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arXiv · 0812.2052

MRC B0319-454: Probing the large-scale structure with a giant radio galaxy

V. Safouris·R. Subrahmanyan·G. V. Bicknell·L. Saripalli
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Abstract

We present an investigation of the relationships between the radio properties of a giant radio galaxy MRC B0319-454 and the surrounding galaxy distribution with the aim of examining the influence of intergalactic gas and gravity associated with the large-scale structure on the evolution in the radio morphology. Our new radio continuum observations of the radio source, with high surface brightness sensitivity, images the asymmetries in the megaparsec-scale radio structure in total intensity and polarization. We compare these with the 3-D galaxy distribution derived from galaxy redshift surveys. Galaxy density gradients are observed along and perpendicular to the radio axis: the large-scale structure is consistent with a model wherein the galaxies trace the ambient intergalactic gas and the evolution of the radio structures are ram-pressure limited by this associated gas. Additionally, we have modeled the off-axis evolution of the south-west radio lobe as deflection of a buoyant jet backflow by a transverse gravitational field: the model is plausible if entrainment is small. The case study presented here is a demonstration that giant radio galaxies may be useful probes of the warm-hot intergalactic medium believed to be associated with moderately over dense galaxy distributions.

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V. Safouris, R. Subrahmanyan, G. V. Bicknell, L. Saripalli. 2008-12-10. MRC B0319-454: Probing the large-scale structure with a giant radio galaxy. https://doi.org/10.1111/j.1365-2966.2008.14181.x

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