Modeling nuclei of radio galaxies from VLBI radio observations. Application to the BL Lac Object S5 1803+784

Abstract

We present a new method to fit the variations of both coordinates of a VLBI component as a function of time, assuming that the nucleus of the radio source contains a binary black hole system (BBH system). The presence of a BBH system produces 2 perturbations of the trajectory of the ejected VLBI components. By using only the VLBI coordinates, the problem we have to solve reduces to an astrometric problem. Knowledge of the variations of the VLBI coordinates as a function of time contains the kinematical information, thus we are able to deduce the inclination angle of the source and the bulk Lorentz factor of the ejected component. Generally, there is a family of the BBH system producing the same fit to our data. To illustrate this method, we apply it to the source 1807+784. We find that the inclination of the source is i = 5.8+-1.8 degrees and the VLBI component is ejected with a bulk Lorentz factor of 3.7+-0.3. We determine the family of the BBH system which provides the best fit, assuming at first that the masses of the 2 black holes are equal and then that the masses are different. Each family of BBH systems is characterized by Tp/Tb~1.967, where Tp and Tb are the precession period of the accretion disk of the black hole ejecting the VLBI component and the orbiting period of the BBH system.

15 pages, 12 figures

References in corpus (7)

• Polarimetric Observations of 15 Active Galactic Nuclei at High Frequencies: Jet Kinematics from Bimonthly Monitoring with the Very Long Baseline Array
• Sub-milliarcsecond Imaging of Quasars and Active Galactic Nuclei III. Kinematics of Parsec-Scale Radio Jets
• A supermassive binary black hole in the quasar 3C345
• Sub-Milliarcsecond Imaging of Quasars and Active Galactic Nuclei. II. Additional Sources
• Monthly 43 GHz VLBA Polarimetric Monitoring of 3C120 over 16 Epochs: Evidence for Trailing Shocks in a Relativistic Jet
• Absolute kinematics of radio source components in the complete S5 polar cap sample I. First and second epoch maps at 8.4 GHz
• Absolute kinematics of radio source components in the complete S5 polar cap sample. III. First wide-field high-precision astrometry at 15.4 GHz

Cited by in corpus (18)

• A milliparsec supermassive black hole binary candidate in the galaxy SDSS J120136.02+300305.5
• A spinning supermassive black hole binary model consistent with VLBI observations of the S5 1928+738 jet
• The kinematics in the pc-scale jets of AGN The case of S5 1803+784
• Boosted Tidal Disruption by Massive Black Hole Binaries During Galaxy Mergers FROM The View of N-Body Simulation
• Photometric decomposition of mergers in disk galaxies
• Non-radial motion in the TeV blazar S5 0716+714 The pc-scale kinematics of a BL Lac Object
• Binary black holes in nuclei of extragalactic radio sources
• High-frequency very long baseline interferometry studies of NRAO 530
• A kinematic study of the compact jet in quasar B3 1633+382
• Flaring radio lanterns along the ridge line: long-term oscillatory motion in the jet of S5 1803+784
• A flat spectrum candidate for a track-type high energy neutrino emission event, the case of blazar PKS 0723-008
• Radio Crickets: Chirping Jets from Black Hole Binaries Entering their Gravitational Wave Inspiral
• Tracing the merger-driven evolution of active galaxies using the CJF sample
• Deconstructing blazars: A different scheme for jet kinematics in flat-spectrum AGN
• Multi-wavelength flare observations of the blazar S5 1803+784
• Gamma-rays in flat-spectrum AGN: Revisiting the fast jet hypothesis with the CJF sample
• Structure of the nucleus of 1928+738
• AGN jets under the microscope: A divide?