English

Chiral corrections to the Kroll-Ruderman theorem

High Energy Physics - Phenomenology 2009-10-28 v1 Nuclear Theory

Abstract

We calculate the one--loop corrections to the Kroll--Ruderman low--energy theorems for charged pion photoproduction in the framework of heavy baryon chiral perturbation theory. We predict the threshold S--wave multipole E0+E_{0+} to be E0+thr(γpπ+n)=(28.2±0.6)103/MπE_{0+}^{\rm thr}(\gamma p \to \pi^+ n) = ( 28.2 \pm 0.6 )\cdot 10^{-3}/M_{\pi} and E0+thr(γnπp)=(32.7±0.6)103/MπE_{0+}^{\rm thr} (\gamma n \to\pi^- p) = ( -32.7 \pm 0.6 )\cdot 10^{-3}/M_{\pi}, respectively, for a fixed pion--nucleon coupling constant, gπN=13.4g_{\pi N} = 13.4. A comparison to the existing data is also given.

Keywords

Cite

@article{arxiv.hep-ph/9603278,
  title  = {Chiral corrections to the Kroll-Ruderman theorem},
  author = {V. Bernard and N. Kaiser and Ulf-G. Meißner},
  journal= {arXiv preprint arXiv:hep-ph/9603278},
  year   = {2009}
}

Comments

7 pp, LaTeX