

This paper describes the calculation of the electromagnetic form factor of the K0 meson at order p^6 of chiral perturbation theory which is the next-to-leading order correction to the well-known p^4 result achieved by Gasser and Leutwyler. On the one hand, at order p^6 the chiral expansion contains 1- and 2-loop diagrams which are discussed in detail. Especially, a numerical procedure for calculating the irreducible 2-loop graphs of the sunset topology is presented. On the other hand, the chiral Lagrangian L^6 produces a direct coupling of the K0 current with the electromagnetic field tensor. Due to this coupling one of the unknown parameters of L^6 occurs in the contribution to the K0 charge radius.

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P. Post, K. Schilcher. 2000-10-11. K0 form factor at order p^6 of chiral perturbation theory. https://doi.org/10.1016/s0550-3213(00)00769-0

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