The blazar OJ 287 jet from parsec- to kiloparsec-scales

TL;DR

This study investigates the curved kiloparsec-scale jet of blazar OJ 287, analyzing its shape and velocity through precession models, and compares two X-ray emission mechanisms to explain observed data and jet behavior.

Contribution

It introduces a comparative analysis of X-ray emission mechanisms for the OJ 287 jet and links jet precession to the central engine's activity, providing new insights into jet dynamics.

Findings

The jet's helix period matches the central engine's precession period.

Gamma-ray flux predictions align with Fermi-LAT data under the central source radiation model.

The jet's shape supports the precession-driven model of jet curvature.

Abstract

The curved shape of the kiloparsec-scale jet of the blazar OJ 287 is analyzed in the framework of the precession of the central engine, on the existence on which a large number of studies over the past decades are based. The data necessary for the analysis of the kiloparsec-scale jet velocity and angle with the line of sight are obtained based on two competing assumptions about the X-ray emission mechanism of the OJ 287 jet. Namely, there were both the inverse Compton scattering of the microwave background under the assumption of relativistic kiloparsec-scale jet and the inverse Compton scattering of the central source radiation. For the latter one, we showed that the expected flux from the kiloparsec-scale jet in the gamma range does not exceed the limit set for it according to Fermi-LAT data. We found that only the period of the kiloparsec-scale jet helix, estimated in the framework of the inverse Compton scattering of the central source radiation, agrees with the precession period of the central engine, determined from the modulation of the peak values of 12-year optical flares.