EROs in the EIS fields
I. The AXAF (Chandra) deep field *
M. Scodeggio ** and
Received 28 May 1999 / Accepted 14 April 2000
The publicly available EIS-DEEP optical-NIR data for the AXAF (Chandra) Deep Field have been used to construct samples of Extremely Red Objects (EROs) using various single-band and multi-band color criteria. In this work we define as EROs objects with colors consistent with passively evolving elliptical galaxies at 1. The EROs surface densities we derive are intermediate between previous published values, emphasizing again the need for larger survey areas to constrain the effects of possible large-scale structure. Although various single-color selected samples can be derived, the EROs sample selected using jointly is likely to contain the highest fraction of passively evolving luminous field elliptical galaxies at 1, or conversely, the lowest fraction of lower redshift interlopers. The surface density of this multi-band selected EROs sample is consistent with the conclusion that little or no field elliptical volume density evolution has occurred in the redshift range 0 1.5. However, extensive spectroscopic followup is necessary to confirm this conclusion.
Key words: galaxies: elliptical and lenticular, cD galaxies: evolution galaxies: formation cosmology: observations
* Based on observations collected at the European Southern Observatory, La Silla, Chile; ESO programs No. 61.A-9005 and 162.O-0917
Send offprint requests to: Marco Scodeggio
This article contains no SIMBAD objects.
© European Southern Observatory (ESO) 2000
Online publication: July 13, 2000