Mass determination of groups of galaxies: Effects of the cosmological constant

  title={Mass determination of groups of galaxies: Effects of the cosmological constant},
  author={S{\'e}bastien Peirani and J. A. Freitas Pacheco},
  journal={New Astronomy},
Abstract The spherical infall model first developed by Lemaiˆtre and Tolman was modified in order to include the effects of a dark energy term. The resulting velocity–distance relation was evaluated numerically. This equation, when fitted to actual data, permits the simultaneous evaluation of the central mass and of the Hubble parameter. Application of this relation to the Local Group, when the dark energy is modeled by a cosmological constant, yields a total mass for the M31-Milky Way pair of… Expand

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