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arXiv · 1206.4571

A Fully-Identified Sample of AEGIS20 Microjansky Radio Sources

S. P. Willner·M. L. N. Ashby·P. Barmby·S. C. Chapman·A. Coil·M. Cooper·J. -S. Huang·R. Ivison·D. C. Koo
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Abstract

Infrared 3.6 to 8 micron images of the Extended Groth Strip yield plausible counterpart identifications for all but one of 510 radio sources in the AEGIS20 S(1.4 GHz) > 50 micro-Jy sample. This is the first such deep sample that has been effectively 100% identified. Achieving the same identification rate at R-band would require observations reaching R_AB > 27. Spectroscopic redshifts are available for 46% of the sample and photometric redshifts for an additional 47%. Almost all of the sources with 3.6 micron AB magnitudes brighter than 19 have spectroscopic redshifts z < 1.1, while fainter objects predominantly have photometric redshifts with 1 \lapprox z \lapprox 3. Unlike more powerful radio sources that are hosted by galaxies having large stellar masses within a relatively narrow range, the AEGIS20 counterparts have stellar masses spanning more than a factor of 10 at z \sim 1. The sources are roughly 10--15% starbursts at z \lapprox 0.5 and 20--25% AGNs mostly at z > 1 with the remainder of uncertain nature.

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S. P. Willner, M. L. N. Ashby, P. Barmby, S. C. Chapman, A. Coil, M. Cooper, J. -S. Huang, R. Ivison, D. C. Koo. 2012-06-20. A Fully-Identified Sample of AEGIS20 Microjansky Radio Sources. https://doi.org/10.1088/0004-637x/756/1/72

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