We describe the HST ACS Coma cluster Treasury survey, a deep twopassband imaging survey of one of the nearest rich clusters of galaxies, the Coma cluster (Abell 1656). The survey was designed to cover an area of 740 arcmin2 in regions of different density of both galaxies and intergalactic medium within the cluster. The ACS failure of January 27th 2007 leaves the survey 28% complete, with 21 ACS pointings (230 arcmin2) complete, and partial data for a further 4 pointings (44 arcmin2). Predicted survey depth for 10 detections for optimal photometry of point sources is g′ = 27.6 in the F475W filter, and IC=26.8 mag in F814 (AB magnitudes). Initial simulations with artificially injected point sources show 90% recovered at magnitude limits of g′ = 27.55 and IC = 26.65. For extended sources, the predicted 10 limits for a 1 arcsecond2 region are g′ = 25.8 mag arcsec−2 and IC = 25.0 mag arcsec−2. We highlight several motivating science goals of the survey, including study of the faint end of the cluster galaxy luminosity function, structural parameters of dwarf galaxies, stellar populations and their effect on colors and color gradients, evolution of morphological components in a dense environment, the nature of ultra compact dwarf galaxies, and globular cluster populations of cluster galaxies of a range of luminosities and types. This survey will also provide a local rich cluster benchmark for various well known global scaling relations and explore new relations pertaining to the nuclear properties of galaxies.

Publication Date



Also archived in: arXiv:0801.3745 v1 Jan 24 2008Note: imported from RIT’s Digital Media Library running on DSpace to RIT Scholar Works in February 2014.

Document Type


Department, Program, or Center

School of Physics and Astronomy (COS)


RIT – Main Campus