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arXiv · 1212.1234

Multi-Wavelength Study of a Complete IRAC 3.6micron-Selected Galaxy Sample: a Fair Census of Red and Blue Populations at Redshifts 0.4-1

J. -S. Huang·S. M. Faber·C. N. A. Willmer·D. Rigopoulou·D. Koo·J. Newman·C. Shu·M. L. N. Ashby·P. Barmby·A. Coil·Z. Luo·G. Magdis·T. Wang·B. Weiner·S. P. Willner·X. Z. Zheng·G. G. Fazio
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Abstract

We present a multi-wavelength study of a 3.6 $\mu$m-selected galaxy sample in the Extended Groth strip. The sample is complete for galaxies with stellar mass $>10^{9.5}$ \Msun and redshift $0.4 }3\sigma$ errors) is about 3.5%. A new method of validation based on pair statistics confirms the estimate of standard deviation even for galaxies lacking spectroscopic redshifts. Basic galaxy properties measured include rest-frame $U-B$ colors, $B$- and $K$-band absolute magnitudes, and stellar masses. We divide the sample into quiescent and star-forming galaxies according to their rest-frame $U-B$ colors and 24 to 3.6 \micron\ flux density ratios and derive rest $K$-band luminosity functions and stellar mass functions for quiescent, star forming, and all galaxies. The results show that massive, quiescent galaxies were in place by $z\approx1$, but lower mass galaxies generally ceased their star formation at later epochs.

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J. -S. Huang, S. M. Faber, C. N. A. Willmer, D. Rigopoulou, D. Koo, J. Newman, C. Shu, M. L. N. Ashby, P. Barmby, A. Coil, Z. Luo, G. Magdis, T. Wang, B. Weiner, S. P. Willner, X. Z. Zheng, G. G. Fazio. 2012-12-06. Multi-Wavelength Study of a Complete IRAC 3.6micron-Selected Galaxy Sample: a Fair Census of Red and Blue Populations at Redshifts 0.4-1. https://doi.org/10.1088/0004-637x%2F766%2F1%2F21

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