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arXiv · 1902.02356

Studying galaxy evolution through cosmic time via the μJy radio population: early results from eMERGE

A. P. Thomson·T. W. B. Muxlow·Ian Smail·I. M McHardy·R. J. Beswick·J. F. Radcliffe·N. Wrigley
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Abstract

The $e$MERLIN Galaxy Evolution Survey ($e$MERGE) is an ambitious, multi-tiered extragalactic radio continuum survey being carried out with $e$MERLIN and the VLA at 1.4GHz and 6GHz. Exploiting the unique combination of high sensitivity and high angular resolution provided by radio interferometry, these observations will provide a powerful, obscuration-independent tool for tracing intense star-formation and AGN activity in galaxies out to $z\sim5$. In our first data release (DR1) we present $e$MERGE Tier 1, a 15-arcmin pointing centred on the GOODS-N field, imaged at 1.4GHz with the VLA and $e$MERLIN at $\sim 0.28''$ resolution down to an rms sensitivity of $\sim 1.2\,μ$Jy beam$^{-1}$. This unique radio survey -- unrivaled at 1.4GHz in its combination of depth, areal coverage and angular resolution in the pre-SKA era -- allows us to localise and separate extended star-forming regions, nuclear starbursts and compact AGN core/jet systems in galaxies over the past two-thirds of cosmic history, a crucial step in tracing the apparently simultaneous growths of the stellar populations and central black holes in massive galaxies. In these proceedings we highlight some early science results from $e$MERGE DR1, including some examples of the sub-arcsecond morphologies and cold dust properties of 1.4GHz-selected galaxies. $e$MERGE Tier 1 will eventually reach sub-$μ$Jy beam$^{-1}$ sensitivity at $0.28''$ resolution over a 30-arcmin field, providing crucial benchmarks for deep extragalactic surveys which will be undertaken with SKA in the next decade.

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A. P. Thomson, T. W. B. Muxlow, Ian Smail, I. M McHardy, R. J. Beswick, J. F. Radcliffe, N. Wrigley. 2019-02-06. Studying galaxy evolution through cosmic time via the μJy radio population: early results from eMERGE. https://arxiv.org/abs/1902.02356

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