Physical Sciences and Mathematics Commons^™

Empirical Line Lists And Absorption Cross Sections For Methane At High Temperatures, R. J. Hargreaves, P. F. Bernath, J. Bailey, M. Dulick

Chemistry & Biochemistry Faculty Publications

Hot methane is found in many "cool" sub-stellar astronomical sources including brown dwarfs and exoplanets, as well as in combustion environments on Earth. We report on the first high-resolution laboratory absorption spectra of hot methane at temperatures up to 1200 K. Our observations are compared to the latest theoretical spectral predictions and recent brown dwarf spectra. The expectation that millions of weak absorption lines combine to form a continuum, not seen at room temperature, is confirmed. Our high-resolution transmittance spectra account for both the emission and absorption of methane at elevated temperatures. From these spectra, we obtain an empirical line …