Revealing the Mystery Mode: Understanding the Nuclear Decay Mechanism that Governs Formation of the Universe's Heavy Elements

Executive Summary

We propose to measure the low-energy enhancement of the gamma-ray strength function using polarized photon beam and study the nature of these low-energy transitions. The combined experimental and theoretical results will improve nuclear models and constrain neutron-capture rates needed in large-scale reaction network calculations used to interpret r-process signatures from neutron star mergers.