AGN feedback through multiple jet cycles in the Seyfert galaxy NGC 2639.

The Seyfert galaxy NGC 2639 was known to exhibit three episodes of active galactic nuclei (AGN) jet/lobe activity. We present here the upgraded Giant Metrewave Radio Telescope (uGMRT) 735 MHz image of NGC 2639 showing a fourth episode as witnessed by the discovery of ∼9 kpc radio lobes misaligned with the previously known ∼1.5 kpc, ∼360 pc, and ∼3 pc jet features detected through the Karl G. Jansky Very Large Array (VLA) and the Very Long Baseline Array (VLBA), respectively. Using the spectral ageing software brats , we derive the ages of the ∼9 kpc, ∼1.5 kpc, and ∼360 pc episodes to be, respectively, |$34^{+4}_{-6}$|⁠ , |$11.8^{+1.7}_{-1.4}$|⁠ , and |$2.8^{+0.7}_{-0.5}$| Myr, and conclude that minor mergers occurred 9−22 Myr apart. NGC 2639 shows a deficit of molecular gas in its central ∼6 kpc region. The GALEX NUV image also shows a deficiency of recent star formation in the same region, while the star formation rate surface density in NGC 2639 is lower by a factor of 5−18 compared to the global Schmidt law of star-forming galaxies. This makes NGC 2639 a rare case of a Seyfert galaxy showing episodic jet activity and possible signatures of jet-driven AGN feedback. [ABSTRACT FROM AUTHOR]