Speaker
Description
The density dependence of the symmetry energy is a quantity that has long been anticipated to inform the determination of the neutron matter equation of state (EOS). Knowledge of the neutron distribution in heavy nuclei impacts nuclear structure theory, our understanding of neutron star structure, nuclear spectroscopy, atomic parity measurements and more. Electron scattering has already proven to be powerful tool for determining the sizes of nuclei by measuring the electric charge distribution. It provides a clean probe of the nucleus that does not interact via the strong force. Parity-violating electron scattering (PVES) is a technique that exploits the fact that the weak force violates parity while the electromagnetic force is parity-conserving. In order to form the parity-violating asymmetry that allows us to isolate the weak term in the scattering cross-section, we employ a longitudinally polarized electron beam, with rapidly flipping helicity. The state-of-the-art Thomas Jefferson National Accelerator Facility in Newport News, Virginia, USA is able to produce the required highly polarized, high current, stable electron beam to perform such measurements. In this talk I will give an overview of the recently completed PREX and CREX experiments, present the results, and discuss some of the implications of the measurements.
