Probing the innermost regions of AGN jets and their magnetic fields with RadioAstron. V. Space and ground millimeter-VLBI imaging of OJ 287

Abstract

We present the first polarimetric space VLBI observations of OJ 287, observed with RadioAstron at 22 GHz during a perigee session on 2014 April 4 and five near-in-time snapshots, together with contemporaneous ground VLBI observations at 15, 43, and 86 GHz. Ground-space fringes were obtained up to a projected baseline of 3.9 Earth diameters during the perigee session, and at a record 15.1 Earth diameters during the snapshot sessions, allowing us to image the innermost jet at an angular resolution of $\sim 50\mu$as, the highest ever achieved at 22 GHz for OJ 287. Comparison with ground-based VLBI observations reveals a progressive jet bending with increasing angular resolution that agrees with predictions from a supermassive binary black hole model, although other models cannot be ruled out. Spectral analyses suggest that the VLBI core is dominated by the internal energy of the emitting particles during the onset of a multi-wavelength flare, while the parsec-scale jet is consistent with being in equipartition between the particles and magnetic field. Estimated minimum brightness temperatures from the visibility amplitudes show a continued rising trend with projected baseline length up to $10^{13}$ K, reconciled with the inverse Compton limit through Doppler boosting for a jet closely oriented to the line of sight. The observed electric vector position angle suggests that the innermost jet has a predominantly toroidal magnetic field, which together with marginal evidence of a gradient in rotation measure across the jet width indicate that the VLBI core is threaded by a helical magnetic field, in agreement with jet formation models.

References in corpus (65)

• Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Interpretation
• First M87 Event Horizon Telescope Results. I. The Shadow of the Supermassive Black Hole
• First M87 Event Horizon Telescope Results. VI. The Shadow and Mass of the Central Black Hole
• First M87 Event Horizon Telescope Results. IV. Imaging the Central Supermassive Black Hole
• First M87 Event Horizon Telescope Results. V. Physical Origin of the Asymmetric Ring
• First M87 Event Horizon Telescope Results. II. Array and Instrumentation
• First M87 Event Horizon Telescope Results. III. Data Processing and Calibration
• Polarimetric Observations of 15 Active Galactic Nuclei at High Frequencies: Jet Kinematics from Bimonthly Monitoring with the Very Long Baseline Array
• First M87 Event Horizon Telescope Results. VIII. Magnetic Field Structure near The Event Horizon
• Blazars in the Fermi Era: The OVRO 40-m Telescope Monitoring Program
• MOJAVE: Monitoring of Jets in Active Galactic Nuclei with VLBA Experiments. VI. Kinematics Analysis of a Complete Sample of Blazar Jets
• First M87 Event Horizon Telescope Results. VII. Polarization of the Ring
• Formation of Precessing Jets by Tilted Black-hole Discs in 3D General Relativistic MHD Simulations
• Instability of toroidal magnetic field in jets and plerions
• Kinematics of Parsec-Scale Jets of Gamma-Ray Blazars at 43~GHz within the VLBA-BU-BLAZAR Program
• DiFX: A software correlator for very long baseline interferometry using multi-processor computing environments
• MOJAVE: XV. VLBA 15 GHz Total Intensity and Polarization Maps of 437 Parsec-Scale AGN Jets From 1996-2017
• MOJAVE: Monitoring of Jets in Active Galactic Nuclei with VLBA Experiments. VIII. Faraday rotation in parsec-scale AGN jets
• MOJAVE XIII. Parsec-Scale AGN Jet Kinematics Analysis Based on 19 years of VLBA Observations at 15 GHz
• Multiwaveband Polarimetric Observations of 15 Active Galactic Nuclei at High Frequencies: Correlated Polarization Behavior
• Helical Magnetic Fields Associated with the Relativistic Jets of Four BL Lac Objects
• Primary black hole spin in OJ287 as determined by the General Relativity centenary flare
• Single-epoch VLBI imaging study of bright active galactic nuclei at 2 and 8 GHz
• Probing the innermost regions of AGN jets and their magnetic fields with RadioAstron. I. Imaging BL Lacertae at 21 microarcsecond resolution
• Survey of Instantaneous 1-22 GHz Spectra of 550 Compact Extragalactic Objects with Declinations from -30deg to +43deg
• Recollimation Shocks in Magnetized Relativistic Jets
• The VLBA Galactic Plane Survey -- VGaPS
• Three dimensional magnetic field structure of six parsec-scale active galactic nuclei jets
• Monthly 43 GHz VLBA Polarimetric Monitoring of 3C120 over 16 Epochs: Evidence for Trailing Shocks in a Relativistic Jet
• 3D Simulations of Relativistic Precessing Jets Probing the Structure of Superluminal Sources
• RadioAstron Observations of the Quasar 3C273: a Challenge to the Brightness Temperature Limit
• Erratic Jet Wobbling in the BL Lacertae Object OJ287 Revealed by Sixteen Years of 7mm VLBA Observations
• Radio observations of active galactic nuclei with mm-VLBI
• Relativistic Outflow Drives Gamma-Ray Emission in 3C345
• On the masses of OJ287 black holes
• POLAMI: Polarimetric Monitoring of Active Galactic Nuclei at Millimetre Wavelengths. I. The program, calibration, and calibrators data products
• POLAMI: Polarimetric Monitoring of Active Galactic Nuclei at Millimetre Wavelengths. III. Characterisation of total flux density and polarisation variability of relativistic jets
• Optical polarization of high-energy BL Lac objects
• Location of Gamma-ray emission and magnetic field strengths in OJ 287
• Spectral Evolution of The Parsec-Scale Jet in The Quasar 3C345
• Total and linearly polarized synchrotron emission from overpressured magnetized relativistic jets
• Are There Rotation Measure Gradients Across AGN Jets?
• Probing the innermost regions of AGN jets and their magnetic fields with RadioAstron II. Observations of 3C 273 at minimum activity
• A helical jet model for OJ287
• Explaining temporal variations in the jet position angle of the blazar OJ 287 using its binary black hole central engine model
• Optical polarization angle and VLBI jet direction in the binary black hole model of OJ287
• Software correlator for Radioastron mission
• Resolution limits in astronomical images
• Brightness temperature constraints from interferometric visibilities
• X-ray spectral components of the blazar and binary black hole candidate OJ 287 (2005-2020)
• Detection statistics of the RadioAstron AGN survey
• F-GAMMA: Multi-frequency radio monitoring of Fermi blazars. The 2.64 to 43 GHz Effelsberg light curves from 2007-2015
• RadioAstron space VLBI imaging of polarized radio emission in the high-redshift quasar 0642+449 at 1.6 GHz
• The magnetic field structure in CTA 102 from high resolution mm-VLBI observations during the flaring state in 2016-2017
• Very Long Baseline polarimetry and the gamma-ray connection in Markarian 421 during the broadband campaign in 2011
• On the non-thermal electron-to-proton ratio at cosmic acceleration sites
• Is OJ 287 a Single Supermassive Black Hole?
• Multi-frequency study of the gamma-ray flaring BL Lac object PKS 2233-148 in 2009-2012
• High cadence, linear and circular polarization monitoring of OJ 287 - Helical magnetic field in a bent jet
• RadioAstron reveals a spine-sheath jet structure in 3C 273
• The minimum jet power and equipartition
• Probing the innermost regions of AGN jets and their magnetic fields with RadioAstron. III. Blazar S5 0716+71 at microarcsecond resolution
• Localizing the $\gamma$-ray emitting region in the blazar TXS 2013+370
• Probing the innermost regions of AGN jets and their magnetic fields with RadioAstron IV. The quasar 3C 345 at 18 cm: Magnetic field structure and brightness temperature
• Optical Emission and Particle Acceleration in a Quasi-Stationary Component in the Jet of OJ~287