| 12th of May 2015 |
|---|
|
| The Faintest Dying Radio Galaxy |
| by Natasha Hurley-Walker (Curtin University) |
| In
this paper we
report the discovery of the lowest surface brightness
radio galaxy yet detected, associated with the lenticular galaxy NGC 1534.
This represents only the seventh detection of large-scale radio lobes
associated with a galaxy containing a dust lane. Additionally, NGC 1534 has
the steepest spectral index and lowest power of galaxies of this type. The
lack of jets, hotspots and an obvious radio core associated with the
optical host along with the non-detection of significant neutral hydrogen,
despite the obvious dust lane, suggest that this is a true "relic"
radio galaxy. This new detection was made possible by the excellent surface
brightness sensitivity, wide field-of-view, and low observing frequency of
the Murchison Widefield Array (MWA). The image shows MWA 185-MHz contours starting at 2 and proceeding in = 100 mJy increments, overlaid on the Digitized Sky Survey (DSS) Red image. NGC 1534 can be seen at the top of the southern lobe. The inset shows a false color image of NGC 1534, marked on the main image with a square; red represents the UK Schmidt infra-red image, green the European Southern Observatory Red image, and blue the UK Schmidt Blue image. A dust lane is clearly visible. Reference: Hurley-Walker et al. 2015, MNRAS 447, 2468 |