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We report the discovery of a grand-design spiral galaxy associated with a double-lobed radio source. J1649+2635 (z = 0.0545) is a red spiral galaxy with a prominent bulge that it is associated with a L$_{1.4{rm GHz}}sim$10$^{24}$WHz$^{-1}$ double-lob ed radio source that spans almost 100kpc. J1649+2635 has a black hole mass of M$_{rm BH} sim$ 3--7 $times$ 10$^8$M$_{odot}$ and SFR$sim$ 0.26 -- 2.6M$_{odot}$year$^{-1}$. The galaxy hosts a $sim$96kpc diffuse optical halo, which is unprecedented for spiral galaxies. We find that J1649+2635 resides in an overdense environment with a mass of M$_{dyn} = 7.7^{+7.9}_{-4.3} times 10^{13}$M$_{odot}$, likely a galaxy group below the detection threshold of the ROSAT All-Sky Survey. We suggest one possible scenario for the association of double-lobed radio emission from J1649+2635 is that the source may be similar to a Seyfert galaxy, located in a denser-than-normal environment. The study of spiral galaxies that host large-scale radio emission is important because although rare in the local Universe, these sources may be more common at high-redshifts.
The extreme ULIRG F00183-7111 has recently been found to have a radio-loud AGN with jets in its centre, representing an extreme example of the class of radio-loud AGNs buried within dusty star-forming galaxies. This source appears to be a rare exampl e of a ULIRG glimpsed in the (presumably) brief period as it changes from quasar mode to radio mode activity. Such transition stages probably account for many of the high-redshift radio-galaxies and extreme high-redshift ULIRGs, and so this object at the relatively low redshift of 0.328 offers a rare opportunity to study this class of objects in detail. We have also detected the CO signal from this galaxy with the ATCA, and here describe the implications of this detection for future ULIRG studies.
The Australia Telescope Large Area Survey (ATLAS) has surveyed seven square degrees of sky around the Chandra Deep Field South (CDFS) and the European Large Area ISO Survey - South 1 (ELAIS-S1) fields at 1.4 GHz. ATLAS aims to reach a uniform sensiti vity of $10 mu$Jy beam$^{-1}$ rms over the entire region with data release 1 currently reaching $sim30 mu$Jy beam$^{-1}$ rms. Here we present 466 new spectroscopic redshifts for radio sources in ATLAS as part of our optical follow-up program. Of the 466 radio sources with new spectroscopic redshifts, 142 have star-forming optical spectra, 282 show evidence for AGN in their optical spectra, 10 have stellar spectra and 32 have spectra revealing redshifts, but with insufficient features to classify. We compare our spectroscopic classifications with two mid-infrared diagnostics and find them to be in broad agreement. We also construct the radio luminosity function for star-forming galaxies to z $= 0.5$ and for AGN to z $= 0.8$. The radio luminosity function for star-forming galaxies appears to be in good agreement with previous studies. The radio luminosity function for AGN appears higher than previous studies of the local AGN radio luminosity function. We explore the possibility of evolution, cosmic variance and classification techniques affecting the AGN radio luminosity function. ATLAS is a pathfinder for the forthcoming EMU survey and the data presented in this paper will be used to guide EMUs survey design and early science papers.
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