Reconciling optical and X‐ray mass estimates: the case of the elliptical galaxy NGC 3379

  title={Reconciling optical and X‐ray mass estimates: the case of the elliptical galaxy NGC 3379},
  author={Silvia Pellegrini and Luca Ciotti},
  journal={Monthly Notices of the Royal Astronomical Society},
NGC 3379 is a well-studied nearby elliptical for which optical investigations have claimed a little dark matter content, or even no dark matter. Recently, its total mass profile M(r) has been derived by exploiting Chandra observations of its extended and X-ray emitting interstellar medium, based on the hypothesis of hydrostatic equilibrium for the hot gas. The resulting total mass within the effective radius R e has been claimed to be a few times larger than that found by optical studies. Here… 

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