Kinematics of AGN Jets

TL;DR

This paper reviews high-resolution VLBI observations of AGN jets, revealing their linear and curved structures, relativistic speeds with high Lorentz factors, and discusses their relation to gamma-ray observations.

Contribution

It provides a comprehensive analysis of AGN jet kinematics using VLBI data from multiple surveys and links radio jet properties with gamma-ray observations.

Findings

Most jets show linear morphology at parsec scales.

Jets exhibit relativistic speeds with Lorentz factors above 30.

Some jets display curvature and non-radial motions.

Abstract

The fine-scale structure and the kinematics of relativistic active galactic nuclei (AGN) jets have been studied by very-long-baseline interferometry at very high resolutions since 1998 at 2 cm wavelength for a sample of over a hundred radio sources (VLBA 2cm Survey and MOJAVE programs). Since 2007, this is being complemented by the TANAMI project, based on southern observations with the Australian LBA at 3.6 cm and 1.1 cm wavelengths. From our observation campaign, we find that most of the radio jets show linear morphologies at parsec-scales, but some of show curvature and non-radial motions. Features are observed to move at highly relativistic speeds, with Lorentz factors extending above values of 30. We also provide a brief description of the relationship of our radio findings with the AGN observations by the new Fermi Gamma-ray Space Telescope.