The Observational Mass Function of Loose Galaxy Groups

  title={The Observational Mass Function of Loose Galaxy Groups},
  author={Marisa Girardi and Giuliano Giuricin},
  journal={The Astrophysical Journal},
  pages={45 - 56}
We analyze the three catalogs of nearby loose groups compiled by A. M. Garcia. She identified groups in a magnitude-limited redshift galaxy catalog, which covers about ~ of sky within cz = 5500 km s-1, using two methods, a percolation method and a hierarchical method. The free parameters of the group-selection algorithms were tuned to obtain similar catalogs of groups. The author also proposed a third catalog of groups, defined as a combination of the two. Each catalog contains almost 500… 

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