New line profiles of sodium and potassium perturbed by helium for brown dwarf and very cool white dwarf stars
Résumé
The optical spectra of L- and T-type dwarfs exhibit a continuum dominated by the far wings of the absorption profiles of the Na 3s-3p and K 4s-4p doublet perturbed by molecular hydrogen and helium. We report on our work on new calculations of line profiles of Na and K perturbed by He for the conditions prevailing in brown dwarf atmospheres and very cool white dwarfs.