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The Colour-Magnitude Relation of Early-Type Galaxies in the Hubble Deep Field

Tadayuki Kodama·Richard G. Bower·Eric F. Bell
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Abstract

We present the rest-frame colour-magnitude diagram for 35 early-type galaxies in the Hubble Deep Field with median redshift 0.9. Although with considerable scatter, a red sequence well-described by the passive evolution of an intrinsically old stellar population is observed. Comparison with the passively evolved colour-magnitude relation of the rich Coma cluster ($z=0.023$) indicates that around half of the early-type galaxies in the field at this redshift are as old as those in rich clusters.

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Tadayuki Kodama, Richard G. Bower, Eric F. Bell. 1998-10-08. The Colour-Magnitude Relation of Early-Type Galaxies in the Hubble Deep Field. https://doi.org/10.1023/a%3A1017520213745

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