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arXiv · 0801.1035

An evolution of the IR-Radio correlation at very low flux densities?

R. J. Beswick·T. W. B. Muxlow·H. Thrall·A. M. S. Richards·S. T. Garrington
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Abstract

In this paper we investigate the radio-MIR correlation at very low flux densities using extremely deep 1.4 GHz sub-arcsecond angular resolution MERLIN+VLA observations of a 8'.5 by 8'.5 field centred upon the Hubble Deep Field North, in conjunction with Spitzer 24micron data. From these results the MIR-radio correlation is extended to the very faint (~microJy) radio source population. Tentatively we detect a small deviation from the correlation at the faintest IR flux densities. We suggest that this small observed change in the gradient of the correlation is the result of a suppression of the MIR emission in faint star-forming galaxies. This deviation potentially has significant implications for using either the MIR or non-thermal radio emission as a star-formation tracer of very low luminosity galaxies.

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R. J. Beswick, T. W. B. Muxlow, H. Thrall, A. M. S. Richards, S. T. Garrington. 2008-01-07. An evolution of the IR-Radio correlation at very low flux densities?. https://doi.org/10.1111/j.1365-2966.2008.12931.x

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