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A Group of Red, Ly-alpha Emitting, High Redshift Galaxies

Paul J. Francis·Bruce E. Woodgate·Anthony C. Danks
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Abstract

We have discovered two new high redshift (z=2.38) galaxies, near the previously known z=2.38 galaxy 2139-4434 B1 (Francis et al. 1996). All three galaxies are strong Ly-alpha emitters, and have much redder continuum colors (I-K about 5) than other optically-selected high redshift galaxies. We hypothesize that these three galaxies are QSO IIs; radio-quiet counterparts of high redshift radio galaxies, containing concealed QSO nuclei. The red colors are most easily modelled by an old (> 0.5 Gyr), massive (> 10E11 solar masses) stellar population. If true, this implies that at least one galaxy cluster of mass much greater than 3E11 solar masses had collapsed before redshift five.

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Paul J. Francis, Bruce E. Woodgate, Anthony C. Danks. 1997-03-27. A Group of Red, Ly-alpha Emitting, High Redshift Galaxies. https://doi.org/10.1086/310667

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