Methane: the fitted model

The methane model (fit/CH4): two effective electronic oscillators fitted to the Cuthbertsons’ (1920) and Watson & Ramaswamy’s visible dispersion (level free), Achtermann’s 633 nm and Burns et al.’s 458-633 nm values, Zhao et al.’s 1566 nm value and Shelton’s N2/CH4 ratios, with HITRAN’s vibrational bands below 4500 cm^-1 fixed (reduced chi-squared 0.68; TC-797). Shown from 240 nm to 1.4 um, across the absorption gaps; the qualified intervals (240 to 1123 nm and the infrared windows) are listed in The gas models (TC-797).

from _helpers import fit_overview

fig = fit_overview("CH4", xlim=(240e-9, 1.4e-6))