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Extremely Red Galaxies

Paola Andreani·Andrea Cimatti·Huub Roettgering·Remo Tilanus
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Abstract

Preliminary results of a project aiming at unveiling the nature of the extremely red galaxies (ERGs) (objects with colours R-K>6 and I-K>5) found in deep optical-NIR surveys are presented. Very little is known about these objects, the critical issue being whether they are old ellipticals at z>1 or distant star-forming galaxies strongly reddened by dust extinction. We expect to shed light onto the unknown nature of these galaxies by completing our three-step project: (1) the construction of two very deep optical/NIR surveys to select ERGs, (2) subsequent VLT/NIR spectroscopy; (3) observations in the sub-mm region with SCUBA at the JCMT and with MPIfRbolo at the IRAM 30m antenna.

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Paola Andreani, Andrea Cimatti, Huub Roettgering, Remo Tilanus. 1999-03-09. Extremely Red Galaxies. https://arxiv.org/abs/astro-ph/9903121

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