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The pion-pion scattering lengths from DIRAC

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 نشر من قبل Cibran Santamarina
 تاريخ النشر 2003
  مجال البحث
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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 $pi^+ pi^-$ atom. This measurement tests the accurate predictions of the Chiral Perturbation Theory. The most recent experimental results are presented.



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