ar X iv : a st ro - p h / 04 05 57 4 v 1 2 8 M ay 2 00 4 Colour – detected clusters in the XMM Large Scale Structure Survey
نویسندگان
چکیده
We present first results on the use of a colour space filter for detecting galaxy clusters at cosmological redshifts in the XMM Large Scale Structure Survey. All clusters studied, but one, are successfully colour–detected in spite of their large redshift (0.3 < z < 1.0), X–ray selection and intrinsic low richness (R = 0 or below). We experimentally show that the cluster redshift can be derived, with good accuracy, from the colour of the red sequence, at 0.06 < z < 1 using a sample of about 160 clusters.
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