Left panel: VUV absorbance spectrum (120−340 nm) of frozen oxygen as deposited at 22 K (solid black curve) and after 1 keV electron irradiation at two different fluences (dashed green and solid blue lines). Right panel: VUV absorbance spectrum (120− 340 nm) of electron-irradiated frozen oxygen (22 K; solid blue line) is shown along with the spectra obtained after heating to 35 K (solid red line), 50 K (solid magenta line), and then cooling down to 22 K (dot-dashed black line). The dotted green line isa fit of the 35 K spectrum by means of Eq. (3) to highlight the Rayleigh-scattering tail in the spectrum.