Quantifying the coherent outflows of galaxies around voids in the SDSS DR7

  title={Quantifying the coherent outflows of galaxies around voids in the SDSS DR7},
  author={Santiago G. Patiri and Juan E. Betancort-Rijo and Francisco Prada},
  journal={Astronomy and Astrophysics},
We report the detection, with a high level of confidence, of coherent outflows around voids found in the seventh data release of the Sloan Digital Sky Survey (SDSS DR7). In particular, we developed a robust �| cos θ|� statistical test to quantify the strength of redshiftspace distortions (RSD) associated with extended coherent velocity fields. We consistently find that the vector that joins void centers with galaxies that lie in shells around them is more likely to be perpendicular to the line… 

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