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arXiv · astro-ph/0610910

Witnessing the formation of a brightest cluster galaxy at z>2

Abstract

We present deep observations taken with the HST Advanced Camera for Surveys of the central massive galaxy in a forming cluster at z=2.2. The galaxy hosting the powerful radio source MRC 1138-262 is associated with one of the most extensive merger systems known in the early universe. Our HST/ACS image shows many star-forming galaxies merging within a ~200 kpc region that emits both diffuse line emission and continuum in the rest-frame UV. Because this galaxy lives in an overdense environment, it represents a rare view of a brightest cluster galaxy in formation at z>2 which may serve as a testbed for predictions of massive cluster galaxy formation.

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Roderik A. Overzier, George K. Miley, Holland C. Ford. 2006-10-30. Witnessing the formation of a brightest cluster galaxy at z>2. https://doi.org/10.1016/j.newar.2006.11.021

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