Enhanced UV emission knot in the giant radio galaxy NGC 315: hint of patchy star formation?

Document Type

Article

Publication Title

Monthly Notices of the Royal Astronomical Society

Abstract

High-resolution AstroSat-UltraViolet Imaging Telescope (UVIT) observations revealed a knot of UV emission, ~ 1.7 kpc away from the centre of NGC 315, a nearby elliptical galaxy hosting a giant (Mpc scale) radio source with a jet. We suggest that this patchy and spatially extended UV emission is likely due to ongoing star formation (SF) in the galaxy. The estimated star formation rate (SFR) averaged over 100 Myr for the UV knot (0.23 ± 0.10 M⊙ yr-1) is significantly higher compared to a typical elliptical galaxy. As the galaxy does not show the signatures of recent major mergers, the possible mechanisms for the triggered SF include active galactic nucleus (AGN) feedback or minor mergers. Hubble Space Telescope observations reveal dust filaments that extend through a UV knot. The origin of dusty filaments, though not clear, could be associated with gas clouds as a result of a minor merger, cooled gas falling into the central brightest cluster galaxy and/or condensing of the gas uplifted by AGN jet. No significant clumpy UV emission is observed in other regions along the dust filament. We speculate that mechanical feedback from the AGN jet could be playing a role in triggering SF in the UV knot.

First Page

3394

Last Page

3406

DOI

10.1093/mnras/staf1852

Publication Date

12-1-2025

This document is currently not available here.

Share

COinS