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Title: The TANAMI Multiwavelength Program: Dynamic spectral energy distributions of southern blazars

Journal Article · · Astronomy and Astrophysics
 [1];  [2];  [3];  [4];  [5];  [1];  [6];  [6];  [7];  [8];  [1];  [9];  [8];  [10];  [2];  [2];  [8];  [1];  [11];  [12] more »;  [13];  [1];  [2];  [1];  [1];  [14];  [15];  [11];  [16];  [17];  [6];  [12];  [18];  [6];  [11] « less
  1. Univ. of Erlangen-Nurnberg, Bamberg (Germany); Univ. of Wurzburg (Germany). Inst. for Theoretical Physics and Astrophysics
  2. Univ. of Erlangen-Nurnberg, Bamberg (Germany)
  3. Univ. of Wurzburg (Germany). Inst. for Theoretical Physics and Astrophysics
  4. NASA Goddard Space Flight Center (GSFC), Greenbelt, MD (United States); Univ. of Maryland Baltimore County (UMBC), Baltimore, MD (United States); The Catholic Univ. of America, Washington, DC (United States)
  5. Univ. of Erlangen-Nurnberg, Bamberg (Germany); Univ. of Wurzburg (Germany). Inst. for Theoretical Physics and Astrophysics; ASTRON, the Netherlands Institute for Radio Astronomy, Dwingeloo (Netherlands)
  6. Commonwealth Scientific and Industrial Research Organisation (CSIRO) Astronomy and Space Science, Epping (Australia)
  7. Max Planck Inst. for Radio Astronomy, Bonn (Germany); Univ. of Valencia (Spain). Dept. of Astronomy and Astrophysics and Astronomic Observatory
  8. NASA Goddard Space Flight Center (GSFC), Greenbelt, MD (United States)
  9. Univ. of Concepcion, Casilla (Chile). Dept. of Astronomy
  10. The Catholic Univ. of America, Washington, DC (United States)
  11. Auckland Univ. of Technology (New Zealand). Inst. for Radio Astronomy and Space Research
  12. Federal Agency for Cartography and Geodesy, Kotzting (Germany)
  13. Commonwealth Scientific and Industrial Research Organisation (CSIRO) Astronomy and Space Science, Tuggeranong (Australia)
  14. Univ. of Tasmania, Hobart, TAS (Australia). School of Mathematics and Physics
  15. Radboud Univ., Nijmegen (Netherlands). Dept. of Astrophysics/ IMAPP
  16. National Inst. of Astrophysics (INAF-IAPS), Rome (Italy)
  17. Nordic Optical Telescope, Santa Cruz (Spain)
  18. Hartebeesthoek Radio Astronomy, Krugersdorp (South Africa)
+ Show Author Affiliations

Simultaneous broadband spectral and temporal studies of blazars are an important tool for investigating active galactic nuclei (AGN) jet physics. Aims. Here, we study the spectral evolution between quiescent and flaring periods of 22 radio-loud AGN through multiepoch, quasi-simultaneous broadband spectra. For many of these sources these are the first broadband studies. We also use a Bayesian block analysis of Fermi/LAT light curves to determine time ranges of constant flux for constructing quasi-simultaneous spectral energy distributions (SEDs). The shapes of the resulting 81 SEDs are described by two logarithmic parabolas and a blackbody spectrum where needed. The peak frequencies and luminosities agree well with the blazar sequence for low states with higher luminosity implying lower peak frequencies. This is not true for sources in high states. The γ-ray photon index in Fermi/LAT correlates with the synchrotron peak frequency in low and intermediate states. No correlation is present in high states. The black hole mass cannot be determined from the SEDs. Surprisingly, the thermal excess often found in FSRQs at optical/UV wavelengths can be described by blackbody emission and not an accretion disk spectrum. The so-called harder-when-brighter trend, typically seen in X-ray spectra of flaring blazars, is visible in the blazar sequence. Furthermore, our results for low and intermediate states, as well as the Compton dominance, are in agreement with previous results. Black hole mass estimates using recently published parameters are in agreement with some of the more direct measurements. For two sources, estimates disagree by more than four orders of magnitude, possibly owing to boosting effects. The shapes of the thermal excess seen predominantly in flat spectrum radio quasars are inconsistent with a direct accretion disk origin.

Research Organization:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Organization:
USDOE; National Aeronautics and Space Administration (NASA); German Research Foundation (DFG)
Grant/Contract Number:
AC02-76SF00515; NNH09ZDA001N; NH10ZDA001N; NNH12ZDA001N; NNH13ZDA001N-FERMI; WI 1860-10/1
OSTI ID:
1355706
Journal Information:
Astronomy and Astrophysics, Vol. 591; ISSN 0004-6361
Publisher:
EDP SciencesCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 15 works
Citation information provided by
Web of Science

References (182)

The ultraviolet excess of Seyfert 1 galaxies and quasars journal March 1982
FERMI LARGE AREA TELESCOPE THIRD SOURCE CATALOG journal June 2015
FIRST NuSTAR OBSERVATIONS OF MRK 501 WITHIN A RADIO TO TeV MULTI-INSTRUMENT CAMPAIGN journal October 2015
From the Blazar Sequence to the Blazar Envelope: Revisiting the Relativistic jet Dichotomy in Radio-Loud Active Galactic Nuclei journal October 2011
The International Celestial Reference Frame as Realized by Very Long Baseline Interferometry journal July 1998
The 2009 December Gamma-Ray Flare of 3c 454.3: the Multifrequency Campaign journal June 2010
The connection between x-ray- and radio-selected BL Lacertae objects journal May 1995
Multi-Wavelength Observations of 3c 279 During the Extremely Bright Gamma-Ray Flare in 2014 March–April journal April 2015
A catalogue of quasars and active nuclei: 12th edition journal August 2006
Studies in Astronomical Time Series Analysis. V. Bayesian Blocks, a New Method to Analyze Structure in Photon Counting Data journal September 1998
FERMI LARGE AREA TELESCOPE DETECTION OF BRIGHT γ-RAY OUTBURSTS FROM THE PECULIAR QUASAR 4C +21.35 journal April 2011
Early Fermi Gamma-Ray Space Telescope Observations of the Quasar 3c 454.3 journal June 2009
Optical Identification of Joint EUVE and ROSAT Detections in the Southern Hemisphere: Soft Active Galactic Nuclei. journal October 1997
A new optical catalog of quasi-stellar objects journal January 1987
Atlas of quasar energy distributions journal November 1994
MULTIWAVELENGTH VARIABILITY PROPERTIES OF FERMI BLAZAR S5 0716+714 journal February 2014
The INTEGRAL mission journal November 2003
A scheme to unify low-power accreting black holes: Jet-dominated accretion flows and the radio/X-ray correlation journal January 2004
MULTI-WAVELENGTH STUDY OF FLARING ACTIVITY IN BL Lac OBJECT S5 0716+714 DURING THE 2015 OUTBURST journal August 2015
The environment of the BL Lacertae object PKS 2155-304 journal July 1993
A universal radio-X-ray correlation in low/hard state black hole binaries journal September 2003
COSMIC: Microarcsecond Resolution with a 30 Meter Radio Telescope journal April 2005
30 years of multi-wavelength observations of 3C 273 journal January 1999
CRATES: An All‐Sky Survey of Flat‐Spectrum Radio Sources
  • Healey, Stephen E.; Romani, Roger W.; Taylor, Gregory B.
  • The Astrophysical Journal Supplement Series, Vol. 171, Issue 1 https://doi.org/10.1086/513742
journal July 2007
On the Spectral Energy Distributions of Blazars journal May 1996
Multiwavelength behaviour of the blazar OJ 248 from radio to γ-rays★ journal May 2015
LEPTONIC AND HADRONIC MODELING OF FERMI -DETECTED BLAZARS journal April 2013
CGRaBS: An All‐Sky Survey of Gamma‐Ray Blazar Candidates journal March 2008
Planck 2013 results. XXVIII. The Planck Catalogue of Compact Sources journal October 2014
MULTIWAVELENGTH STUDY OF QUIESCENT STATES OF Mrk 421 WITH UNPRECEDENTED HARD X-RAY COVERAGE PROVIDED BY NuSTAR IN 2013 journal March 2016
The Rest‐Frame Extreme‐Ultraviolet Spectral Properties of Quasi‐stellar Objects journal February 2002
Roma-BZCAT: a multifrequency catalogue of blazars journal December 2008
Log-parabolic spectra and particle acceleration in the BL Lac object Mkn 421: Spectral analysis of the complete BeppoSAX wide band X-ray data set journal December 2003
Redshifts of southern radio sources journal July 1976
New blazars discovered by polarimetry journal October 1988
4.5 Years of Multi-Wavelength Observations of mrk 421 During the Argo-Ybj and Fermi Common Operation time journal January 2016
Constraining Emission Models of Luminous Blazar Sources journal September 2009
The simultaneous low state spectral energy distribution of 1ES 2344+514 from radio to very high energies journal July 2013
Using the Fundamental Plane of black hole activity to distinguish X-ray processes from weakly accreting black holes: Distinguishing black hole X-ray processes journal September 2011
SPECTRAL PROPERTIES OF BRIGHT FERMI -DETECTED BLAZARS IN THE GAMMA-RAY BAND journal January 2010
Parameter estimation in X-ray astronomy journal August 1976
The Leiden/Argentine/Bonn (LAB) Survey of Galactic HI: Final data release of the combined LDS and IAR surveys with improved stray-radiation corrections journal September 2005
Radio to gamma-ray variability study of blazar S5 0716+714 journal March 2013
Implications of the very high Energy Gamma-Ray Detection of the Quasar 3c279 journal September 2009
A high sensitivity HI survey of the sky at $\mathsf{\delta \le -25 \degr}$: Final data release journal September 2005
The European Photon Imaging Camera on XMM-Newton: The MOS cameras journal January 2001
Review of Particle Physics journal July 2012
THE JUNE 2008 FLARE OF MARKARIAN 421 FROM OPTICAL TO TeV ENERGIES journal December 2008
Comptonization of diffuse ambient radiation by a relativistic jet: The source of gamma rays from blazars? journal January 1994
Milliarcsecond-Accurate Astrometry of 34 Southern Hemisphere Radio Sources journal October 2006
A Radio Reference Frame journal August 1995
The mass fraction of AGN and the Fundamental Plane of black hole activity from a large X-ray-selected sample of LINERs journal November 2015
Photometric calibration of the Swift ultraviolet/optical telescope: Photometric calibration of the Swift UVOT journal December 2007
GAMMA-RAY LIGHT CURVES AND VARIABILITY OF BRIGHT FERMI -DETECTED BLAZARS journal September 2010
Multi-Wavelength Observations of pks 2142–75 During Active and Quiescent Gamma-Ray States journal December 2013
General physical properties of bright Fermi blazars: Properties of bright Fermi blazars journal November 2009
FERMI LARGE AREA TELESCOPE OBSERVATIONS OF MARKARIAN 421: THE MISSING PIECE OF ITS SPECTRAL ENERGY DISTRIBUTION journal July 2011
A Multiwavelength View of the TeV Blazar Markarian 421: Correlated Variability, Flaring, and Spectral Evolution journal September 2005
Radio and gamma-ray properties of extragalactic jets from the TANAMI sample journal May 2016
Optical and Near-Infrared Monitoring of the Black hole X-Ray Binary gx 339-4 During 2002-2010 journal April 2012
Free-free emission and the big blue bump in active galactic nuclei journal July 1993
The 6dF Galaxy Survey: final redshift release (DR3) and southern large-scale structures journal October 2009
THE FIRST FERMI MULTIFREQUENCY CAMPAIGN ON BL LACERTAE: CHARACTERIZING THE LOW-ACTIVITY STATE OF THE EPONYMOUS BLAZAR journal March 2011
The Swift Gamma‐Ray Burst Mission journal August 2004
A theoretical unifying scheme for gamma-ray bright blazars journal December 1998
Redshifts of southern radio sources. VI journal November 1984
The Gamma‐Ray Blazar PKS 0208−512 from MeV to GeV Energies journal November 2003
On the radio luminosity distribution of active galactic nuclei and the black hole fundamental plane journal January 2013
Total Flux Density Variations in Extragalactic Radio Sources. I. Decomposition of Variations into Exponential Flares journal January 1999
Optical spectra of southern Molonglo radio sources - I journal November 1978
Probing the Inner jet of the Quasar pks 1510–089 with Multi-Waveband Monitoring During Strong Gamma-Ray Activity journal February 2010
Compton Dominance and the Blazar Sequence journal January 2013
The Second Extension of the International Celestial Reference Frame: ICRF-EXT.1 journal June 2004
3C 279 Multiwavelength Monitoring. II. The Ground-based Campaign journal March 1996
THE SPECTRAL ENERGY DISTRIBUTION OF FERMI BRIGHT BLAZARS journal May 2010
Accretion discs in blazars journal December 2009
Simultaneous X-ray and optical observations of GX 339-4 in an X-ray high state journal September 1986
The Fermi blazars' divide journal June 2009
Unified Schemes for Radio-Loud Active Galactic Nuclei journal June 1995
The Fundamental Plane of black hole activity in the optical band journal May 2015
Smarts Optical and Infrared Monitoring of 12 Gamma-Ray Bright Blazars journal August 2012
X-ray studies of quasars with the Einstein Observatory. II journal April 1981
A Fundamental Plane of black hole activity journal November 2003
A 5 GH[CLC]z[/CLC] Southern Hemisphere VLBI Survey of Compact Radio Sources. II. journal April 1998
Erratic Flaring of bl lac in 2012–2013: Multiwavelength Observations journal January 2016
The European Photon Imaging Camera on XMM-Newton: The pn-CCD camera journal January 2001
The UV peak in active galactic nuclei: a false continuum from blurred reflection?: AGN UV peak: blurred reflection? journal May 2012
Infrared standard stars journal July 1982
THE THIRD CATALOG OF ACTIVE GALACTIC NUCLEI DETECTED BY THE FERMI LARGE AREA TELESCOPE journal August 2015
Spectral energy distributions of a large sample of BL Lacertae objects journal December 2005
A jet Model for the Broadband Spectrum of the Seyfert 1 Galaxy ngc 4051 journal June 2011
1610 - 771: A QSO with a steep optical spectrum journal September 1980
The Parkes quarter-Jansky flat-spectrum sample: I. Sample selection and source identifications journal April 2002
A self-consistent and time-dependent hybrid blazar emission model: Properties and application journal December 2014
PKS 2005-489 at VHE: four years of monitoring with HESS and simultaneous multi-wavelength observations journal February 2010
Synchrotron Self‐Compton Analysis of TeV X‐Ray‐Selected BL Lacertae Objects journal October 2008
PKS 1502+106: A NEW AND DISTANT GAMMA-RAY BLAZAR IN OUTBURST DISCOVERED BY THE FERMI LARGE AREA TELESCOPE journal January 2010
The redshift of the BL Lacertae object PKS 2005-489 journal July 1987
Evolution of BL Lacertae host galaxies journal April 2004
Discovery of VHE gamma rays from PKS 2005–489 journal May 2005
Unified Models for Active Galactic Nuclei and Quasars journal September 1993
THE 70 MONTH SWIFT -BAT ALL-SKY HARD X-RAY SURVEY journal July 2013
NuSTAR AND MULTIFREQUENCY STUDY OF THE TWO HIGH-REDSHIFT BLAZARS S5 0836+710 AND PKS 2149–306 journal July 2015
Spectroscopy of Broad-Line Blazars from 1lac journal March 2012
Is the “IR Coincidence” Just That? journal June 2005
Unveiling the nature of the γ-ray emitting active galactic nucleus PKS 0521−36 journal May 2015
The ‘harder when brighter’ X-ray behaviour of the low-luminosity active galactic nucleus NGC 7213: NGC 7213: ‘harder when brighter’ X-ray behaviour journal June 2012
Filling the infrared gap: ISO observations of 1 Jy BL Lacertae objects journal August 2006
A Composite HST Spectrum of Quasars journal February 1997
Multiwavelength Observations of a Dramatic High‐Energy Flare in the Blazar 3C 279 journal April 1998
A New System of Faint Near-Infrared Standard Stars journal November 1998
Redshifts for Southern Quasars journal October 1975
Redshifts of southern radio sources. VII journal April 1988
A unifying view of the spectral energy distributions of blazars journal September 1998
The Fundamental Plane of Accretion onto Black Holes with Dynamical Masses journal October 2009
The VLBA Calibrator Survey—VCS1 journal July 2002
CHANDRA /HETGS OBSERVATIONS OF THE BRIGHTEST FLARE SEEN FROM Sgr A* journal October 2012
Jets, black holes and disks in blazars journal January 2013
THE LARGE AREA TELESCOPE ON THE FERMI GAMMA-RAY SPACE TELESCOPE MISSION journal May 2009
X-Ray Emission from Radio-quiet Quasars in the Sloan Digital Sky Survey Early Data Release: The α[TINF][CLC]ox[/CLC][/TINF] Dependence upon Ultraviolet Luminosity journal February 2003
Continuum and line fluxes of OJ287 at minimum light journal October 1985
High-Energy Gamma-Ray Emission from Active Galaxies: EGRET Observations and Their Implications journal February 1995
[ITAL]BeppoSAX[/ITAL] Observations of Unprecedented Synchrotron Activity in the BL Lacertae Object Markarian 501 journal January 1998
TANAMI: tracking active galactic nuclei with austral milliarcsecond interferometry: I. First-epoch 8.4 GHz images journal September 2010
When Is BL Lac Not a BL Lac? journal October 1995
SIMULTANEOUS OBSERVATIONS OF PKS 2155–304 WITH HESS, FERMI , RXTE , AND ATOM: SPECTRAL ENERGY DISTRIBUTIONS AND VARIABILITY IN A LOW STATE journal April 2009
Multiwavelength observations of Mrk 501 in 2008 journal December 2014
The Two Micron All Sky Survey (2MASS) journal February 2006
Photometric studies of composite stellar systems. I - CO and JHK observations of E and S0 galaxies journal February 1978
Thermal continuum from accretion disks in quasars journal April 1978
MULTIWAVELENGTH OBSERVATIONS OF 3C 454.3. I. THE AGILE 2007 NOVEMBER CAMPAIGN ON THE “ CRAZY DIAMOND ” journal December 2008
Refining the fundamental plane of accreting black holes journal August 2006
The 6dF Galaxy Survey: samples, observational techniques and the first data release journal December 2004
The multiwavelength variability of 3C 273 journal May 2008
On the cosmological evolution of the X-ray emission from quasars journal November 1982
Long-term monitoring of PKS 0537−441 with Fermi–LAT and multiwavelength observations journal March 2013
RAPID VARIABILITY OF BLAZAR 3C 279 DURING FLARING STATES IN 2013−2014 WITH JOINT FERMI -LAT, NuSTAR , SWIFT , AND GROUND-BASED MULTI-WAVELENGTH OBSERVATIONS journal July 2015
Continuum energy distribution of quasars - Shapes and origins journal December 1989
Simultaneous Planck , Swift , and Fermi observations of X-ray and γ -ray selected blazars journal May 2012
Nanodiamond Dust and the Far‐Ultraviolet Quasar Break journal October 2005
Swift and infra-red observations of the blazar 3C 454.3 during the giant X-ray flare of May 2005 journal September 2006
Long-Term Monitoring of mrk 501 for its very high Energy γ Emission and a Flare in 2011 October journal September 2012
A simplified view of blazars: clearing the fog around long-standing selection effects: A simplified view of blazars journal February 2012
A Composite Extreme‐Ultraviolet QSO Spectrum from FUSE journal November 2004
TANAMI: Multiwavelength and multimessenger observations of active galaxies: TANAMI: Multiwavelength and multimessenger observations of active galaxies journal July 2015
Studies in Astronomical time Series Analysis. vi. Bayesian Block Representations journal February 2013
FIRST-EPOCH VLBA IMAGING OF 20 NEW TeV BLAZARS journal November 2014
Methods for Estimating Fluxes and Absorptions of Faint X-Ray Sources journal December 2009
The Wide-Field Infrared Survey Explorer (Wise): Mission Description and Initial On-Orbit Performance journal November 2010
THE FERMI LARGE AREA TELESCOPE ON ORBIT: EVENT CLASSIFICATION, INSTRUMENT RESPONSE FUNCTIONS, AND CALIBRATION journal October 2012
LOW-MASS AGNs AND THEIR RELATION TO THE FUNDAMENTAL PLANE OF BLACK HOLE ACCRETION journal May 2014
Quasars and the Big Blue Bump journal January 2005
INNOVATIONS IN THE ANALYSIS OF CHANDRA -ACIS OBSERVATIONS journal April 2010
European Southern Observatory very Large Telescope Optical Spectroscopy of bl Lacertae Objects. iii. an Extension of the Sample journal December 2008
Review of Particle Physics text January 2008
Leptonic and Hadronic Modeling of Fermi-Detected Blazars: Spectral Energy Distribution Modeling and High-Energy Polarization Predictions journal January 2013
Fermi Large Area Telescope Observations of Markarian 421: The Missing Piece of its Spectral Energy Distribution text January 2011
First NuStar Observations of MRK 501 within a Radio to TeV Multi-Instrument Campaign text January 2015
Review of Particle Physics text January 2012
CGRaBS: An All-Sky Survey of Gamma-Ray Blazar Candidates text January 2007
Synchrotron Self-Compton Analysis of TeV X-ray Selected BL Lacertae Objects text January 2008
Multiwavelength observations of 3C 454.3. I. The AGILE 2007 November campaign on the "Crazy Diamond" text January 2008
Simultaneous observations of PKS 2155-304 with H.E.S.S., Fermi, RXTE and ATOM: spectral energy distributions and variability in a low state text January 2009
Constraining Emission Models of Luminous Blazar Sources text January 2009
The Spectral Energy Distribution of Fermi bright blazars text January 2009
PKS 1502+106: a new and distant gamma-ray blazar in outburst discovered by the Fermi Large Area Telescope text January 2009
Probing the Inner Jet of the Quasar PKS 1510-089 with Multi-waveband Monitoring during Strong Gamma-ray Activity text January 2010
Gamma-ray Light Curves and Variability of Bright Fermi-Detected Blazars text January 2010
TANAMI: Tracking Active Galactic Nuclei with Austral Milliarcsecond Interferometry I. First-Epoch 8.4 GHz Images text January 2010
Fermi Large Area Telescope Detection of Bright Gamma-ray Outbursts from a Peculiar Quasar 4C +21.35 text January 2011
Simultaneous Planck, Swift, and Fermi observations of X-ray and gamma-ray selected blazars text January 2011
Optical and Near Infrared Monitoring of the Black-Hole X-ray Binary GX 339-4 During 2002-2010 text January 2012
Studies in Astronomical Time Series Analysis. VI. Bayesian Block Representations text January 2012
Chandra-HETGS Observations of the Brightest Flare Seen from Sgr A* text January 2012
Compton Dominance and the Blazar Sequence text January 2012
Leptonic and Hadronic Modeling of Fermi-Detected Blazars text January 2013
Multi-Wavelength Observations of PKS 2142-75 during Active and Quiescent Gamma-Ray States text January 2013
The Fundamental Plane of Black Hole Activity in the Optical Band text January 2015
Multi-wavelength study of flaring activity in BL Lac object S5 0716+714 during 2015 outburst text January 2015
A Scheme to Unify Low-Power Accreting Black Holes - Jet-Dominated Accretion Flows and the Radio/X-Ray Correlation text January 2003
The Leiden/Argentine/Bonn (LAB) Survey of Galactic HI: Final data release of the combined LDS and IAR surveys with improved stray-radiation corrections text January 2005
Refining the fundamental plane of accreting black holes text January 2006

Cited By (6)

Gamma-ray emission in radio galaxies under the VLBI scope: I. Parsec-scale jet kinematics and high-energy properties of journal July 2019
Breaking degeneracy in jet dynamics: multi-epoch joint modelling of the BL Lac PKS 2155–304 journal October 2018
TANAMI: Tracking Active Galactic Nuclei with Austral Milliarcsecond Interferometry: II. Additional sources journal February 2018
General Physical Properties of CGRaBS Blazars journal December 2017
Characteristic Variability Timescales in the Gamma-Ray Power Spectra of Blazars journal October 2019
On the Jet Properties of γ -Ray-loud Active Galactic Nuclei journal April 2018

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79 ASTRONOMY AND ASTROPHYSICS
galaxies: active
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quasars: general
relativistic processes