Abstract
We present the unique and challenging case of a radio galaxy in Abell 3266 observed as part of the MeerKAT Galaxy Cluster Legacy Survey. It has quasi-periodic bright patches along the tail which connect to never-before-seen thin transverse extensions, which we call “ribs”, reaching up to ∼50 kpc from the central axis of the tail. At a distance of ∼400 kpc from the host (assuming the z=0.0594 redshift of Abell 3266) we found what appears to be a triple source with its own apparent host at a photometric redshift of 0.78. Mysteriously, the part of the tail far from the host and the triple are connected by a series of thin filaments, which we call “tethers”. The far tail, tethers and triple also have similar spectra and Faraday rotation measures, suggesting that there is only one—quite complicated—source, with a serendipitous background AGN in the triple. We look at possible causes for the “rib” and “tether” structures, and the emerging phenomena of intracluster medium filaments associated with radio galaxies.
Highlights
The sharp bend in the tail at ∼150 kpc from the core is accompanied by changes in the Faraday and magnetic field structure; these are likely signatures of a change in the physical and/or dynamical properties of the local intracluster medium (ICM)
MysTail presents several mysteries, with properties that do not fit cleanly into our current models of radio galaxies. It is not clear whether this is even a standard twin-tailed source, with the tails merged in projection or physically, or whether it is new type of one-sided structure
While a variety of factors could be responsible for the bright patches down the tail and the accompanying “ribs”, none of them satisfactorily accounts for all the observed properties
Summary
Cluster Legacy Survey (MGCLS; Knowles et al [1]). Details of the observations and map production are given there, but we include a brief summary here. In addition to the cluster radio galaxies, there are approximately 15 compact radio sources with peak fluxes > 0.3 mJy beam−1 , within 1.2 × 105 square arcseconds; the chances of being located somewhere within the jet-like structures is less than a few percent. Coincident with the presumed core, we found a faint optical/IR galaxy (DES J043118.45611917.9 WISEA J043118.50-611918.2) with a photometric redshift of 0.78 (Zou et al [6]). At this redshift, the 120-arcsec possible triple source would be 900 kpc in length; if the triple were an extension of the tail, it would be 140 kpc long. The connection between all of these structures is unclear, the interest in this source
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
