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Comparison between optical and X-ray cluster detection methods

S. Basilakos·M. Plionis·S. Georgakakis·I. Georgantopoulos·T. Gaga·V. Kolokotronis·G. C. Stewart
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Abstract

In this work we present combined optical and X-ray cluster detection methods in an area near the North Galactic Pole area, previously covered by the SDSS and 2dF optical surveys. The same area has been covered by shallow ($\sim 1.8$ deg$^{2}$) XMM-{\em Newton} observations. The optical cluster detection procedure is based on merging two independent selection methods - a smoothing+percolation technique, and a Matched Filter Algorithm. The X-ray cluster detection is based on a wavelet-based algorithm, incorporated in the SAS v.5.2 package. The final optical sample counts 9 candidate clusters with richness of more than 20 galaxies, corresponding roughly to APM richness class. Three, of our optically detected clusters are also detected in our X-ray survey.

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S. Basilakos, M. Plionis, S. Georgakakis, I. Georgantopoulos, T. Gaga, V. Kolokotronis, G. C. Stewart. 2003-10-09. Comparison between optical and X-ray cluster detection methods. https://arxiv.org/abs/astro-ph/0310249

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