Variable broad lines and outflow in the weak blazar PBC J2333.9-2343

TL;DR

This study reveals significant variability and complex outflow phenomena in the weak blazar PBC J2333.9-2343 across optical, UV, and X-ray wavelengths, highlighting dynamic broad emission lines and jet-related ionization processes.

Contribution

The paper provides new multiwavelength observations showing variable broad emission lines and outflows, demonstrating jet influence on the broad and narrow line regions in this peculiar active nucleus.

Findings

Significant flux increase in broad Hα and X-ray flux between 2009-2016.

Detection of a broad Hβ component leading to a change in optical classification.

Identification of a high-velocity, blue-shifted [OIII] line indicating outflows.

Abstract

PBC J2333.9-2343 is a peculiar active nucleus with two giant radio lobes and a weak blazar-like nucleus at their center. In the present work we show new optical, UV, and X-ray data taken from the San Pedro M\'artir telescope, the New Technology Telescope, NTT/EFOSC2, and the Swift/XRT satellite. The source is highly variable at all frequencies, in particular the strongest variations are found in the broad H$\alpha$ component with a flux increase of 61$\pm$4 per cent between 2009 and 2016, following the X-ray flux increase of 62$\pm$6 per cent between 2010 and 2016. We also detected a broad H$\beta$ component in 2016, making the optical classification change from type 1.9 to type 1.8 in one year. We have also detected a broad component of the [OIII]$\lambda$5007 line, which is blue-shifted and of high velocity, suggesting an origin from a highly disturbed medium, possibly an outflow. The line flux variability and broad widths are indicative of a jet that is, at least in part, responsible for the ionization of the BLR and NLR.