Jet precession driven by a supermassive black hole binary system in the BL Lac object PG 1553+113

Abstract

The recent discovery of a roughly simultaneous periodic variability in the light curves of the BL Lac object PG 1553+113 at several electromagnetic bands represents the first case of such odd behavior reported in the literature. Motivated by this, we analyzed 15 GHz interferometric maps of the parsec-scale radio jet of PG 1553+113 to verify the presence of a possible counterpart of this periodic variability. We used the Cross-Entropy statistical technique to obtain the structural parameters of the Gaussian components present in the radio maps of this source. We kinematically identified seven jet components formed coincidentally with flare-like features seen in the $\gamma$-ray light curve. From the derived jet component positions in the sky plane and their kinematics (ejection epochs, proper motions, and sky position angles), we modeled their temporal changes in terms of a relativistic jet that is steadily precessing in time. Our results indicate a precession period in the observer's reference frame of $2.24\pm 0.03$ years, compatible with the periodicity detected in the light curves of PG 1553+113. However, the maxima of the jet Doppler boosting factor are systematically delayed relative to the peaks of the main $\gamma$-ray flares. We propose two scenarios that could explain this delay, both based on the existence of a supermassive black hole binary system in PG 1553+113. We estimated the characteristics of this putative binary system that also would be responsible for driving the inferred jet precession.

8 pages, 2 figures. Accepted for publication in The Astrophysical Journal Letters

References in corpus (11)

• The power of blazar jets
• MOJAVE: Monitoring of Jets in AGN with VLBA Experiments. V. Multi-epoch VLBA Images
• The Spectral Energy Distributions of Fermi Blazars
• A model for periodic blazars
• Optical polarization of high-energy BL Lac objects
• Systematic Study of Gamma-ray bright Blazars with Optical Polarization and Gamma-ray Variability
• Warping and precession in galactic and extragalactic accretion disks
• The RINGO2 and DIPOL Optical Polarisation Catalogue of Blazars
• First-Epoch VLBA Imaging of Twenty New TeV Blazars
• Radio-Gamma-ray connection and spectral evolution in 4C +49.22 (S4 1150+49): the Fermi, Swift and Planck view
• Kinematic study of the parsec-scale jet of the quasar PKS 1741--03

Cited by in corpus (10)

• Quasi-periodic behaviour in the optical and γ-ray light curves of blazars 3C 66A and B2 1633+38
• Looking at Blazar Light Curve Periodicities with Gaussian Processes
• Precession-induced Variability in AGN Jets and OJ 287
• A parsec-scale wobbling jet in the high-synchrotron peaked blazar PG 1553+113
• Optical Flux and Spectral Variability of the TeV blazar PG 1553+113
• Multi-band behaviour of the TeV blazar PG 1553+113 in optical range on diverse timescales
• Multi-band Variability of the TeV Blazar PG 1553+113 with XMM-Newton
• Double-peaked Lines, Dual VLBI Components, and Precessing Jets in J1328+2751
• The relativistic parsec-scale jets of the blazars TXS 0506+056 and PKS 0502+049 and their possible association with gamma-ray flares and neutrino production
• The variability patterns of the TeV blazar PG 1553+113 from a decade of MAGIC and multi-band observations