A Group of Red, L[CLC]y[/CLC]α-emitting, High-Redshift Galaxies

Abstract
We have discovered two new high-redshift (z = 2.38) galaxies near the previously known z = 2.38 galaxy 2139-4434B1 (Francis et al.). All three galaxies are strong Lyα emitters and have much redder continuum colors (I - K ~ 5) than other optically selected high-redshift galaxies. We hypothesize that these three galaxies are QSO II's, radio-quiet counterparts of high-redshift radio galaxies containing concealed QSO nuclei. The red colors are modeled most easily by an old (>0.5 Gyr), massive (>1011 M) stellar population. If true, this implies that at least one galaxy cluster of mass 3 × 1011 M had collapsed before redshift 5.
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