Temperature and density dependent cooling function for H2 with updated H2/H collisional rates

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. This work shows some updated calculations of the H2 cooling function based on novel collisional data which explicitly 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.