2002/01/05 by Aaron J. Barth, A. J. Barth, Barth, A. J.
Engineering · Physics and Astronomy · #Advanced Optical Sensing Technologies #Astrophysics (astro-ph) #CCD and CMOS Imaging Sensors #FOS: Physical sciences #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/0201065
To appear in "Issues in Unification of AGNs", edited by R. Maiolino, A. Marconi, & N.Nagar (ASP Conference Series, in press). 12 pages
arxiv created 2002/01/05 · openalex publication_date 2002/01/05 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
More than one third of all nearby galaxies show indications of low-luminosity nuclear activity. These low-luminosity AGNs (LLAGNs) are traditionally classified into a variety of categories depending on their forbidden-line ratios and on the presence or absence of broad-line emission. By analogy with Seyfert unification models, it is natural to ask whether the various LLAGN types are different manifestations of the same underlying phenomenon, with observed differences being solely due to orientation and obscuration, or whether there are fundamentally distinct physical processes at work in different categories of LLAGNs. This contribution reviews some recent observations of LLAGNs in the context of AGN unification scenarios.