Year: 2025
Type: article
Abstract: We present the first benchmark measurements of oxygen opacity at high-energy-density, crucial for understanding stellar interiors. A 3-5-μm thick SiO_{2} sample was heated using a Z facility x-ray source, and opacity was measured in the 5-19.5 Å range with multiple spectrometers. The electron temperature and density inferred from Si K-shell spectra were 148±4 eV and 8.6±1.4× 10^{21} cm^{-3}, respectively. Six experiments showed opacity reproducibility within ±15% and 5%-25% opacity uncertainty. Measured oxygen opacity and seven different opacity models exhibit extraordinary overall agreement. Discrepancies near the H-like photon ionization threshold and in certain spectral lines suggest the need for model refinements.
Source: Physical Review Letters
DOI: 10.1103/n2k6-358d
Institutions: Sandia National Laboratories California, Sandia National Laboratories, The University of Texas at Austin, Lawrence Livermore National Laboratory, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, Université Paris-Saclay, CEA DAM Île-de-France, Los Alamos National Laboratory, Prism Computational Sciences (United States), University of Colorado Boulder, General Atomics (United States)
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,750
OpenAlex ID: W4416205034