Previous abstract Next abstract
Session 106 - Clusters of Galaxies.
Display session, Saturday, January 10
Exhibit Hall,
There are many cosmological uses for rich clusters of galaxies. They provide useful constraints for theories of large-scale structure formation and evolution, and are valuable (possibly coeval) samples for studying galaxy evolution in dense environments. Studies of the cluster two-point correlation function and the power spectrum are important probes of large scale structure and the scenarios of its formation.
In view of the real need to generate well-defined, objective catalogs of galaxy clusters and groups, with well-understood selection criteria and completeness, we use DPOSS to create just such a catalog. The DPOSS has two main advantages over previous surveys: it goes a magnitude fainter than POSS-I, and allows us to use color information in selecting our candidates. The digitization and cataloging of objects allow us to detect clusters in an objective manner, unlike many previous surveys. Here we report on the preliminary results of this effort.
We utilize the (g-r)vs.(r-i) color-color diagram to select for early-type
galaxies, which are more likely to be cluster members. We then use the
adaptive kernel method to generate galaxy surface
density maps, from which cluster candidates are selected.
We not only successfully recover Abell clusters of
richness class 0 and higher but also find many new cluster candidates which
were apparently missed by Abell. In one DPOSS field, we find an average of
50 cluster candidates, or \sim1.5/sq. deg. These clusters are expected to
span the redshift range 0 The author(s) of this abstract have provided an email address for comments about the abstract: rrg@astro.caltech.edu
If you would like more information about this abstract, please follow the link to astro.caltech.edu/~sco/index.html. This link was provided by the author. When you follow it, you will leave the the Web space for this meeting; to return, you should use the Back button on your browser.