NEUTRON RADII DETERMINATIONS FROM THE RATIO OF PI- ELASTIC-SCATTERING FROM C-12,C-13 AND O-16,O-18

Differential elastic cross-section ratios and absolute cross sections have been measured for C12,13 at 29.2-and 49.5-MeV average π- energy and for O16,18 at 29.2 MeV. Range telescopes detected the scattered pions. The ratio data were compared with different optical-potential calculations to extract neutron radii of 2.35 ± 0.03 fm for C13 and 2.81 ± 0.03 fm for O18, relative to the neutron radii of C12 (2.31) and O16 (2.60), respectively. Our studies indicate little sensitivity to the optical model used. © 1979 The American Physical Society.