Astrophysics (index)

de Vaucouleurs' Profile

(de Vaucouleurs' Law, R To The 1/4 Law)
(relation between elliptical galaxy surface brightness and distance from center)

The de Vaucouleurs' Profile (or de Vaucouleurs' Law, or R To The 1/4 Law) is a relation between the Surface Brightness of a point on an Elliptical Galaxy and that point's distance from the Galaxy's center.

ln ΣR = ln Σ0 - k R1/4
  • R - radius, a distance from the center of the galaxy.
  • ΣR - surface brightness at that radius.
  • Σ0 - surface brightness at the center.
  • k - a constant.

This is an empirical relation and unfortunately it has limited use for determining other information, but is a relation that any theory of elliptical galaxies had best reproduce. I believe some models of Galaxy Mergers appear to produce galaxies with such a relation, consistent with the notion that elliptical galaxies are often the result of mergers.

Other such empirical relations regarding galaxy surface brightness have been devised.

(relation,galaxies,surface brightness)