Fluctuations in the IRAS 1.2 Jy Catalogue

Martin Kerscher; Jens Schmalzing; Thomas Buchert; Herbert Wagner

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arXiv · astro-ph/9704028

Fluctuations in the IRAS 1.2 Jy Catalogue

Martin Kerscher·Jens Schmalzing·Thomas Buchert·Herbert Wagner

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Abstract

An analysis of the IRAS 1.2 Jy redshift catalogue with emphasis on the separate examination of northern and southern parts (in galactic coordinates) is performed using a complete set of morphological descriptors (Minkowski functionals), nearest neighbour distributions and the variance of the galaxy counts. We find large fluctuations in the clustering properties as seen in a large difference between the northern and southern parts of the catalogue on scales of 100Mpc/h. These fluctuations remain discernible even on the scale of 200Mpc/h. We also identify sparse sampling as a major source of ``apparent homogenization''. Tests on observational selection effects concerning luminosity, colour and redshift-space distortion support the significance of these large-scale fluctuations.

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Martin Kerscher, Jens Schmalzing, Thomas Buchert, Herbert Wagner. 1998-04-14. Fluctuations in the IRAS 1.2 Jy Catalogue. https://arxiv.org/abs/astro-ph/9704028

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