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Photometric validation of a model independent procedure to extract galaxy clusters

E. Puddu·S. Andreon·G. Longo·V. Strazzullo·M. Paolillo·R. Gal
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Abstract

By means of CCD photometry in three bands (Gunn g, r, i) we investigate the existence of 12 candidate clusters extracted via a model independent peak finding algorithm (\cite{memsait}) from DPOSS data. The derived color-magnitude diagrams allow us to confirm the physical nature of 9 of the cluster candidates, and to estimate their photometric redshifts. Of the other candidates, one is a fortuitous detection of a true cluster at z~0.4, one is a false detection and the last is undecidable on the basis of the available data. The accuracy of the photometric redshifts is tested on an additional sample of 8 clusters with known spectroscopic redshifts. Photometric redshifts turn out to be accurate within z~0.01 (interquartile range).

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E. Puddu, S. Andreon, G. Longo, V. Strazzullo, M. Paolillo, R. Gal. 2001-10-15. Photometric validation of a model independent procedure to extract galaxy clusters. https://doi.org/10.1051/0004-6361%3A20011316

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