4C 32.26

Lore & Background

4C 32.26 was first identified as an astronomical radio source by astronomers conducting the Fourth Cambridge Survey in 1969. Its host is a large elliptical galaxy with a central component and a western component displaced by 70 kiloparsecs. Studies show the host has an undisturbed appearance without signs of a major galaxy merger, though it interacts with other cluster members. A faint companion lies 11 arcseconds away.

The radio structure of 4C 32.26 is compact, reminiscent of Fanaroff-Riley Class Type II sources, with a total flux density of 7.5 MJy. Observations at 1.4 GHz with the Very Large Array (VLA) showed a compact source surrounded by radio emission. At 4.9 GHz, an inner source with two radio lobes spans about 16 kiloparsecs, with much fainter asymmetric lobes extending 150 kiloparsecs from the nucleus. A jet appears to lead toward a faint lobe but is at 90° in projection. The galaxy is considered a restarted source: the first pair of lobes are old and no longer fueled, while the second pair are young, with ages between 3 and 7 million years. Earlier observations found two jet-like structures ending in hotspot positions.

A study found an extended emission line region (EELR) based on narrow-band optical imaging, with emission mainly concentrated on the host galaxy.

Reader's Guide

4C 32.26 is significant as a restarted radio galaxy, providing evidence for episodic jet activity in elliptical galaxies. Its classification as both a wide-angle tail and weak radio galaxy, along with its compact radio structure reminiscent of Fanaroff-Riley Class Type II sources, offers insight into the diversity of radio morphologies. The presence of an extended emission line region (EELR) concentrated on the host galaxy indicates ongoing interactions with the intracluster medium. As the brightest cluster galaxy (BCG) of Abell 695 and part of a dumbbell system, it serves as a key object for studying galaxy evolution in dense cluster environments. The undisturbed appearance of its host, despite interactions with cluster members, suggests that major mergers are not required to trigger restarted radio activity. The age estimates of its young lobes (3–7 million years) provide a timescale for the most recent episode of nuclear activity.

Did You Know?

• Its host is a large elliptical galaxy with an undisturbed appearance and no signs of a major merger.
• The galaxy is a restarted source with young radio lobes aged between 3 and 7 million years.