Misc,
A Walk-Through of AGN Country -- for the somewhat initiated!
(2023)cite arxiv:2308.04621Comment: 24 pages, 6 figures.
Abstract
Some key issues in AGN and galaxy formation are discussed. Very successful
Unified Models explain much of the variety of AGN with orientation effects;
ingredients are shadowing by a dusty "torus" and relativistic beaming. A
spinoff result is described which is important for the formation of massive
elliptical galaxies. It's the most spectacular and unequivocal AGN feedback
phenomenon known. This is the so-called älignment effect" in powerful radio
galaxies at z>~1. One of them is a BAL radio galaxy! I explain a very robust
derivation of the reddening law for nuclear dust, which reveals a dearth of
small grains. Then the quasistatic thin accretion disk model, thought by many
to explain the energetically dominant optical/UV continuum, is thoroughly
debunked. Much of this was known when the model was proposed 35 years ago. A
new argument is given that trivially falsifies a huge superset of such models.
It's possible to see the central engine spectrum with the atomic and dust
emission surgically removed! Few noticed this breakthrough work. The far IR
dust emission in Cygnus A is 10% polarized, and so far high nuclear dust
polarization is seen in all radio loud objects, but no radio quiet ones.
