CRF researchers Haw-Wei Lin, Eric Smoll, Jonathan Frank and Dave Chandler published a paper in Journal of Physics B entitled, “Absolute Cross Section Measurements via Double Resonance Ion-Imaging Mass Spectrometry: The mp51/2 n(p′/f′) Autoionizing Rydberg States of Argon.”
Employing a novel in situ double-resonance scheme using an ion-imaging mass spectrometer that can accurately measure absolute photoexcitation cross sections of excited-state atoms without the need to quantify excited-state populations directly, the researchers determined the absolute cross sections for exciting metastable Ar atoms into autoionizing Rydberg states. The team discovered that state-of-the-art ab initio calculations underestimate these specific cross sections for argon by a factor of two to three. These newly established experimental benchmarks will enable theorists to refine the treatment of many-electron correlations, core polarization potentials, and s-d mixing interactions in advanced computational models, fundamentally improving our understanding of photoexcitation.
For more details visit https://doi.org/10.1088/1361-6455/ae479c