1 research outputs found
Distortion of Globular Clusters by Galactic Bulges
One of the external fields that influences the population of globular
clusters is that due to galactic bulges. In extreme situations, perigalactic
distances pc, globular clusters could suffer total disruption in
a single passage. A more common scenario is that for cluster orbits with pc. We investigate the effects of tidal forces from a bulge on the
shape of globular clusters for this type of encounters. We find distortions
characterized by ``twisting isophotes'' and consider the potential for
observability of this effect. In the Milky Way, a typical globular cluster must
pass within several hundred pc of the center to experience substantial
distortion, and it is possible that this has happened recently to one or two
present day clusters. We estimate that this distortion could be observed even
for globulars in dense fields toward the bulge. In more extreme environments
such as giant ellipticals or merger products with newly formed globulars, this
effect could be more common, extending out to orbits that pass within 1 kpc of
the bulge center. This would lead to a substantial shift in the eccentricity
distribution of globulars in those galaxies.Comment: 12 pages, 8 figure