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arXiv · 0712.1054

A Spectro-photometric Search for Galaxy Clusters in SDSS

Joo H. Yoon·Kevin Schawinski·Yun-Kyeong Sheen·Chang H. Ree·Sukyoung K. Yi
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Abstract

Recent large-scale galaxy spectroscopic surveys, such as the Sloan Digital Sky Survey (SDSS), enable us to execute a systematic, relatively-unbiased search for galaxy clusters. Such surveys make it possible to measure the 3-d distribution of galaxies but are hampered by the incompleteness problem due to fiber collisions. In this study we aim to develop a density measuring technique that alleviates the problem and derives densities more accurately by adding additional cluster member galaxies that follow optical color-magnitude relations for the given redshift. The new density measured with both spectroscopic and photometric data shows a good agreement with apparent information on cluster images and is supported by follow-up observations. By adopting this new method, a total of 924 $robust$ galaxy clusters are found from the SDSS DR5 database in the redshift range $0.05<z<0.1$, of which 212 are new. Local maximum-density galaxies successfully represent cluster centers. We provide the cluster catalogue including a number of cluster parameters.

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Joo H. Yoon, Kevin Schawinski, Yun-Kyeong Sheen, Chang H. Ree, Sukyoung K. Yi. 2008-03-17. A Spectro-photometric Search for Galaxy Clusters in SDSS. https://doi.org/10.1086/528958

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