Blazar Unification through Population Synthesis
Abstract
Unification of radio-loud Active Galactic Nuclei (AGN) subtypes has long been a goal for modelers of the central black hole system, but it is difficult to evaluate competing models of blazars and other AGN using small and limited samples, as shown in the striking lack of consensus on many basic distributions and trends of interest for these models. Two efforts have been directed to provide a more robust framework for model evaluation, including (1) a thorough collection of all known blazar data into a composite sample with novel statistical methods to deal with differing biases and missing data inherent in this kind of sample, and (2) a newly developed optimization code for parametric models designed for this data. The new Fermi LAT data is instrumental in completing the blazar data set, as the inclusion of the gamma-ray spectrum allows for more accurate accounting of key observational components including bolometric luminosity, the high-energy spectral shape, and gamma-ray variability, which is utilized in the model-fitting simulation. Supplementing our large, multi-wavelength sample of over 2000 blazars compiled from every major survey, the Fermi gamma-ray data introduces necessary constraints on models by filling in the previously poorly sampled inverse compton (IC) spectrum, giving clues to the IC particle origin and tightening the radio/gamma correlation estimators. The validity of the blazar sequence is tested in this context, and is shown to be more consistent with the available data than alternate theories based on orientation or overall luminosity. Tests of various detailed physical models of blazars and AGN reveal a disparity between the observed variety of objects from that predicted by these models, and outline a course for improvement in these models.
- Publication:
-
AAS/High Energy Astrophysics Division #11
- Pub Date:
- March 2010
- Bibcode:
- 2010HEAD...11.3312M