Trailed hydrogen and helium emission line spectra. Left two panels: observed line profiles of Hβ and Hγ. Center two panels: disk component obtained by subtracting the fitted spin component from the observed profiles (see text). The emission of this component stays between the two vertical dashed lines at υ_term = ±1200 km s⁻¹. Right two panels: trailed line spectra of He Iλ4471 and HeII [[INLINE178]]. These are disturbed by Mg IIλ4481 and He I λ4713 centered at +650 km s⁻¹ and +1750 km s⁻¹, respectively.