Status of the measurement ofKS→πeνbranching ratio and lepton charge asymmetry with the KLOE detector

Daria Kamińska

doi:10.1051/epjconf/20148102007

Abstract

We present the current status of the analysis of about 1.7 billion KS KL pair events collected at DAΦNE with the KLOE detector to determine the branching ratio of KS → πeν decay and the lepton charge asymmetry. This sample is ∼ 4 times larger in statistics than the one used in the previous most precise result, from KLOE as well, allow- ing us to improve the accuracy on the measurement and related tests of CPT symmetry and ΔS =Δ Q rule.

Highlights

The CPT symmetry assumes invariance of physical laws under the combination of the symmetries such as charge conjugation (C), parity (P) and time reversal (T )
One of possible ways to test violation of CPT symmetry and basic assumptions of the Standard Model in the neutral kaon system is based on the difference between charge asymmetries for short-lived kaon (AS ) and for long-lived kaon (AL)
Symmetry, the value of AL [1] was determined with a precision more than two orders of magnitude better than AS [2]

Summary

Introduction

The CPT symmetry assumes invariance of physical laws under the combination of the symmetries such as charge conjugation (C), parity (P) and time reversal (T ). One of possible ways to test violation of CPT symmetry and basic assumptions of the Standard Model in the neutral kaon system is based on the difference between charge asymmetries for short-lived kaon (AS ) and for long-lived kaon (AL). ¡¡ Presently this difference is compatible with zero within errors, which suggests conservation of CPT

Results

Conclusion