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arXiv · astro-ph/0412257

Galaxy Groups in the SDSS-DR3

Manuel Merchan·Ariel Zandivarez
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Abstract

We present a new sample of galaxy groups identified in the Sloan Digital Sky Survey Data Release 3. Following previous works we use the well tested friend-of-friend algorithm developed by Huchra & Geller which take into account the number density variation due to the apparent magnitude limit of the galaxy catalog. To improve the identification we implement a procedure to avoid the artificial merging of small systems in high density regions and then apply an iterative method to recompute the group centers position. As a result we obtain a new catalog with 10864 galaxy groups with at least four members. The final group sample has a mean redshift of 0.1 and a median velocity dispersion of $230 km s^{-1}$.

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Manuel Merchan, Ariel Zandivarez. 2004-12-10. Galaxy Groups in the SDSS-DR3. https://doi.org/10.1086/427989

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