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arXiv · 1907.01566

Temperature and density dependent cooling function for H$_2$ with updated H$_2$/H collisional rates

Carla Maria Coppola·François Lique·Francesca Mazzia·Fabrizio Esposito·Mher V. Kazandjian
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Abstract

The energy transfer among the components in a gas determines its fate. Especially at low temperatures, inelastic collisions drive the cooling and the heating mechanisms. In the early Universe as well as in zero- or low- metallicity environments the major contribution comes from the collisions among atomic and molecular hydrogen, also in its deuterated version. The present work shows some updated calculations of the H$_2$ cooling function based on novel collisional data which explicitely take into account the reactive pathway at low temperatures. Deviations from previous calculations are discussed and a multivariate data analysis is performed to provide a fit depending on both the gas temperature and the density of the gas.

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Carla Maria Coppola, François Lique, Francesca Mazzia, Fabrizio Esposito, Mher V. Kazandjian. 2019-07-02. Temperature and density dependent cooling function for H$_2$ with updated H$_2$/H collisional rates. https://doi.org/10.1093/mnras%2Fstz927

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