The dynamical evolution of a single globular cluster and also of the entire
Galactic globular cluster system has been studied theoretically in detail. In
particular, simulations show how the 'lost' stars are distributed in tidal
tails emerging from the clusters. We investigate the distribution of Galactic
globular cluster stars on the sky to identify such features like tidal tails.
The Sloan Digital Sky Survey provides consistent photometry of a large part of
the sky to study the projected two dimensional structure of the 17 globular
clusters in its survey area. We use a color-magnitude weighted counting
algorithm to map (potential) cluster member stars on the sky. We recover the
already known tidal tails of Pal 5 and NGC 5466. For NGC 4147 we have found a
two arm morphology. Possible indications of tidal tails are also seen around
NGC 5053 and NGC 7078, supporting earlier suggestions. Moreover, we find
potential tails around NGC 5904 and Pal 14. Especially for the Palomar clusters
than Pal 5, deeper data are needed in order to confirm or to rule out the
existence of tails. For many of the remaining clusters in our sample we observe
a pronounced extratidal halo, which is particularly large for NGC 7006 and Pal
1. In some cases, the extratidal halos may be associated with the stream of the
Sagittarius dwarf spheroidal galaxy (e.g.,NGC 4147, NGC 5024, NGC 5053).Comment: Accepted by A&A, 24 pages, 24 figure