Inverse-kinematics proton scattering on Ca 50: Determining effective charges using complementary probes

We have performed measurements of the 0+g.s.→2+1 excitations in the neutron-rich isotopes Ca48,50 via inelastic proton scattering on a liquid hydrogen target, using the GRETINA γ-ray tracking array. A comparison of the present results with those from previous measurements of the lifetimes of the 2+1 states provides the ratio of the neutron and proton matrix elements for the 0+g.s.→2+1 transitions. These results allow the determination of the ratio of the proton and neutron effective charges to be used in shell model calculations of neutron-rich isotopes in the vicinity of Ca48.