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arXiv · 1008.5244

The stellar mass function of the most massive galaxies at 3<=z<5 in the UKIDSS Ultra Deep Survey

K. I. Caputi·M. Cirasuolo·J. S. Dunlop·R. J. McLure·D. Farrah·O. Almaini
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Abstract

We have analysed a sample of 1292 4.5 micron-selected galaxies at z>=3, over 0.6 square degrees of the UKIRT Infrared Deep Survey (UKIDSS) Ultra Deep Survey (UDS). Using photometry from the U band through 4.5 microns, we have obtained photometric redshifts and derived stellar masses for our sources. Only two of our galaxies potentially lie at z>5. We have studied the galaxy stellar mass function at 3<=z<5, based on the 1213 galaxies in our catalogue with [4.5]<= 24.0. We find that: i) the number density of M > 10^11 Msun galaxies increased by a factor > 10 between z=5 and 3, indicating that the assembly rate of these galaxies proceeded > 20 times faster at these redshifts than at 0 10^11 Msun galaxies would be missed by optical surveys with R<27 or z<26. Thus, our study demonstrates the importance of deep mid-IR surveys over large areas to perform a complete census of massive galaxies at high z and trace the early stages of massive galaxy assembly.

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K. I. Caputi, M. Cirasuolo, J. S. Dunlop, R. J. McLure, D. Farrah, O. Almaini. 2010-11-29. The stellar mass function of the most massive galaxies at 3<=z<5 in the UKIDSS Ultra Deep Survey. https://doi.org/10.1111/j.1365-2966.2010.18118.x

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