NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-06-24 T03:04:24 PDT
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For refcode 1988A&A...205...53P:
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Copyright by European Southern Observatory (ESO). Reproduced by permission
1988A&A...205...53P Mass-luminosity relationships and accretion rates for Seyfert 1 galaxies and quasars P. Padovani and P. Rafanelli Dipartimento di Astronomia, Universita di Padova, Vicolo dell'Osservatorio, 5, I-35100 Padova, Italy Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 USA Received December 16, 1987; accepted April 27, 1988 Summary. We present new spectroscopic observations of a sample of 26 active galactic nuclei (AGN) obtained with the ESO 1.5 meter telescope. Adding data taken from literature, broad line region (BLR) parameters (radii and cloud velocities) and bolometric luminosities are derived for 34 Seyfert 1 galaxies and 24 low redshift quasars. Assuming infall in the inner parts of the BLR and using the relation M is proportional to v^2^r we then estimate the nuclear masses of the objects in our sample, finding that local AGN are radiating at about 1/5 of the Eddington luminosity. The dynamical mass-luminosity relationship of Seyfert 1 nuclei is similar to that of quasars, but a difference is suggested by the evaluation of the masses from the characteristic variability times and the fact that the dynamical results, obtained for Seyfert 1 galaxies, are consistent with the infall hypothesis, whilst the estimated inner radii of the BLRs of most quasars are too large for the clouds to be in infall. The mass flows through the BLR, supposing free-fall, and the accretion rates, needed in the black hole hypothesis to explain the energy outputs observed, are then calculated, showing that assuming spherical symmetry, in Seyfert 1 galaxies the two mass fluxes are roughly equal and well correlated. Taking into account the recent evidence of inflow, this result suggests that the whole BLR is falling onto the central source, providing the fuel for the AGN energy production. Quasars do not show the same correlation, but no conclusions can be drawn due to the lack of reliable determinations of the inner radii of the BLRs for AGN having z > 0.1. Key words: galaxies: active - quasars: general - mass-luminosity relationship - accretion
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