Finding structures in photometric redshift galaxy surveys: an extended friends-of-friends algorithm

  title={Finding structures in photometric redshift galaxy surveys: an extended friends-of-friends algorithm},
  author={Christine S. Botzler and Jan Snigula and Ralf Bender and Usm Muenchen and Max-Planck-Institut fuer extraterrestrische Physik},
  journal={Monthly Notices of the Royal Astronomical Society},
We present a modified version of the friends-of-friends (FOF) structure-finding algorithm, designed specifically to locate groups or clusters of galaxies in photometric redshift data sets. The main objective of this paper is to show that this extended friends-of-friends (hereafter EXT-FOF) algorithm yields results almost identical to the original FOF, if applied to a spectroscopic redshift data set, and a rather conservative catalogue of structures, in case of a data set with simulated… Expand

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