Chiral Lagrangians and Kaon CP-Violation

Abstract

These lectures are an introduction to the subject of chiral effective Lagrangians of the Standard Model and their applications, mostly in the sector of non--leptonic kaon decays, with special emphasis on CP--violation. The first lecture gives an introduction to the phenomenological description of the $K^0-{\bar{K}}^0$ system and $K\text{ra}\pi \pi$ decays. In the second lecture I give an overview of the basic ideas behind the chiral perturbation theory ($\chi$PT) --approach to hadron dynamics at low energies. The study of the weak interactions of $K$--particles within the framework of $\chi$PT is the subject of the third lecture. The fourth lecture is an overview of various models of the QCD low--energy effective action which have been developed during the last few years. The fifth lecture is dedicated to a discussion of the CP--violation $ϵ$ and ${ϵ}^{\prime }$ parameters, and to the study of the decay mode: $K_L\text{ra}{\pi }^0{e}^{+}{e}^{-}$.

Comments: 69 pages, LaTeX, Lectures given at the 1994th TASI-School on CP--Violation and the limits of the Standard Model. University of Colorado at Boulder.