<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi mathvariant="normal">H</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:math>-He collisions:<i>Ab initio</i>theory meets cavity-enhanced spectra
Michał Słowiński, Franck Thibault, Yan Tan, Jin Wang, A.-W. Liu, Shui-Ming Hu, S. Kassi, A. Campargue, Magdalena Konefał, Hubert Jóźwiak, Konrad Patkowski, Piotr S. Żuchowski, R. Ciuryło, Daniel Lisak, Piotr Wcisło
Abstract
Fully quantum ab initio calculations of the collision-induced shapes of two rovibrational ${\mathrm{H}}_{2}$ lines perturbed by He provide an unprecedented subpercent agreement with ultra-accurate cavity-enhanced measurements. This level of consistency between theory and experiment hinges on a highly accurate potential energy surface and a realistic treatment of the velocity changing and dephasing collisions. In addition to the fundamental importance, these results show that ab initio calculations can provide reference data for spectroscopic studies of planet atmospheres at the required accuracy level and can be used to populate spectroscopic line-by-line databases.