Detection of Evolved High-Redshift Galaxies in Deep NICMOS/VLT Impages

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Abstract
A substantial population of high-redshift, early-type galaxies is detected in very deep UBVRIJHK images. Four elliptical profile galaxies are identified in the redshift range 1<zz>1, Hm>0.2, suggesting that the major fraction of luminous Hubble sequence galaxies has evolved little since z~2. A highly complete photometric redshift distribution is constructed to H=25 (69 galaxies) that shows a broad spread of redshift, peaking at z~1.5, in reasonable agreement with some analyses of the Hubble Deep Field. Four "dropout" galaxies are detected at z≈3.8 and are compact in the IR, ~0.5 kpc h-1 at rest frame 3500 Å. No example of a blue IR-luminous elliptical galaxy is found, thus restricting the star formation epoch of elliptical galaxies to z≥5-10 for a standard initial mass function and modest extinction.