The Blazar Sequence: Validity and Predictions

Abstract

The "blazar sequence" posits that the most powerful BL Lacertae objects and flat-spectrum radio quasars should have relatively small synchrotron peak frequencies, nu_peak, and that the least powerful such objects should have the highest nu_peak values. This would have strong implications for our understanding of jet formation and physics and the possible detection of powerful, moderately high-redshift TeV blazars. I review the validity of the blazar sequence by using the results of very recent surveys and compare its detailed predictions against observational data. I find that the blazar sequence in its simplest form is ruled out. However, powerful flat-spectrum radio quasars appear not to reach the nu_peak typical of BL Lacs. This could indeed be related to some sort of sequence, although it cannot be excluded that it is instead due to a selection effect.

9 pages, 4 figures, invited talk at the Workshop "The Multi-messenger approach to high energy gamma-ray sources", Barcelona, Spain, July 4-7, 2006, to appear in the proceedings

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Cited by in corpus (59)

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• Bright AGN Source List from the First Three Months of the Fermi Large Area Telescope All-Sky Survey
• The Fourth Catalog of Active Galactic Nuclei Detected by the Fermi Large Area Telescope
• Modeling the Emission Processes in Blazars
• A simplified view of blazars: clearing the fog around long-standing selection effects
• The blazar sequence: a new perspective
• Radio and Millimeter Continuum Surveys and their Astrophysical Implications
• The Fermi blazar sequence
• Simultaneous Planck, Swift, and Fermi observations of X-ray and gamma-ray selected blazars
• Fermi/LAT discovery of gamma-ray emission from a relativistic jet in the narrow-line quasar PMN J0948+0022
• Photopolarimetric Monitoring of Blazars in the Optical and Near-Infrared Bands with the Kanata Telescope. I. Correlations between Flux, Color, and Polarization
• Compton Dominance and the Blazar Sequence
• Planck early results. XV. Spectral energy distributions and radio continuum spectra of northern extragalactic radio sources
• The Deep X-Ray Radio Blazar Survey (DXRBS). III. Radio Number Counts, Evolutionary Properties, and Luminosity Function of Blazars
• The 3HSP catalogue of Extreme & High Synchrotron Peaked Blazars
• Multiwavelength monitoring of the enigmatic Narrow-Line Seyfert 1 PMN J0948+0022 in March-July 2009
• The Central Engines of Fermi Blazars
• Blazar sequence - an artefact of Doppler boosting
• Discovery of Very High Energy gamma-rays from the blazar S5 0716+714
• A synchrotron self-Compton scenario for the very high energy gamma-ray emission of the radiogalaxy M87
• Connection between optical and gamma-ray variability in blazars
• Mrk 421 active state in 2008: the MAGIC view, simultaneous multi-wavelength observations and SSC model constrained
• Active Galactic Nuclei under the scrutiny of CTA
• New hard-TeV extreme blazars detected with the MAGIC telescopes
• Implications on the blazar sequence and inverse Compton models from Fermi bright blazars
• Testing the blazar spectral sequence: X-ray selected blazars
• Balancing the Cosmic Energy Budget: The Cosmic X-ray Background, Blazars and the Compton Thick AGN Fraction
• Blazar nuclei in radio-loud narrow-line Seyfert 1?
• Flat-Spectrum Radio Quasars from SDSS DR3 Quasar Catalogue
• On the relationship between BL Lacertae objects and radio galaxies
• The debeamed luminosity, sychrotron peak frequency and black hole mass of BL Lac objects
• Extremes of the jet-accretion power relation of blazars, as explored by NuSTAR
• Basic properties of Fermi blazars and the "blazar sequence"
• The Spectral Shape of the Gamma-ray Background from Blazars
• A Search for Synchrotron X-ray Emission in Radio Quasars
• Incidence of MgII absorbers towards Blazars and the GRB/QSO puzzle
• High-redshift blazar identification for Swift J1656.3-3302
• Hunting extreme BL Lacertae blazars with Fermi-LAT
• Extreme & High Synchrotron Peaked Blazars at the limit of Fermi-LAT detectability: the $\gamma$-ray spectrum of 1BIGB sources
• Power for dry BL Lacertae objects
• Swift BAT, Fermi LAT, and the Blazar Sequence
• Can BL Lac emission explain the neutrinos above 0.2 PeV?
• A low density of the Extragalactic Background Light revealed by the H.E.S.S. spectra of the BLLac objects 1ES 1101-232 and H 2356-309
• Jets, black holes and disks in blazars
• Multi-Frequency Study of Spectral Indices of BL Lacertae Objects and Flat Spectrum Radio Quasars
• On leptonic models for blazars in the Fermi era
• From the Fermi blazar sequence to the relation between Fermi blazars and gamma-ray Narrow-line Seyfert 1 Galaxies
• Blazar jets launched with similar energy per baryon, independently of their power
• Radio Core-Dominance of Fermi-Blazars: Implication for Blazar Unification
• Spectral energy distributions and high-energy emission of BL Lac type objects
• Exploring the Most Extreme Gamma-Ray Blazars Using Broadband Spectral Energy Distributions
• The Spectral Sequence of Blazars - Status and Perspectives
• The radio structure of ultra-high-energy synchrotron peak BL Lacs
• Patterns of variability in gamma-ray blazars
• Monitoring the Extragalactic High Energy Sky
• Is BZB J1450+5201 the most distant $\gamma$-ray BL Lacertae object?
• The blazar sequence 2.0
• Investigating possible unification of Seyfert galaxies and blazars in Fermi-LAT sample
• The blazar sequence revised