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Nearly simultaneous observations are reported of Pɑ, Hɑ, and Hβ emission from 18 Seyfert galaxies and of Lyɑ from eight of these galaxies. In many cases, Pɑ is stronger relative to the Balmer lines than is predicted by recombination calculations; reddening appears to be required. Dispersion in the Pɑ/Hɑ/Hβ ratios orthogonal to the reddening track indicates that high densities or optical depths also affect the line flux ratios. Several galaxies, notably NGC 1275, have very low Pɑ/Hɑ ratios. High densities, large optical depths, and reddening probably all contribute to the low observed Lɑ/Hβ ratios.

Infrared, optical, and ultraviolet observations of hydrogen line emission from Seyfert galaxies