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Non-Gaussian morphology on large scales: Minkowski functionals of the REFLEX cluster catalogue

M. Kerscher·K. Mecke·P. Schuecker·H. B"ohringer·L. Guzzo·C. A. Collins·S. Schindler·S. De Grandi·R. Cruddace
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Abstract

In order to quantify higher-order correlations of the galaxy cluster distribution we use a complete family of additive measures which give scale-dependent morphological information. Minkowski functionals can be expressed analytically in terms of integrals of n-point correlation functions. They can be compared with measured Minkowski functionals of volume limited samples extracted from the REFLEX survey. We find significant non-Gaussian features in the large-scale spatial distribution of galaxy clusters. A Gauss-Poisson process can be excluded as a viable model for the distribution of galaxy clusters at the significance level of 95%.

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M. Kerscher, K. Mecke, P. Schuecker, H. B"ohringer, L. Guzzo, C. A. Collins, S. Schindler, S. De Grandi, R. Cruddace. 2001-07-27. Non-Gaussian morphology on large scales: Minkowski functionals of the REFLEX cluster catalogue. https://doi.org/10.1051/0004-6361%3A20011063

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