Article

Insights on the Formation, Evolution, and Activity of Massive Galaxies from Ultracompact and Disky Galaxies at z = 2--3

The Astrophysical Journal (Impact Factor: 6.28). 12/2011; 743. DOI: 10.1088/0004-637X/743/1/87

ABSTRACT We present our results on the structure and activity of massive galaxies at z = 1-3 using one of the largest (166 with M sstarf >= 5 × 1010 M ☉) and most diverse samples of massive galaxies derived from the GOODS-NICMOS survey: (1) Sérsic fits to deep NIC3 F160W images indicate that the rest-frame optical structures of massive galaxies are very different at z = 2-3 compared to z ~ 0. Approximately 40% of massive galaxies are ultracompact (re

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