| Astrophysics (index) | about |
A Sérsic profile (or Sérsic model or Sérsic law) is an equation describing the relative surface brightness of a galaxy, stating that the log of the surface brightness falls off exponentially with distance from the center. The Sérsic index is the reciprocal of the exponent: i.e., if the exponent is 1/n, then n is the Sérsic index.
The Sérsic profile is a generalization of de Vaucouleurs' profile, which amounts to an Sérsic profile with an index of 4.