Progress on the oxygen opacity experiments at Z

Much of our knowledge of the universe is rooted in our understanding of the Sun. However disagreement between solar models and helioseismic measurements raises concerns about the accuracy of stellar models. One hypothesis to resolve this solar problem is that the opacity at solar interior conditions is underpredicted. Past results from iron opacity experiments at the Z Machine have supported this hypothesis. Additionally, oxygen is the largest contributor to the opacity at the solar convection zone base (CZB), and it is being studied with Z experiments as well. So far, predictions of oxygen opacity at lower Te and ne (anchor 1) show outstanding overall agreement with measurements, along with some interesting indications for necessary model refinements. However, for a definitive resolution to the solar problem, benchmark experiments at higher temperatures and densities are required. Five anchor 2 experiments have been conducted, and these should provide enough data to evaluate the opacity of oxygen at conditions closer to the solar CZB. Analysis is in progress and this talk will provide a status update on this work.