Investigating the Effects of Finite Resolution on Observed Transverse Jet Profiles

Abstract

Both the emission properties and evolution of Active Galactic Nuclei (AGN) radio jets are dependent on the magnetic fields that thread them. Faraday Rotation gradients are a very important way of investigating these magnetic fields, and can provide information on the orientation and structure of the magnetic field in the immediate vicinity of the jet; for example, a toroidal or helical field component should give rise to a systematic gradient in the observed Faraday rotation across the jet, as well as characteristic intensity and polarization profiles. However, real observed radio images have finite resolution, usually expressed via convolution with a Gaussian beam whose size corresponds to the central lobe of the point source response function. This will tend to blur transverse structure in the jet profile, raising the question of how well resolved a jet must be in the transverse direction in order to reliably detect transverse structure associated with a helical jet magnetic field. We present results of simulated intensity, polarization and Faraday rotation images designed to directly and empirically investigate the effect of finite resolution on observed transverse jet structures.

References in corpus (2)

• Radio Circular Polarization Produced in Helical Magnetic Fields in Eight Active Galactic Nuclei
• Multifrequency Polarimetry of the Nrao 140 Jet: Possible Detection of a Helical Magnetic Field and Constraints on its Pitch Angle

Cited by in corpus (4)

• MOJAVE: Monitoring of Jets in Active Galactic Nuclei with VLBA Experiments. VIII. Faraday rotation in parsec-scale AGN jets
• Connecting Magnetic Towers with Faraday Rotation Gradients in Active Galactic Nuclei Jets
• The Spiderweb proto-cluster is being magnetized by its central radio jet
• High resolution VLBI polarisation imaging of AGN with the Maximum Entropy Method