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

J. H. Lacy, M. Malkan, E. E. Becklin, B. T. Soifer, G. Neugebauer, K. Matthews, C.-C. Wu, A. Boggess, T. R. Gull
1982 Astrophysical Journal  
Nearly simultaneous observations are reported of Pix, Hix, and H/J emission from 18 Seyfert galaxies and of Lyix from eight of these galaxies. In many cases, Pix is stronger relative to the Balmer lines than is predicted by recombination calculations; reddening appears to be required. Dispersion in the Pix/Hix/H/J 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 Pix/Hix
more » ... ios. High densities, large optical depths, and reddening probably all contribute to the low observed Lix/H/J ratios.
doi:10.1086/159884 fatcat:jdmhh7djprbldakgqtso7p76ky