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arXiv · 2202.00342

Absolute measurements of state-to-state rotational energy transfer between CO and H2 at interstellar temperatures

H. Labiad·M. Fournier·L. A. Mertens·A. Faure·D. Carty·T. Stoecklin·P. Jankowski·K. Szalewicz·S. D. Le Picard·I. R. Sims
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Abstract

Experimental measurements and theoretical calculations of state-to-state rate coefficients for rotational energy transfer of CO in collision with H$_2$ are reported at the very low temperatures prevailing in dense interstellar clouds (5 - 20 K). Detailed agreement between quantum state-selected experiments performed in cold supersonic flows using time-resolved infrared - vacuum-ultraviolet double resonance spectroscopy and close-coupling quantum scattering calculations confirms the validity of the calculations for collisions between the two most abundant molecules in the interstellar medium.

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H. Labiad, M. Fournier, L. A. Mertens, A. Faure, D. Carty, T. Stoecklin, P. Jankowski, K. Szalewicz, S. D. Le Picard, I. R. Sims. 2022-02-01. Absolute measurements of state-to-state rotational energy transfer between CO and H2 at interstellar temperatures. https://doi.org/10.1103/physreva.105.l020802

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