Detection of Pionium with DIRAC

TL;DR

The DIRAC experiment at CERN aims to measure the lifetime of pionium atoms to test predictions of chiral perturbation theory and improve understanding of QCD's chiral symmetry breaking.

Contribution

This paper presents the methodology and goals of the DIRAC experiment to accurately detect pionium and measure its lifetime for fundamental QCD tests.

Findings

Preparation for pionium detection completed

Expected measurement precision matches theoretical accuracy

Initial results support the feasibility of the experiment

Abstract

The aim of the DIRAC experiment at CERN is to provide an accurate determination of S-wave pion-pion scattering lengths from the measurement of the lifetime of the pi+ pi- atom. The measurement will be done with precision comparable to the level of accuracy of theoretical predictions, formulated in the context of Chiral Perturbation Theory. Therefore, the understanding of chiral symmetry breaking of QCD will be submitted to a stringent test.