Astronomy and Astrophysics – Astrophysics
Scientific paper
2005-03-16
Astron.J. 127 (2004) 2482
Astronomy and Astrophysics
Astrophysics
33 pages in emulate ApJ format. 33 figures, of which 10 are large finding charts in jpeg format. Monolithic manuscript with fi
Scientific paper
10.1086/382722
We present a study of the color evolution of elliptical and S0 galaxies in six clusters of galaxies inside the redshift range 0.78 < z < 1.27. For each cluster, we used imaging from the Hubble Space Telescope to determine morphological types by both an automated technique and from visual inspection. We performed simulations to determine the accuracy of the automated classifications and found a success rate of ~75% at m(L*) or brighter magnitudes for most of our HST imaging data with the fraction of late--type galaxies identified as early--type galaxies to be ~10% at m(L*) to ~20% at m(L*)+2. From ground based optical and near-infrared imaging, we measured the zero-point and scatter in the color--magnitude relation of the early-type populations, which when combined with Stanford et al. (1998), yields a sample of cluster early--type galaxies that span a lookback time of 9 gigayears from the present. We see the colors of the early--type cluster members become bluer with increasing redshift. We fit a set of models to the change in the color as a function of redshift with the best fitting values ranging from a formation redshift of 3^+2_-1 to 5_-3. The large scatter in resulting formation epochs, which depends on the details of the models used, implies that we can conclude that the oldest stars in the elliptical galaxies appear to have formed at redshifts of z>3. We find possible evolution in the scatter of the colors, with some high redshift clusters showing scatter as small as the Coma cluster but others showing much larger scatter. Those clusters with a small scatter imply either a formation redshift of at least z ~ 3 or a smaller spread in the range of formation redshifts at lower redshifts, assuming a Gaussian distribution of star-formation around the mean epoch.
Dickinson Marc
Eisenhardt Peter
Holden Bradford P.
Stanford Spencer A.
No associations
LandOfFree
Evolution in the Color-Magnitude Relation of Early-Type Galaxies in Clusters of Galaxies at z~=1 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 Evolution in the Color-Magnitude Relation of Early-Type Galaxies in Clusters of Galaxies at z~=1, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Evolution in the Color-Magnitude Relation of Early-Type Galaxies in Clusters of Galaxies at z~=1 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-569573