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A sample of radio galaxies spanning three decades in radio luminosity - I. The host-galaxy properties and black-hole masses

Ross J. McLure·Chris J. Willott·Matt J. Jarvis·Steve Rawlings·Gary J. Hill·Ewan Mitchell·James S. Dunlop·Margrethe Wold
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Abstract

The results of analysis of HST I-band imaging of a sample of 41 radio galaxies spanning three orders of magnitude in radio luminosity at redshift z~0.5 are presented. The full sample is drawn from four complete, low-frequency selected radio samples with progressively fainter flux-density limits (3CRR, 6CE, 7CRS and the new TexOx-1000 sample). Modelling of the HST imaging data shows that the host galaxies have surface-brightness distributions consistent with those expected for classic ellipticals (Sersic parameter, beta~0.25), with beta in the range 0.17 =0.23\pm0.01. The host-galaxy luminosities are comparable with those of galaxies drawn from the bright end of the local cluster galaxy luminosity function, spanning the range 0.7L^{\star} =10^{8.87\pm 0.04}\Msun. Finally, a significant (~3 sigma) correlation is found between black-hole mass and 151-MHz radio luminosity for those objects in the sample with either high-excitation nuclear spectra or classical double radio structures. (abridged)

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Ross J. McLure, Chris J. Willott, Matt J. Jarvis, Steve Rawlings, Gary J. Hill, Ewan Mitchell, James S. Dunlop, Margrethe Wold. 2004-03-04. A sample of radio galaxies spanning three decades in radio luminosity - I. The host-galaxy properties and black-hole masses. https://doi.org/10.1111/j.1365-2966.2004.07793.x

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