View Full Version : Quasar Survey(s)

Kwalish Kid
2007-Feb-02, 02:04 AM
Can someone point me towards some papers/reports about quasar distribution since 1991?

Me questions were brought up about possible selection effects on observed quasar distribution in Nature in 1991, so I just want to find out what the state of quasar distribution is now.

I would also appreciate any recent info on the relation of observed quasar distribution to galaxy distribution (and gravitational lensing).

2007-Feb-02, 05:44 AM
One obvious place to go is www.2dfquasar.org (http://www.2dfquasar.org) -- the page for the 2dF Quasar Redshift Survey (23,424 quasars). There are links there to the relevant papers, as well as diagrams of the distribution of the quasars.

The SDSS (Sloan Digital Sky Survey) Quasar Catalog is another large (46,420 quasars) collection of them. If you go to the Sloan site (http://www.sdss.org/dr4/products/value_added/qsocat_dr3.html) you can find links to the papers.

There are certainly plenty of papers from SDSS (http://www.sdss.org) that deal with the galaxy distributions and gravitational lensing as well -- follow the "publications" link. Also have a look at the 2dF Galaxy Redshift Survey (http://www.mso.anu.edu.au/2dFGRS/).

2007-Feb-02, 08:22 PM
It's hard to know if there's anything better than drFish's suggestions, as your question is rather vague, Kwalish Kid.

What sort of quasar distributions are you looking for - by z? by {band} magnitude? on the sky?

Perhaps if you could say a bit more about just what sort of distribution ...?

One quite good paper, based on SDSS data, is Scranton et al (http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2005ApJ...633..589S&db_key=AST&d ata_type=HTML&format=&high=41e090e48230346): "Detection of Cosmic Magnification with the Sloan Digital Sky Survey".

Kwalish Kid
2007-Feb-02, 11:18 PM
That's pretty much what I'm looking for. If anyone can recommend good papers that are specifically about visual correlations of quasars with galaxies I'd appreciate that.

I'm following up on the Arp et al. vs. Peebles et al. Exchange that took place in Nature between 1990 and 1992. I just wanted to get a handle on the contemporary research, to see a) to what extent selection effects generated Arp's results, and b) to what extent any visual association of quasars with galaxies was explainable by relativistic effects such as lensing.

2007-Feb-02, 11:53 PM
There's a long exchange in the (ATM) Arp et al. thread on that. The Scranton et al. paper figures prominently, and (IIRC) there is a link to a BAUT (actually BABB) thread in which Scranton himself discusses the SDSS findings, wrt Arpian claims.

In a nutshell, the Arpian claims have no legs whatsoever ... (but probably best that further discussion be done in the relevant ATM thread).

Kwalish Kid
2007-Feb-03, 03:54 AM
Thanks. I coundn't tell that from the index.