High resolution16O(γ*,π−p)experiment

Abstract

The reaction ${}^{16}\mathrm{O}({\ensuremath{\gamma}}^{*},{\ensuremath{\pi}}^{\ensuremath{-}}p)$ was studied with high energy resolution in the region of the \ensuremath{\Delta} resonance at the AmPS facility of NIKHEF. Photoproduction cross sections were extracted for ${1p}_{1/2}$ and ${1p}_{3/2}$ neutrons in ${}^{16}\mathrm{O}$ and the resulting pion and proton angular distributions are compared to model calculations by Lee, Wright, and Bennhold. The proton angular distributions are well described by the nonlocal version of the model and allow one to extract rms radii and spectroscopic factors for the ${1p}_{1/2}$ and ${1p}_{3/2}$ neutron shells. The same calculations are in fair agreement with the pion angular distributions.