NOAO > Library > NOAO Preprint Series > Preprint 891
|
NOAO > Library > NOAO Preprint Series > Preprint 891 |
|
Author(s): Boroson, T.
Title: Black Hole Mass and Eddington Ratio as
Drivers for the Observable Properties
of
Radio-Loud and Radio-Quiet QSOs
Abstract:
Recent studies of black holes in the nuclei of both active and normal galaxies
have yielded relationships that permit a physical interpretation of the
principal components of the spectra of QSOs. It is shown that principal
component (or eigenvector) 1 (PC1) is driven predominantly by
L/LEdd,
and principal component 2 (PC2) is driven by accretion rate. This results in
a
PC2 vs. PC1 diagram in which lines of constant black hole mass are diagonal.
Using a sample consisting of the low-redshift PG objects supplemented by 75
radio-loud QSOs, it is shown that such a diagram effectively distinguishes
radio-loud from radio-quiet objects as well as demonstrating that both
narrow-line Seyfert 1s and broad absorption line QSOs lie at the high
L/LEdd
extreme, though these two types of objects are well separated in the PC2
direction. A simple picture that ties together physical parameters (black
hole mass and Eddington ratio) and classification of AGN is presented. Based
on
the
location of core-dominated and lobe-dominated radio-loud QSOs, orientation can
be modeled as a third parameter in this scheme, implying an enhancement in the
radio flux of core-dominated objects.
Date Received:
August 09, 2001
Publication Info:
ApJ 565:78-85
Telescopes:
None
Downloadable version (1290 Kb PDF)
|
NOAO > Library > NOAO Preprint Series > Preprint 891 |
|