An Accurate Measurement of the Weak Form-Factor of Lead-208

Abstract:  The PREX-2 collaboration has measured the parity-violating electroweak asymmetry in the elastic scattering of longitudinally polarized electrons from the lead-208 nucleus. This long-sought measurement determines the nuclear weak form-factor at the measurement kinematics. The result provides important constraints on the neutron skin in Pb-208 and on the density dependence of the symmetry energy in neutron-rich nuclear matter near saturation density. The interpretation of the result is precise and model independent, with a small and well-estimated theoretical uncertainty. An overview of the experimental technique and results will be presented.