98.54.-h Quasars; active or peculiar galaxies, objects, and systems
- 98.54.Aj Quasars (for quasar absorption and emission-line systems; Lyman forest, see 98.62.Ra)
- 98.54.Cm Active and peculiar galaxies and related systems (including BL Lacertae objects, blazars, Seyfert galaxies, Markarian galaxies, and active galactic nuclei)
- 98.54.Ep Starburst galaxies and infrared excess galaxies
- 98.54.Gr Radio galaxies
-
98.54.Kt Protogalaxies; primordial galaxies
(1)