Continuum of type 1 Seyfert galaxies. I. A single form modified by the effects of dust

Journal Article · Wed Apr 01 04:00:00 EST 1987 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/165115· OSTI ID:6269546

Ward, M; Elvis, M; Fabbiano, G; Carleton, N P; Willner, S P

Broad-band measurements from 1 to 20 microns of 26 emission-line active galactic nuclei (AGNs), mainly Seyfert 1 galaxies, have been made. These data have been combined with previous optical and infrared photometry and IRAS 12, 25, 60 and 100 micron fluxes, giving a total sample of 37 AGNs, all of which have hard X-ray measurements. The sample includes all the emission-line AGNs identified in the Piccinotti et al. (1982) survey. When corrected for stellar contributions in the near-infrared, the continuum energy distributions can be classified observationally into three types: (1) bare, minimally reddened AGNs; (2) reddened AGNs; and (3) AGNs for which the far-infrared emission is contaminated by the host galaxy. These classifications reflect a range of luminosities and different environments rather than intrinsic differences in the primary continuum of the AGNs. The data are consistent with a single underlying form of active galaxy continuum modified by the presence of dust and of the host galaxy. 77 references.

• Research Organization: Cambridge Univ., England; Washington Univ., Seattle; Harvard-Smithsonian Center for Astrophysics, Cambridge, MA
• OSTI ID: 6269546
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 315; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
COSMIC DUST
DUSTS
ELECTROMAGNETIC RADIATION
ENERGY SPECTRA
GALACTIC EVOLUTION
GALAXIES
GALAXY NUCLEI
HARD X RADIATION
IONIZING RADIATIONS
LUMINOSITY
MATHEMATICAL MODELS
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
RADIATIONS
SEYFERT GALAXIES
SPECTRA
SPECTROSCOPY
X RADIATION