A Parametrization for $K^{+}\to {\pi }^{+}{\pi }^{-}{e}^{+}\nu$

Abstract

We discuss various models and Chiral Perturbation Theory results for the $K_{l4}$ form factors $F$ and $G$. We check in how much a simple parametrization with a few parameters can be used to extract information from experiment.

19 pages, 14 figures