Flavor decomposition of the pion-nucleon σ-term

  • Daniel SevertEmail author
  • Ulf-G. Meißner
  • Jambul Gegelia
Open Access
Regular Article - Theoretical Physics


We re-analyze the flavor decomposition of the pion-nucleon σ-term in the framework of baryon chiral perturbation to fourth order. We employ a covariant and the heavy baryon framework including also the low-lying decuplet. Using only continuum data, we find a small strangeness content of the proton. The uncertainties are, however, large and might be overcome by dedicated lattice QCD calculations.


Chiral Lagrangians Effective Field Theories 


Open Access

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Copyright information

© The Author(s) 2019

Authors and Affiliations

  • Daniel Severt
    • 1
    Email author
  • Ulf-G. Meißner
    • 1
    • 2
    • 3
  • Jambul Gegelia
    • 4
    • 3
  1. 1.Helmholtz-Institut für Strahlen- und Kernphysik and Bethe Center for Theoretical PhysicsUniversität BonnBonnGermany
  2. 2.Institute for Advanced Simulation (IAS-4) Institut für Kernphysik (IKP-3) and JCHPJülichGermany
  3. 3.Tbilisi State UniversityTbilisiGeorgia
  4. 4.Fakultät für Physik und Astronomie, Institut für Theoretische Physik IIRuhr-Universität BochumBochumGermany

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