Serendipitous discovery of a dying Giant Radio Galaxy associated with NGC 1534, using the Murchison Widefield Array

Hurley-Walker, Natasha, Johnston-Hollitt, Melanie, Ekers, Ron, Hunstead, Richard, Sadler, Elaine M., Hindson, Luke, Hancock, Paul, Bernardi, Gianni, Bowman, Judd D., Briggs, Frank, Cappallo, Roger, Corey, Brian, Deshpande, Avinash A., Emrich, David, Gaensler, Bryan M., Goeke, Robert, Greenhill, Lincoln, Hazelton, Bryna J., Hewitt, Jacqueline, Kaplan, David L., Kasper, Justin, Kratzenberg, Eric, Lonsdale, Colin, Lynch, Mervyn, Mitchell, Daniel, McWhirter, Russell, Morales, Miguel, Morgan, Edward, Oberoi, Divya, Offringa, Andre, Ord, Stephen, Prabu, Thiagaraj, Rogers, Alan, Roshi, Anish, Shankar, Udaya, Srivani, K., Subrahmanyan, Ravi, Tingay, Steven, Waterson, Mark, Wayth, Randall B., Webster, Rachel, Whitney, Alan, Williams, Andrew and Williams, Chris (2015) Serendipitous discovery of a dying Giant Radio Galaxy associated with NGC 1534, using the Murchison Widefield Array. Monthly Notices of the Royal Astronomical Society (MNRAS), 447 (3). pp. 2468-2478. ISSN 0035-8711

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Recent observations with the Murchison Widefield Array at 185~MHz have serendipitously unveiled a heretofore unknown giant and relatively nearby ($z = 0.0178$) radio galaxy associated with NGC\,1534. The diffuse emission presented here is the first indication that NGC\,1534 is one of a rare class of objects (along with NGC\,5128 and NGC\,612) in which a galaxy with a prominent dust lane hosts radio emission on scales of $\sim$700\,kpc. We present details of the radio emission along with a detailed comparison with other radio galaxies with disks. NGC1534 is the lowest surface brightness radio galaxy known with an estimated scaled 1.4-GHz surface brightness of just 0.2\,mJy\,arcmin$^{-2}$. The radio lobes have one of the steepest spectral indices yet observed: $\alpha=-2.1\pm0.1$, and the core to lobe luminosity ratio is $

Item Type	Article
Additional information	This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society. © 2015 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society.
Keywords	astro-ph.ga
Date Deposited	15 May 2025 13:10
Last Modified	31 May 2025 00:05