English

$\pi NN$ and $\pi N\Delta$ formfactors determined from a microscopic model for $\pi N$ scattering

Nuclear Theory 2008-11-26 v1

Abstract

We determine the πNN\pi NN and πNΔ\pi N\Delta formfactors from the P11P_{11} resp. P33P_{33} partial wave of πN\pi N scattering by dressing corresponding bare vertices with the help of πN\pi N non--pole contributions. The underlying model is based on meson exchange, and involves nucleon and delta--isobar pole and crossed--pole terms together with correlated ππ\pi\pi--exchange in the JP=0+J^P=0^+ (σ\sigma) and 11^- (ρ\rho) channel. The results are very similar for πNN\pi NN and πNΔ\pi N\Delta and can be roughly parametrized by a monopole with cutoff mass >> 500 MeV, with some variation due to model dependencies. Thus the formfactors are much less soft than derived before for the πNN\pi NN case by Saito and Afnan using the same procedure but different πN\pi N interaction models.

Keywords

Cite

@article{arxiv.nucl-th/9508021,
  title  = {$\pi NN$ and $\pi N\Delta$ formfactors determined from a microscopic model for $\pi N$ scattering},
  author = {C. Schütz and K. Holinde},
  journal= {arXiv preprint arXiv:nucl-th/9508021},
  year   = {2008}
}

Comments

7 pages, 4 postscript figures