Constraining Evolution of Magnetic Field Strength in Dissipation Region of Two BL Lac Objects

Abstract

With the assumption that the optical variability timescale is dominated by the cooling time of the synchrotron process for BL Lac objects, we estimate time dependent magnetic field strength of the emission region for two BL Lac objects. The average magnetic field strengths are consistent with those estimated from core shift measurement and spectral energy distribution modelling. Variation of magnetic field strength in dissipation region is discovered. Variability of flux and magnetic field strength show no clear correlation, which indicates the variation of magnetic field is not the dominant reason of variability origin. The evolution of magnetic field strength can provide another approach to constrain the energy dissipation mechanism in jet.

9 pages, 2 figures

References in corpus (17)

• Relativistic Jets Shine through Shocks or Magnetic Reconnection?
• MOJAVE: Monitoring of Jets in Active Galactic Nuclei with VLBA Experiments. VIII. Faraday rotation in parsec-scale AGN jets
• Multi-colour optical monitoring of eight red blazars
• Multifrequency monitoring of the blazar 0716+714 during the GASP-WEBT-AGILE campaign of 2007
• Optical Intra-day Variability in Blazars
• Leptonic and Hadronic Radiative Processes in Supermassive-Black-Hole Jets
• Testing the inverse-Compton catastrophe scenario in the intra-day variable blazar S5 0716+71. I. Simultaneous broadband observations during November 2003
• Multifrequency Photo-polarimetric WEBT Observation Campaign on the Blazar S5 0716+714: Source Microvariability and Search for Characteristic Timescales
• The dual nature of blazar fast variability. Space and ground observations of S5 0716+714
• Frequency and Time Dependence of Linear Polarization in Turbulent Jets of Blazars
• Analytical Solution of Magnetically Dominated Astrophysical Jets and Winds: Jet Launching, Acceleration, and Collimation
• Rapid optical variability in blazar S5 0716+71 during 2010 March
• Reconciling models of luminous blazars with magnetic fluxes determined by radio core shift measurements
• Constraints on the location of $\gamma$-ray emitting region for a sample of blazars with radio core-shift measurements
• A bias in VLBI measurements of the core shift effect in AGN jets
• A numerical study of long-term multi-wavelength blazar variability
• On the Origin and Evolution of Curvature of the Spectral Energy Distribution of Fermi Bright Blazars