Limit on Charge Symmetry Breaking in the Optical Model and the Coulomb-Energy Anomaly

Cross sections for elastic scattering of neutrons from ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$ have been measured at 30.3 and 40.0 MeV and analyzed to obtain optical-model potentials. The optical potentials for neutron and proton scattering are found to be very similar after a correction for Coulomb effects, indicating that a static charge-symmetry-breaking Hartree potential is too small to explain the Coulomb-energy anomaly for bound states.