Revised ab initio models for H 2–H 2 collision-induced absorption at low temperatures

Abstract

A revised ab initio calculation of the H 2–H 2 collision-induced absorption results in significant differences compared with the work of J. Borysow et al. [Borysow, J., Trafton, L., Frommhold, L., Birnbaum, G., 1985. Astrophys. J. 296, 644–654] for wavenumbers greater than 600 cm −1 and temperatures below 120 K. The revision has significant influence on the spectra of Uranus and Neptune, and essentially removes the need for models with “super-solar” helium abundances or stratospheric hazes to explain the spectrum of Uranus.