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AEGIS20: a radio survey of the Extended Groth Strip

R. J. Ivison·S. C. Chapman·S. M. Faber·Ian Smail·A. D. Biggs·C. J. Conselice·G. Wilson·S. Salim·J. -S. Huang·S. P. Wilner
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Abstract

We describe AEGIS20 - a radio survey of the Extended Groth Strip (EGS) conducted with the Very Large Array (VLA) at 1.4GHz. The resulting catalog contains 1,123 emitters and is sensitive to ultraluminous starbursts to z<=1.3, well matched to the redshift range of the DEEP2 spectroscopic survey in this region. We use stacking techniques to explore the uJy-level emission from a variety of galaxy populations selected via conventional criteria - Lyman-break galaxies (LBGs), distant red galaxies (DRGs), UV-selected galaxies and extremely red objects (EROs) - determining their properties as a function of color, magnitude and redshift and their extinction-free contributions to the history of star formation. We confirm the familiar pattern that the star-formation-rate (SFR) density, SFRD, rises by at least ~5x from z=0-1, although we note highly discrepant UV- and radio-based SFR estimates. Our radio-based SFRs become more difficult to interpret at z>1 where correcting for contamination by radio-loud active galactic nuclei (AGN) comes at the price of rejecting luminous starbursts. Whilst stacking radio images is a useful technique, accurate radio-based SFRs for z>>1 galaxies require precise redshifts and extraordinarily high-fidelity radio data to identify and remove accretion-related emission.

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R. J. Ivison, S. C. Chapman, S. M. Faber, Ian Smail, A. D. Biggs, C. J. Conselice, G. Wilson, S. Salim, J. -S. Huang, S. P. Wilner. 2006-09-29. AEGIS20: a radio survey of the Extended Groth Strip. https://doi.org/10.1086/517917

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