The Outer Halos of Elliptical Galaxies

  title={The Outer Halos of Elliptical Galaxies},
  author={Ortwin Gerhard},
  journal={arXiv: Astrophysics of Galaxies},
  • O. Gerhard
  • Published 17 September 2010
  • Physics
  • arXiv: Astrophysics of Galaxies
Recent progress is summarized on the determination of the density distributions of stars and dark matter, stellar kinematics,and stellar population properties in the extended, low-surface brightness halo regions of elliptical galaxies. With integral field absorption spectroscopy and with planetary nebulae as tracers,velocity dispersion and rotation profiles have been followed to ~ 4 and ~ 5–8 effective radii, respectively, and in M87 to the outer edge at ~ 150 kpc. The results are generally… 
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