Astronomy and Astrophysics – Astrophysics
Scientific paper
2001-09-26
Mon.Not.Roy.Astron.Soc. 330 (2002) 1
Astronomy and Astrophysics
Astrophysics
Accepted for publication in MNRAS - 18 pages
Scientific paper
10.1046/j.1365-8711.2002.04984.x
We present the results of a survey for Extremely Red Objects (EROs) in the fields of ten galaxy cluster lenses at z~0.2, combining high-resolution Hubble Space Telescope imaging with deep K-band imaging from UKIRT. We detect 60 EROs with R-K>=5.3, of which 26 have R-K>=6.0 in a total image plane survey area of 49arcmin^2 down to K=20.6. We use detailed models of the cluster lenses to quantify the lens amplification and thus correct the observed number counts and survey area for the effects of gravitational lensing. After making these corrections, we estimate surface densities at K<=21.6 of 2.5+/-0.4 and 1.2+/-0.3 arcmin^-2 for EROs with R-K>=5.3 and 6.0 respectively. These ERO number counts agree with previous shallower surveys at K<~19 and flatten significantly at magnitudes fainter than K~19-20. This flattening may be due to a transition from an ERO population dominated by evolved galaxies at z~1-2 (K<~19.5) to one dominated by dusty starburst galaxies at z>1 (K>~19.5). We also compare our results with various model predictions, including a model that attempts to explain EROs in terms of a single population of elliptical galaxies formed at high redshift. We find that a formation epoch of z_f~2.5 for this population matches the observed surface density of R-K>=5.3 EROs quite well, and the R-K>=6.0 sample less well. More sophisticated models, including semi-analytic prescriptions, under-predict the ERO surface density by approximately an order of magnitude, suggesting that these models produce insufficient stars and/or dust at high redshift.
Czoske Oliver
Ebeling Harald
Edge Alastair
Ivison Rob
Kneib Jean Paul
No associations
LandOfFree
A Hubble Space Telescope Lensing Survey of X-ray Luminous Galaxy Clusters: II. A Search for Gravitationally Lensed EROs does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with A Hubble Space Telescope Lensing Survey of X-ray Luminous Galaxy Clusters: II. A Search for Gravitationally Lensed EROs, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A Hubble Space Telescope Lensing Survey of X-ray Luminous Galaxy Clusters: II. A Search for Gravitationally Lensed EROs will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-634817