High precision study of K+- --> 3pi+- decays by NA48/2

TL;DR

This paper reports precise measurements of $K^ ightarrow 3 extpi^ ightarrow$ decays, including CP violation and Dalitz plot parameters, using the NA48/2 experiment at CERN, achieving unprecedented accuracy.

Contribution

It provides the first high-precision measurements of CP violation and Dalitz plot parameters in $K^ ightarrow 3 extpi^ ightarrow$ decays with a large data set.

Findings

Measured direct CP violating charge asymmetry $A_g$ with high precision.

Determined Dalitz plot slope parameters $(g,h,k)$ accurately.

Achieved unprecedented precision due to experimental design and data volume.

Abstract

Preliminary results of study of $K^\pm\to3\pi^\pm$ decays by the NA48/2 experiment at CERN SPS are presented. They include a precise measurement of the direct CP violating charge asymmetry of Dalitz plot linear slope parameters $A_g=(g^+-g^-)/(g^++g^-)$, and a measurement of the Dalitz plot slope parameters $(g,h,k)$ themselves. Due to the design of the experiment, and a large data set collected, unprecedented precisions were achieved.