Extended Radio Structures and a Compact X-Ray Cool-core in the Cluster Source PKS 1353-341
Abstract
We present a radio and X-ray study of PKS 1353-341, the brightest cluster galaxy radio source at the center of a recent Chandra-discovered X-ray cluster. Our multi-frequency Very Large Array images reveal an edge-brightened (FR-II), double-lobed structure with a total ∼50 kpc extent, and 1.5 GHz power of 1.2 × 1025 W Hz-1, separated from the bright, arcsecond-scale core. We reanalyzed the Chandra data and found that the X-ray-emitting active galactic nucleus (AGN) is offset by ∼9 kpc from a compact X-ray cool-core with temperature kT = 3.1 ± 0.5 keV, and a radius of ∼22 kpc, surrounded by a hotter kT = 6.3 ± 0.7 keV gas out to ∼50 kpc. The offset suggests sloshing inside the cool-core induced by a minor merger or a past outburst of the AGN that produced large-scale radio lobes. The comparable spatial scales of the lobes with the interface between the different temperature X-ray plasmas indicate the lobes are actively heating the outer layers of what is now a remnant compact cool-core. Our dual-frequency Very Long Baseline Array (VLBA) images reveal substructure in the central radio source, consisting of a radio core with double-sided parsec-scale jets pointing toward the kiloparsec-scale structures. The northern jet is detected only at 8.4 GHz, indicating its emission is behind an absorbing torus or disk. We also measured faster apparent motions in the southern jet up to 1.9 ± 1.1c than in the northern jet (0.8 ± 0.5c). While the VLBA observations indicate the southern jet is aligned slightly closer to our line of sight, the asymmetries are overall modest and imply minimal projection effects in the large-scale radio structures.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- April 2019
- DOI:
- 10.3847/1538-4357/ab100b
- arXiv:
- arXiv:1903.08044
- Bibcode:
- 2019ApJ...875..108C
- Keywords:
-
- galaxies: active;
- galaxies: clusters: individual: PKS 1353–341;
- galaxies: jets;
- radio continuum: galaxies;
- X-rays: general;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- 16 pages, ApJ accepted