Testing two-component models on very-high-energy gamma-ray emitting BL Lac objects

Abstract

Context. It has become evident that one-zone synchrotron self-Compton models are not always adequate for very-high-energy (VHE) gamma-ray emitting blazars. While two-component models are performing better, they are difficult to constrain due to the large number of free parameters. Aims. In this work, we make a first attempt to take into account the observational constraints from Very Long Baseline Interferometry (VLBI) data, long-term light curves (radio, optical, and X-rays) and optical polarisation to limit the parameter space for a two-component model and test if it can still reproduce the observed spectral energy distribution (SED) of the blazars. Methods. We selected five TeV BL Lac objects based on the availability of VHE gamma-ray and optical polarisation data. We collected constraints for the jet parameters from VLBI observations. We evaluated the contributions of the two components to the optical flux by means of decomposition of long-term radio and optical light curves as well as modeling of the optical polarisation variability of the objects. We selected eight epochs for these five objects, based on the variability observed at VHE gamma rays, for which we constructed the SEDs that we then modeled with a two-component model. Results. We found parameter sets which can reproduce the broadband SED of the sources in the framework of two-component models considering all available observational constraints from VLBI observations. Moreover, the constraints obtained from the long-term behavior of the sources in the lower energy bands could be used to determine the region where the emission in each band originates. Finally, we attempted to use optical polarisation data to shed new light on the behavior of the two components in the optical band. Our observationally constrained two zone model allows explanation of the entire SED from radio to VHE with two co-located emission regions.

References in corpus (92)

• Measuring Reddening with SDSS Stellar Spectra and Recalibrating SFD
• The Large Area Telescope on the Fermi Gamma-ray Space Telescope Mission
• The Leiden/Argentine/Bonn (LAB) Survey of Galactic HI: Final data release of the combined LDS and IAR surveys with improved stray-radiation corrections
• Methods and results of an automatic analysis of a complete sample of Swift-XRT observations of GRBs
• Fermi Large Area Telescope Fourth Source Catalog
• Fermi Large Area Telescope First Source Catalog
• The Spectral Energy Distribution of Fermi bright blazars
• Photometric Calibration of the Swift Ultraviolet/Optical Telescope
• Extragalactic Background Light Inferred from AEGIS Galaxy SED-type Fractions
• The Second Catalog of Active Galactic Nuclei Detected by the Fermi Large Area Telescope
• Blazars in the Fermi Era: The OVRO 40-m Telescope Monitoring Program
• The major upgrade of the MAGIC telescopes, Part II: A performance study using observations of the Crab Nebula
• Structured jets in TeV BL Lac objects and radiogalaxies
• Constraints on the Physical Parameters of TeV Blazars
• The power of blazar jets
• MOJAVE: Monitoring of Jets in AGN with VLBA Experiments. V. Multi-epoch VLBA Images
• Multiwavelength Observations of Strong Flares From the TeV-Blazar 1ES 1959+650
• The Fourth Catalog of Active Galactic Nuclei Detected by the Fermi Large Area Telescope
• MOJAVE: Monitoring of Jets in AGN with VLBA Experiments - I. First-Epoch 15 GHz Linear Polarization Images
• Generating artificial light curves: Revisited and updated
• Polarization and structure of relativistic parsec-scale AGN jets
• MOJAVE. XVII. Jet Kinematics and Parent Population Properties of Relativistically Beamed Radio-Loud Blazars
• Paper II: Calibration of the Swift ultraviolet/optical telescope
• MOJAVE XIII. Parsec-Scale AGN Jet Kinematics Analysis Based on 19 years of VLBA Observations at 15 GHz
• The Jet-Disk Connection and Blazar Unification
• Parsec Scale Properties of Markarian 501
• On the Reliability of Cross Correlation Function Lag Determinations in Active Galactic Nuclei
• Multiwaveband Polarimetric Observations of 15 Active Galactic Nuclei at High Frequencies: Correlated Polarization Behavior
• The HST Survey of BL Lacertae Objects. I. Surface Brightness Profiles, Magnitudes, and Radii of Host Galaxies
• Time-correlation between the radio and gamma-ray activity in blazars and the production site of the gamma-ray emission
• A method for the estimation of the significance of cross-correlations in unevenly sampled red-noise time series
• TeV and Multi-wavelength Observations of Mrk 421 in 2006-2008
• Host galaxy subtraction of TeV candidate BL Lacertae objects
• On the origin of the gamma-ray emission from the flaring blazar PKS 1222+216
• The Jets of TeV Blazars at Higher Resolution: 43 GHz and Polarimetric VLBA Observations from 2005-2009
• Long-term optical monitoring of TeV emitting Blazars
• The 2009 multiwavelength campaign on Mrk 421: Variability and correlation studies
• The Parsec-Scale Structure and Jet Motions of the TeV Blazars 1ES 1959+650, PKS 2155-304, and 1ES 2344+514
• Limb-Brightened Jet of 3C 84 Revealed by the 43-GHz Very-Long-Baseline-Array Observation
• Variability and stability in blazar jets on time scales of years: Optical polarization monitoring of OJ287 in 2005-2009
• Radio Jet-Ambient Medium Interactions on Parsec Scales in the Blazar 1055+018
• Measurement of the Extragalactic Background Light using MAGIC and Fermi-LAT gamma-ray observations of blazars up to z = 1
• Simultaneous multiwavelength observations of the blazar 1ES1959+650 at a low TeV flux
• On the redshift of TeV BL Lac objects
• Stochastic Acceleration in Relativistic Parallel Shocks
• Multiwavelength observations of Mkn 501 during the 1997 high state
• The Firm Redshift Lower Limit of the Most Distant TeV-Detected Blazar PKS 1424+240
• The Parsec-Scale Jets of the TeV Blazars H 1426+428, 1ES 1959+650, and PKS 2155-304: 2001-2004
• On the magnetization of BL Lac jets
• Optical polarization of high-energy BL Lac objects
• Multiband variability studies and novel broadband SED modeling of Mrk 501 in 2009
• Multiwavelength Cross-Correlations and Flaring Activity in Bright Blazars
• Are Spine--Sheath Polarization Structures in the Jets of Active Galactic Nuclei Associated with Helical Magnetic Fields?
• MAGIC long-term study of the distant TeV blazar PKS 1424+240 in a multiwavelength context
• Hard X-ray properties of NuSTAR blazars
• Multi-wavelength characterization of the blazar S5~0716+714 during an unprecedented outburst phase
• Deep Broadband Observations of the Distant Gamma-ray Blazar PKS 1424+240
• Neutrino emission in the hadronic Synchrotron Mirror Model: the "orphan" TeV flare from 1ES 1959+650
• Broadband characterisation of the very intense TeV flares of the blazar 1ES 1959+650 in 2016
• Discovery of a new TeV gamma-ray source: VER J0521+211
• Polarization swings in blazars
• The Simultaneous Low State Spectral Energy Distribution of 1ES 2344+514 from Radio to Very High Energies
• MOJAVE XVI: Multi-Epoch Linear Polarization Properties of Parsec-Scale AGN Jet Cores
• Significant Limb-Brightening in the Inner Parsec of Markarian 501
• The BL-Lac gamma-ray blazar PKS 1424+240 associated with a group of galaxies at z=0.6010
• A Fast Very High Energy $\gamma$-ray Flare from BL Lacertae during a Period of Multiwavelength activity in June 2015
• Multi-Epoch VLBA Imaging of Twenty New TeV Blazars: Apparent Jet Speeds
• VERITAS detection of $\gamma$-ray flaring activity from the BL Lac object 1ES 1727+502 during bright moonlight observations
• Hadronic-Origin orphan TeV flare from the 1ES 1959+650
• Investigating the peculiar emission from the new VHE gamma-ray source H1722+119
• Multiwavelength observations and modeling of 1ES 1959+650 in a low flux state
• Discovery of very high energy gamma-ray emission from the BL Lac object PKS 0301-243 with H.E.S.S
• Electromagnetic Catastrophe in Ultrarelativistic Shocks and the Prompt Emission of Gamma-Ray Bursts
• Optical and Radio variability of the Northern VHE gamma-ray emitting BL Lac objects
• Broadband study of blazar 1ES 1959+650 during flaring state in 2016
• Systematic Physical Characterization of the Gamma-Ray Spectra of 2FHL Blazars
• Reconciling models of luminous blazars with magnetic fluxes determined by radio core shift measurements
• An intermittent extreme BL Lac: MWL study of 1ES 2344+514 in an enhanced state
• On the origin of the soft photons of the high synchrotron peaked blazar : PKS 1424+240
• The broad-band properties of the intermediate synchrotron peaked BL Lac S2 0109+22 from radio to VHE gamma rays
• Wide band X-ray and optical observations of the BL Lac object 1ES 1959+650 in high state
• The sequence of Compton dominance in blazars based on data from WISE and Fermi/LAT
• Multiwavelength Observations of 1ES 1959+650, One Year After the Strong Outburst of 2002
• Luminous and high-frequency peaked blazars: the origin of the $\gamma$-ray emission from PKS 1424+240
• Empirical multi-wavelength prediction method for very high energy gamma-ray emitting BL Lacs
• MAGIC detection of very high energy gamma-ray emission from the low-luminosity blazar 1ES 1741+196
• Particle Acceleration and Magnetic Field Structure in PKS 2155-304: Optical Polarimetric Observations
• Polarimetric Tomography of Blazar Jets
• Probing the Transition Between the Synchrotron and Inverse-compton Spectral Components of 1ES 1959+650
• A search of CO emission lines in blazars: the low molecular gas content of BL Lac objects compared to quasars
• Multi-Wavelength Observations of the Blazar 1ES 1011+496 in Spring 2008
• Increasing the Number of TeV Blazars with Parsec-Scale Kinematics

Cited by in corpus (19)

• Science objectives of the Einstein Probe mission
• Jet collimation in NGC 315 and other nearby AGN
• Long-term multi-wavelength study of 1ES 0647+250
• A two-zone photohadronic interpretation of the EHBL-like behavior of the 2016 multi-TeV flares of 1ES 1959+650
• Interpreting the variation phenomena of B2 1633+382 via the two-component model
• Multiwavelength study of the gravitationally lensed blazar QSO B0218+357 between 2016 and 2020
• Fermi Gamma-ray Space Telescope
• First detection of VHE gamma-ray emission from TXS~1515--273, study of its X-ray variability and spectral energy distribution
• X-ray Polarization of the High-Synchrotron-Peak BL Lacertae Object 1ES 1959+650 during Intermediate and High X-ray Flux States
• Photohadronic interpretation of the different incarnation of 1ES 2344+514
• Multiple Emission Regions in Jets of Low Luminosity Active Galactic Nucleus in NGC 4278
• Very-high-energy gamma-ray detection and long-term multi-wavelength view of the flaring blazar B2 1811+31
• A spectral hardening in the Fermi-LAT Data of 1ES 0502+675
• Insights into the Long-term behavior of the optical polarization from the blazar 1ES 1959+650
• Time-dependent modelling of short-term variability in the TeV-blazar VER J0521+211 during the major flare in 2020
• Properties and Possible Physical Origins of $\gamma$-ray Emission in Extreme Synchrotron Blazars
• NuSTAR discovery of the hard X-ray emission and a wide-band X-ray spectrum from the Pictor A western hot spot
• Extreme Blazars Observed with MAGIC: Second Catalog Release
• Multiwavelength temporal and spectral study of TeV blazar 1ES 1727+502 during 2014 to 2021