Modeling of pressure-induced far-infrared absorption spectra: Molecular hydrogen pairs

Journal Article · Sun Sep 15 04:00:00 EDT 1985 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/163482· OSTI ID:6174772

Borysow, J; Trafton, L; Frommhold, L; Birnbaum, G

The collision-induced translational-rotational absorption coefficient for molecular hydrogen pairs has been computed from the fundamental theory by Meyer, Frommhold, and Birnbaum for temperatures from 40 to 300 K. Over the frequency range from approx.30 to 1500 cm , theoretical and measured profiles are in close agreement (+-5%). The theory is capable of generating reliable spectra of hydrogen pairs at temperatures for which no laboratory measurements exist. Since quantum line shape computations cannot be readily repeated elsewhere on account of their complexity, we identify simple, suitable functions which approximate the exact profiles closely (approx.1%), even in the far wings. The absorption spectra are well reproduced by simple three-parameters are determined by least-squares fits of the theoretical profiles. They vary smoothly with temperature T. The collision-induced translational-rotational absorption coefficient, ( ), of H2-H2 can thus be reliably and very rapidly reproduced on computers of small capacity, using codes with simple programming. This facilitates accurate computations of radiative transfer in modeling the atmospheres of the outer planets.

• Research Organization: University of Texas at Austin
• OSTI ID: 6174772
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 296:2; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640302* -- Atomic
Molecular & Chemical Physics-- Atomic & Molecular Properties & Theory
74 ATOMIC AND MOLECULAR PHYSICS
ABSORPTION SPECTRA
ATMOSPHERES
COLLISIONS
ELECTROMAGNETIC RADIATION
ELEMENTS
ENERGY LEVELS
EXCITED STATES
FAR INFRARED RADIATION
FUNCTIONS
HYDROGEN
INFRARED RADIATION
MECHANICS
MOLECULE COLLISIONS
MOLECULES
NONMETALS
PLANETARY ATMOSPHERES
QUANTUM MECHANICS
RADIATIONS
ROTATIONAL STATES
SPECTRA
SPECTRAL FUNCTIONS