Advanced search
Start date

The Northern Sky Optical Cluster Survey III: A Cluster Catalog Covering Pi Steradians

Grant number: 08/10019-2
Support type:Regular Research Grants - Publications - Scientific article
Duration: December 01, 2008 - May 31, 2009
Field of knowledge:Physical Sciences and Mathematics - Astronomy - Extragalactic Astrophysics
Principal Investigator:Paulo Afranio Augusto Lopes
Grantee:Paulo Afranio Augusto Lopes
Home Institution: Instituto de Pesquisa e Desenvolvimento (IP&D). Universidade do Vale do Paraíba (UNIVAP). São José dos Campos , SP, Brazil


We present the complete galaxy cluster catalog from the Northern Sky Optical ClusterSurvey, a new, objectively defined catalog of candidate galaxy clusters at z << 0.25drawn from the Digitized Second Palomar Observatory Sky Survey (DPOSS). The datapresented here cover the Southern Galactic Cap, as well as the less-well calibrated regionsof the Northern Galactic Cap. In addition, due to improvements in our clusterfinder and measurement methods, we provide an updated catalog for the well-calibratedNorthern Galactic Cap region previously published in Paper II. The complete surveycovers 11,411 square degrees, with over 15,000 candidate clusters. We discuss improvedphotometric redshifts, richnesses and optical luminosities which are provided for eachcluster. A variety of substructure measures are computed for a subset of over 11,000clusters. We also discuss the derivation of dynamical radii r200 and its relation to clusterrichness. A number of consistency checks between the three areas of the survey are alsopresented, demonstrating the homogeneity of the catalog over disjoint sky areas. Weperform extensive comparisons to existing optically and X-ray selected cluster catalogs,and derive new X-ray luminosities and temperatures for a subset of our clusters. Wefind that the optical and X-ray luminosities are well correlated, even using relativelyshallow ROSAT All Sky Survey and DPOSS data. This survey provides a good comparisonsample to the MaxBCG catalog based on Sloan Digital Sky Survey Data, andcomplements that survey at low redshifts 0.07 < z < 0.1 (AU)