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arXiv · 2504.04403

Experimental observation of quantum interferences in CO-H$_2$ rotational energy transfer at room temperature

Hamza Labiad·Alexandre Faure·Ian R. Sims
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Abstract

Using time-resolved infrared-vacuum-ultraviolet double-resonance spectroscopy, experimental room temperature measurements of state-to-state rate coefficients for rotational energy transfer within the X $^1\Sigma^+(v=2)$ vibrational state of CO due to H$_2$ collisions have been compared to accurate 4-D close-coupling quantum calculations. Theoretically predicted quantum interferences in the CO-H$_2$ collisional system are experimentally observed at room temperature, and excellent agreement between theory and experiment is observed. These results provide a valuable benchmark for validating the anisotropic part of the potential energy surface, thereby supporting the theoretical modeling of CO emission in warm astrophysical environments such as photodissociation regions.

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Hamza Labiad, Alexandre Faure, Ian R. Sims. 2025-04-06. Experimental observation of quantum interferences in CO-H$_2$ rotational energy transfer at room temperature. https://doi.org/10.1103/vmq7-89ln

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