De Vaucouleurs profile

The De Vaucouleurs profile (after Gérard-Henri de Vaucouleurs ) describes how the surface brightness of an elliptical galaxy or the bulge of a spiral galaxy changes with the distance from the center. In a simple form it can be written as: ${\displaystyle I}$ ${\displaystyle R}$

${\displaystyle I(R)=I_{e}\cdot \exp \left(-7,669\cdot \left[\left({\frac {R}{R_{e}}}\right)^{\frac {1}{4}}\,-1\right]\right)}$

Here the surface brightness is at the effective radius (i.e. at the radius within which half the luminosity is emitted). ${\displaystyle I_{e}}$ ${\displaystyle R_{e}}$

See also

• Sérsic profile , the generalized form

Individual evidence

1. ↑ Peter Schneider: Introduction to the extragalactic astronomy and cosmology . 2008, ISBN 978-3-540-30589-7 , pp. 55 .