Evidence for an Outer Disk in the Prototype “Compact Elliptical” Galaxy M32

  title={Evidence for an Outer Disk in the Prototype “Compact Elliptical” Galaxy M32},
  author={Alister W. Graham},
  journal={The Astrophysical Journal},
  • A. Graham
  • Published 15 February 2002
  • Physics
  • The Astrophysical Journal
M32 is the prototype for the relatively rare class of galaxies referred to as compact ellipticals. It has been suggested that M32 may be a tidally disturbed r1/4 elliptical galaxy or the remnant bulge of a disk-stripped early-type spiral galaxy. This Letter reveals that the surface brightness profile, the velocity dispersion measurements, and the estimated supermassive black hole mass in M32 are inconsistent with the galaxy having, and probably ever having had, an r1/4 light profile. Instead… 

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