Precision measurement of n--p charge-exchange cross section at 647 MeV

The differential cross section for n--p elastic scattering in the angular region 145$sup 0$ < theta/sub c.m/ < 180$sup 0$ has been measured with high statistical accuracy using the monoenergetic neutron beam at Clinton P. Anderson Meson Physics Facility. The results differ significantly from previous Dubna and Princeton-Pennsylvania Accelerator results but agree reasonably well with recent Saclay data except at extreme backward angles. (AIP)