New insights into the narrow-line Seyfert 1 phenomenon

Abstract

I briefly review the X/UV absorber models and show that the observations of NLS1s are generally consistent with the models. The covering factor of absorbers in NLS1s is likely to be high and there is some evidence of super-solar metallicities. I argue that NLS1s may be active galaxies in the early stage of their evolution and as such, may be low luminosity, low redshift analogues of the high redshift quasars. NLS1s may reside in rejuvenated gas-rich galaxies. I also propose that the high Fe II emission in NLS1s may be a direct consequence of their large accretion rate and so a collisional ionization origin of Fe II is favored.