Line profiles for the description of line mixing, narrowing, and dependence of relaxation constants on speed

Line profiles expedient for the description of the simultaneous action of line mixing, narrowing, and dependence of collision relaxation constants on molecular speed have been constructed. It is shown that negligence of the mixing of overlapped lines and speed-dependence in the case when masses of absorbing and perturbing molecules are comparable leads to systematic errors in the principal absorption line parameters in tens of percent.

► New line profile was constructed with the account of line mixing and narrowing. ► Obtained line profile ensures reliable retrieval of main line parameters. ► It is rather preferable in the case of overlapped lines. ► Neglecting mixing of overlapped lines leads to systematic errors of tens percent.