English

Virtual photons to fourth order CHPT with nucleons

High Energy Physics - Phenomenology 2011-04-15 v1

Abstract

I discuss the whole mechanism to calculate isospin violation effects in the framework of CHPT. In order to get the correct size of isospin violation one has to include all non-isospin symmetric sources like the electromagnetic interaction, the quark mass difference (π0η\pi_0 - \eta mixing), explicit photon loops. As examples I discuss the electromagnetic contributions to the pion nucleon sigma term and to the S-wave pion nucleon scattering length.

Keywords

Cite

@article{arxiv.hep-ph/9908470,
  title  = {Virtual photons to fourth order CHPT with nucleons},
  author = {Guido Mueller},
  journal= {arXiv preprint arXiv:hep-ph/9908470},
  year   = {2011}
}

Comments

5 pages, talk given at MENU99, 18th International Symposium on Meson-Nucleon Physics and the Structure of the Nucleon, Zuoz, August 15-21,1999

R2 v1 2026-07-22T14:53:23.477Z