Electromagnetic effects in precision analyses of the low-energy neutron-proton interaction data

Abstract

Detailed calculations in the frame of a potential model fitted precisely to the low-energy neutron-proton (deuteron and scattering) experimental data show that the corrections introduced into measurable quantities by electromagnetic interactions are relatively as important as the hadronic contributions from nucleon isobars. The unknown behaviour of the nucleon electromagnetic form factors at high momentum transfers affects only the details of the comparison, at least when constraints provided by current quark-parton models are imposed. But the ignorance of the explicit value of the nucleon hadronic mass is found to generate, in attempts at phenomenological extraction from the data of hadronic values for the np physical quantities, uncertainties as large as the contributions from the isobar channels themselves.