Discovery of A Large-scale Bent Radio Jet in the Merging Cluster A514

Abstract

We report a discovery of a large-scale bent radio jet in the merging galaxy cluster A514 ( z = 0.071). The radio emission originates from the two radio lobes of the active galactic nucleus (AGN) located near the center of the southern subcluster and extends toward the southern outskirts with multiple bends. Its peculiar morphology is characterized by a 400 kpc “bridge,” a 300 kpc “arc,” and a 400 kpc “tail,” which together contribute to its largest linear size of ∼0.7 Mpc. We find that both the flux and spectral features of the emission change with the distance from the AGN. Also, the “bridge” presents a 60% polarized radio emission, which coincided with an X-ray cold front. Based on our multiwavelength observations, we propose that A514 presents a clear case for the redistribution of an old AGN plasma due to merger-driven gas motions. We support our interpretation with idealized cluster merger simulations employing a passive tracer field to represent cosmic-ray electrons and find that merger-driven motions can efficiently create a cloud of these particles in the cluster outskirts, which later can be reaccelerated by the cluster merger shock and produce radio relics.

Keywords

• Galaxy clusters
• Abell clusters
• Radio jets