ScienceProblem: ActiveGalaxiesUnbiasedStudy




To try and understand active galaxies


Multi-wavelength surveys and well-defined catalogues of the properties of AGN


Though there is a wealth of high quality information on AGN, significant progress in our understanding has not advanced much since basic unified schemes were invented more than a decade ago. The barrier to better exploitation of the data is the interplay between complex selection effects and the astrophysics. How to we cut through the selection and get at the astrophysics.


Judging by the literature, there are no available solutions!


There are two aspects to the solution:

1. The astronomer needs software to build a "virtual universe" by populating with sets of objects according to standard rules, for example, a cosmological model, luminosity functions, cosmological evolution, random orientation wrt to the observer, etc. In addition each object needs to be assigned a distribution of physical properties based on a best-guess astrophysical physical model. Having populated the virtual universe, it then needs to be sampled (observed) using the same selection functions as the observations available via the grid.)

2. The grid needs to make available catalogues of objects and their properties with their respective selection parameters. It is important to emphasize that, without the latter, the data are pretty useless.

The astrophysics comes from the comparison of the real universe sampling and the virtual universe sampling. How the loop is closed to evolve the parameters in the virtual universe to match the real on is sampling and the virtual universe sampling. How the loop is closed to evolve the parameters in the virtual universe to match the real on is another question. A simple application of this approach that has already been used is the analysis of radio source luminosity functions by Jackson & Wall (1999). Their model inputs were a relativistic beaming unified schemes.


Jackson, C. A. & Wall, J. V. 1999, Monthly Notices of the Royal Astronomical Society, Volume 304, Issue 1, pp. 160-174. Extragalactic radio-source evolution under the dual-population unification scheme

Blundell, Katherine M., Rawlings, Steve, & Willott, Chris J. 1999, The Astronomical Journal, Volume 117, Issue 2, pp. 677-706. The Nature and Evolution of Classical Double Radio Sources from Complete Samples

GoodStyle: Please add comments below. This area should be used for refinement of the above document. If you want to ask questions or start a dialogue with the author, please use (or create) a topic in the Science Problems Forum. For other ScienceProblems, refer to the ScienceProblemList.
Author: Once the refinements here and comments in the forum die down, perhaps you could rewrite the problem, incorporating the comments and refinements.

This case is of general nature and as such is beyond the scope of the three year AstroGrid remit. A subset problem needs to be generated from this case - preferably making use of data resources available to AstroGrid in the next 3-4 years.

-- NicholasWalton - 17 Apr 2002

-- Ian Browne and AnitaRichards - 01 Feb 2002

Topic revision: r7 - 2002-05-30 - 14:41:55 - NicholasWalton
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