Blazar Demographics from Multiwavelength Surveys

Details Blazar Demographics from Multiwavelength Surveys Blazar Demographics from Multiwavelength Surveys

Sep 2011

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2011head...12.0730u&link_type=abstract

American Astronomical Society, HEAD meeting #12, #7.30

Astronomy and Astrophysics

Astronomy

Scientific paper

Blazars, which are characterized by relativistic jets aligned with the line of sight, are laboratories for understanding how black holes produce jets, how the jets are collimated, and how much power jets carry into the interstellar and intergalactic media. For 20 years there has been a controversy about the numbers of blazars as a function of their luminosity (or jet power). This is largely because blazars have a wide range of radio through gamma-ray spectral energy distributions (SEDs), so that selection effects strongly affect the distribution of blazars observed in any particular survey at a given wavelength. Now, the relatively large fraction of BL Lac objects in the Fermi catalog compared to the earlier EGRET catalog, which had a higher flux limit, confirms the view that low luminosity blazars are more numerous than high luminosity blazars (contrary to Giommi & Padovani papers in 1994, 1995). We show that a unifying scheme for blazars - specifically, a broad association of SED shape with luminosity - explains quantitatively the different SED types found in existing radio, X-ray, and gamma-ray blazar samples. In particular, we use simulations to produce mock samples selected at arbitrary wavelengths and flux limits, then match these to existing blazar samples. In this way we rule out the possibility that radio-luminous, EGRET-detected blazars are the dominant sub-group. Furthermore, we show that the strong negative evolution reported in X-ray-selected blazars compared to positively evolving radio-selected blazars, is caused by uneven selection (due to SED shape) from a uniformly evolving, underlying population.

Affiliated with

Also associated with

No associations

Rating

Blazar Demographics from Multiwavelength Surveys does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Blazar Demographics from Multiwavelength Surveys, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Blazar Demographics from Multiwavelength Surveys will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1402334