Continuum-subtracted CO(2–1) emission line profile for 23 Seyfert 2 galaxies observed by APEX. Fluxes are expressed as antenna temperatures (, in units of mK), and the spectral axis is in velocity units (km s⁻¹), calculated with respect to the expected CO(2–1) sky frequency at the redshift of each source, assuming the radio conversion for the velocity. Each panel spans a fixed range of 2000 km s⁻¹ in velocity around the systemic velocity of the galaxy to allow a simple visual comparison of the kinematics of the lines. The CO(2–1) emission is clearly detected in all observations, with at least S/N = 4 in the channel corresponding to the peak of the line profile. The dashed green line represents the best-fit function, which consists of one or two Gaussian functions, depending on the spectral line profile; the solid red line represents the zero K level.