WISE J233237.05-505643.5: A Double-peaked, Broad-lined Active Galactic Nucleus with a Spiral-shaped Radio Morphology
Tsai, Chao-Wei; Kong, Albert K. H.; Norris, Ray P.; Eisenhardt, Peter R. M.; Stern, Daniel; Stubbs, Christopher W.; Barrows, R. Scott; Assef, Roberto J.; Emonts, Bjorn; Stalder, Brian; Li, K. L.; Wu, Jingwen; Jarrett, T. H.; Lonsdale, Carol; Blain, Andrew W.; Benford, Dominic J.; High, F. William
United States, South Africa, Spain, Australia, Chile, United Kingdom, Taiwan
Abstract
We present radio continuum mapping, optical imaging, and spectroscopy of the newly discovered double-peaked, broad-lined active galactic nucleus (AGN) WISE J233237.05-505643.5 at redshift z = 0.3447. This source exhibits an FR-I and FR-II hybrid morphology, characterized by a bright core, jet, and Doppler-boosted lobe structures in Australian Telescope Compact Array continuum maps at 1.5, 5.6, and 9 GHz. Unlike most FR-II objects, W2332-5056 is hosted by a disk-like galaxy. The core has a projected 5'' linear radio feature that is perpendicular to the curved primary jet, hinting at unusual and complex activity within the inner 25 kpc. The multi-epoch, optical-near-IR photometric measurements indicate significant variability over a 3-20 yr baseline from the AGN component. Gemini South optical data show unusual double-peaked emission-line features: the centroids of the broad-lined components of Hα and Hβ are blueshifted with respect to the narrow lines and host galaxy by ~3800 km s-1. We examine possible cases that involve single or double supermassive black holes in the system and discuss the required future investigations to disentangle the mysterious nature of this system.