Compact Symmetric Objects and Supermassive Binary Black Holes in the VLBA Imaging and Polarimetry Survey

TL;DR

This study uses VLBA observations to identify and analyze compact symmetric objects (CSOs) and supermassive binary black holes, providing a large uniform sample to understand their properties and evolution.

Contribution

It presents the first large uniform sample of CSOs, refutes many SBBH candidates, and reports polarised emission detection, advancing understanding of these sources.

Findings

Identified 24 CSOs, including 15 newly designated.

Refuted 52 SBBH candidates, leaving 33 unconfirmed.

Detected polarised emission in two CSOs.

Abstract

We present multi-frequency Very Long Baseline Array (VLBA) follow-up observations of VLBA Imaging and Polarimetry Survey sources identified as likely compact symmetric objects (CSOs) or super-massive binary black holes (SBBHs). We also present new spectroscopic redshifts for 11 sources observed with the Hobby-Eberly Telescope. While no new SBBHs can be confirmed from these observations, we have identified 24 CSOs in the sample, 15 of which are newly designated, and refuted 52 candidates leaving 33 unconfirmed candidates. This is the first large uniform sample of CSOs which can be used to elicit some of the general properties of these sources, including morphological evolution and environmental interaction. We have detected polarised emission from two of these CSOs the properties of which are consistent with Active Galactic Nuclei unification schemes.