*sigh* Here we go again. I can't put together a full reply as I need to walk the dog and eat dinner, but I'll just make a few comments (of course, that usually means I'll spend much
way too much time on this... oh-well).
Quote:
Originally Posted by rtomes
I do not intend to get into what the definition of a quasar is, leaving that entirely to the astronomers. It is not relevant to the arguments offered here. Now to those arguments, and a new proposal that I shall put forward.
|
As I've mentioned to you several times before, this is your first problem. "What a quasar is observationally" is absolutely relevant to the discussion: different selection techniques can overlap by less than 20%.
And here's something that should make you think a little bit: the difference between a "quasar" and an "active galaxy" in many catalogs is based on an absolute magnitude cut. Do you know what that means?
I really should try to finish that Quasar thread... If it'll be read...
As to the plot that you showed from "Associations between Quasi-stellar Objects and Galaxies", do you know how much more we understand about AGN since 1990, and how many more objects there are? Selection and identification of quasars prior to ~2000 was generally very haphazard, so I would put very little trust in such plots from before that time.
Quote:
Originally Posted by rtomes
In addition I propose a new test that will make this even clearer. The new test is to look at samples of quasars and galaxies that have very different redshifts (say > .01) and are very nearby in the sky (specifically that they are unlikely to be chance associations by statistical arguments) and to test the two models by the following procedure.
|
How will you select quasasrs that are "unlikely to be chance associations by statistical arguments?" The (optically selected, broad-line) quasar density on the sky is
~10 per square degree to i=19.1. That's quite a lot. It means one would expect >100 (optically selected, broad-line) quasars in the vicinity of, say, Andromeda (though M31 isn't part of the main SDSS survey, I hope you get my point).
Also notice the very important: optically selected, broad-line. Radio, X-ray and IR selection find different objects, and give somewhat different densities.
So, how you gonna pick 'em?