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Johan Bijnens in front of his whiteboard

Johan Bijnens

Professor, Deputy Head of Division

Johan Bijnens in front of his whiteboard

Pion-pion scattering at low energy

Author

  • J. Bijnens
  • G. Colangelo
  • G. Ecker
  • J. Gasser
  • M. E. Sainio

Summary, in English

We present technical details of the evaluation of the elastic ππ scattering amplitude to two loops in chiral perturbation theory. In particular, we elaborate on the renormalization procedure at the two-loop order and on the evaluation of the relevant Feynman diagrams that can all be expressed in terms of elementary functions. For the sake of clarity, we discuss these matters both in the N-component φ4 theory (in its symmetric phase) and in chiral perturbation theory. Estimates for the relevant low-energy constants of O(p6) are presented. Threshold parameters and phase shifts are then calculated for two sets of O(p4) coupling constants and compared with experiment. We comment on the extraction of threshold parameters from phase shift data.

Department/s

  • Theoretical Particle Physics - Has been reorganised

Publishing year

1997-12-22

Language

English

Pages

263-310

Publication/Series

Nuclear Physics B

Volume

508

Issue

1-2

Document type

Journal article

Publisher

North-Holland

Topic

  • Other Physics Topics

Keywords

  • Chiral perturbation theory
  • Chiral symmetry
  • Pion-pion scattering

Status

Published

ISBN/ISSN/Other

  • ISSN: 0550-3213