A New Empirical Model for the Structural Analysis of Early-Type Galaxies, and A Critical Review of the Nuker Model*

  title={A New Empirical Model for the Structural Analysis of Early-Type Galaxies, and A Critical Review of the Nuker Model*},
  author={Alister W. Graham and Peter Erwin and Ignacio Trujillo and A. Asensio Ramos},
  journal={The Astronomical Journal},
The Nuker law was designed to match the inner few (~3–10) arcseconds of predominantly nearby (30 Mpc) early-type galaxy light profiles; it was never intended to describe an entire profile. The Sersic model, on the other hand, was developed to fit the entire profile; however, because of the presence of partially depleted galaxy cores, the Sersic model cannot always describe the very inner region. We have therefore developed a new empirical model consisting of an inner power law, a transition… 
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