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Evaluation of the Pion-Nucleon Sigma Term from CHAOS Data

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 نشر من قبل Heinz A. Clement
 تاريخ النشر 2012
  مجال البحث
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We have reanalyzed the $pi ^{pm} p$ scattering data at low energy in the Coulomb-nuclear interference region as measured by the CHAOS group at TRIUMF with the aim to determine the pion-nucleon $sigma$ term. The resulting value $sigma=(44pm 12)$ MeV, while in agreement with lattice QCD calculations and compatible with other recent analyses, is significantly lower than that from the GWU-TRIUMF analysis of 2002.



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