Motivation

The luminosity profile of disk galaxies luminosity follows a power law:
L~e^-r/h
where h is known as the "scale radius", the distance at which the density drops by 1/e.

More recently several authors have argued that at a certain radius, the scale length decreases, causing the profile to falls off much more steeply and effectively truncating the disk. Truncation radii have implications for: Interpreting observed galaxy rotation curves Formation and evolution of galactic warps Galaxy formation

(Pohlen et. al. 2002)

Since tidal tails have a strong dependence on the outer edges of the disk, studying tidal tails may give us information about the truncation radii of galaxies.