The search and investigation of the Large Groups of Quasars

  title={The search and investigation of the Large Groups of Quasars},
  author={Boris V. Komberg and Andrey V. Kravtsov and Vladimir N. Lukash Astro Space Center and Moscow and New Mexico State University},
  journal={arXiv: Astrophysics},
Recently, it was suggested that large concentrations or groups of quasars may trace sites of enhanced matter density at medium and high redshifts analogous to how galaxy clusters trace them in nearby space. We have checked existing quasar data for the presence of such groups. Large Quasar Groups (LQGs) were identified using a well-known cluster analysis technique. Our final list consists of 12 groups, including one reported previously. Most of the quasars in these groups come from deep… 

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