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The pion-pion scattering lengths from DIRAC

Cibran Santamarina
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Abstract

The scattering lengths of a two pion system are the {\it golden magnitudes} to test the QCD predictions in the low energy sector. The DIRAC (PS-212) experiment at CERN will obtain a particular combination of the S-wave isospin 0 and 2 scattering lengths by measuring the lifetime of pionium, the hydrogen-like $π^+ π^-$ atom. This measurement tests the accurate predictions of the Chiral Perturbation Theory. The most recent experimental results are presented.

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Cibran Santamarina. 2003-09-30. The pion-pion scattering lengths from DIRAC. https://doi.org/10.1063/1.1799699

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