Collisional cooling of primordial and interstellar media by H-2

D. R. Flower (1) , G. Pineau Des Forets (2, 3) , Pierre Hily-Blant (4) , A Faure (4) , François Lique (5) , T. Gonzalez-Lezana (6)

1 Durham University
2 IAS - Institut d'astrophysique spatiale
3 LERMA - Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique et Atmosphères = Laboratory for Studies of Radiation and Matter in Astrophysics and Atmospheres
4 IPAG - Institut de Planétologie et d'Astrophysique de Grenoble
5 IPR - Institut de Physique de Rennes
6 CSIC - Consejo Superior de Investigaciones Cientificas [España] = Spanish National Research Council [Spain]

We have computed the rate of collisional cooling of a gas by H-2 molecules under conditions appropriate to the primordial and interstellar media. We incorporated the results of recent calculations of the rate coefficients for collisional excitation of H-2 by H and H+, which arc essential to a reliable evaluation of the ortho:para H-2 ratio and the cooling rate. Comparison is made with the results of previous calculations of the cooling function. The data are made available for grids of values of the kinetic temperature, density, H:H-2 ratio, and the fractional abundance of H+, together with a programme to perform linear interpolation of the data sets for any given set of values of these parameters, within the ranges of the grids.

Mots clés: cosmology: miscellaneous; shock waves; molecular processes; molecular data; atomic data; Molecular physics; Quantum dynamics; Atomic and molecular collisions

Domaines: Physique [physics]; Astrophysique [astro-ph]

D. R. Flower, G. Pineau Des Forets, Pierre Hily-Blant, A Faure, François Lique, et al.. Collisional cooling of primordial and interstellar media by H-2. Monthly Notices of the Royal Astronomical Society, 2021, 507 (3), pp.3564-3571. ⟨10.1093/mnras/stab2272⟩. ⟨hal-03413866⟩